EFFECTS OF NUTRIENT MANAGEMENT STRATEGIES ON DRY MATTER AND GRAIN YIELD OF SOYBEAN AND DRY BEAN CROPPING SYSTEMS By Christian Raymond Terwillegar A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Crop and Soil Sciences – Master of Science 2021 ABSTRACT EFFECTS OF NUTRIENT MANAGEMENT STRATEGIES ON DRY MATTER AND GRAIN YIELD OF SOYBEAN AND DRY BEAN CROPPING SYSTEMS By Christian Raymond Terwillegar Increases in soybean (Glycine max L. Merr.) grain yield can be partially attributed to greater total dry matter (TDM) accumulation, but the relationship between dry matter (DM) accumulation and nutrient uptake across irrigated and non-irrigated conditions remains uncertain. Two multi-year trials investigated soybean dry matter and nutrient accumulation and partitioning, grain yield, and net economic return across multiple seeding rates and fertilizer strategies. The 148,000 seeds ha-1 rate significantly decreased yield in two of four site-years but no differences occurred at the remaining two site-years. Fertilizer strategies did not interact with seeding rate to influence grain yield across all site-years. When contemplating fertilizer application strategies, soil test values should still be the first factor considered. Greater grain yield potential from improved dry bean (Phaseolus vulgaris L.) varieties coupled with potential decreases in soil sulfur (S) supply may have affected the likelihood of a grain yield response to nitrogen (N) and sulfur application. Three multi-year trials were established in Michigan to evaluate nitrogen rate, sulfur rate, and sulfur source on dry bean growth and grain yield. Nitrogen and S application including S source did not improve grain yield or interact with variety to affect grain yield across site-years. Other factors including plant nodulation, biomass, and residual nitrate after harvest were affected by N or S treatments. Nutrient application, especially N, may still be required but in nominal quantities to account for the variable June planting conditions of this shorter-season cropping system. Sulfur applications may be better suited for more N-responsive crops within the dry bean cropping rotation. Copyright by CHRISTIAN RAYMOND TERWILLEGAR 2021 Dedicated to my family, friends, and colleagues who extended their love, assistance, and advice along the way. iv ACKNOWLEDGEMENTS My involvement in the soil fertility and nutrient management program at Michigan State University has been a worthwhile experience. I would like to thank my advisor Dr. Kurt Steinke for providing me with this opportunity to expand my knowledge in field research and soil fertility. Your guidance and assistance have shaped me for my future endeavors. I would also like to thank my committee members Dr. Martin Chilvers and Dr. Zach Hayden for their advice and guidance with my research. Thank you Andrew Chomas for your mentoring and assistance as the soil fertility research technician. Your input and expertise within field research and life will not be forgotten. Thank you to the MSU Farm staff and Mike Particka, John Calogero, Paul Horny, and Dennis Fleischmann for your coordination and support of field projects. In addition, I would like to thank Dry Bean Specialist Scott Bales for facilitating dry bean planting and harvest. Thank you to the previous and current graduate students Taylor Purucker, Seth Purucker, Sarah MacDonald, Lacie Mates, and Dr. Jeff Rutan for field help and friendships. I would like to thank the Terwillegar and Fisher families for their unbounded encouragement, love, and support. Lastly, I would like to thank Justine Fisher for your absolute love, patience, and encouragement throughout my master’s experience. I hope I may also offer the same support and guidance during your master’s journey. v TABLE OF CONTENTS LIST OF TABLES ....................................................................................................................... viii CHAPTER 1 LITERATURE REVIEW ................................................................................................................1 Soybean ................................................................................................................................1 Global and Domestic Soybean Production ..............................................................1 Seeding Rate and Plant Density ...............................................................................2 Nutrient Uptake, Partitioning, and Remobilization .................................................3 Nitrogen Uptake: ..........................................................................................3 Nitrogen Partitioning: ..................................................................................3 Nitrogen Removal: .......................................................................................4 Phosphorus Uptake: .....................................................................................4 Phosphorus Partitioning: ..............................................................................5 Phosphorus Removal: ..................................................................................5 Potassium Uptake: .......................................................................................5 Potassium Partitioning: ................................................................................6 Potassium Removal:.....................................................................................6 Sulfur Uptake: ..............................................................................................6 Sulfur Partitioning:.......................................................................................7 Sulfur Removal: ...........................................................................................7 Zinc Uptake:.................................................................................................7 Zinc Partitioning: .........................................................................................8 Zinc Removal: ..............................................................................................8 Dry Matter Accumulation, Partitioning, and Remobilization ..................................8 Nutrient Application ................................................................................................9 Nitrogen: ......................................................................................................9 Phosphorus: ................................................................................................10 Potassium: ..................................................................................................11 Sulfur: ........................................................................................................12 Zinc: ...........................................................................................................13 Dry Bean ............................................................................................................................13 Global and Domestic Dry Bean Production...........................................................13 Nitrogen .................................................................................................................14 Sulfur......................................................................................................................18 LITERATURE CITED ......................................................................................................22 CHAPTER 2 SOYBEAN SEEDING RATE AND NUTRIENT MANAGEMENT STRATEGIES IMPACT ON PLANT GROWTH AND GRAIN YIELD UNDER IRRIGATED AND NON-IRRIGATED SYSTEMS .....................................................................................................................................35 Abstract ..............................................................................................................................35 Introduction ........................................................................................................................36 vi Materials and Methods .......................................................................................................40 Results and Discussion ......................................................................................................43 Environmental Conditions .....................................................................................43 Dry Matter Accumulation and Partitioning ...........................................................43 Nutrient Accumulation...........................................................................................48 Grain Yield.............................................................................................................52 Economic Analysis ................................................................................................55 Conclusions ........................................................................................................................56 Acknowledgements ............................................................................................................57 APPENDICES ...................................................................................................................58 APPENDIX A: CHAPTER 2 TABLES ...............................................................59 APPENDIX B: CHAPTER 2 DATA COLLECTED BUT NOT INCLUDED IN PUBLICATION ....................................................................................................70 LITERATURE CITED ......................................................................................................99 CHAPTER 3 NITROGEN AND SULFUR RESPONSES OF DRY BEAN IN MICHIGAN ..........................107 Abstract ............................................................................................................................107 Introduction ......................................................................................................................107 Materials and Methods .....................................................................................................111 Location and Site Description ..............................................................................111 Experimental Design and Procedures for N rate..................................................112 Experimental Design and Procedures for S rate ..................................................113 Experimental Design and Procedures for S Source .............................................114 Statistical Analyses ..............................................................................................115 Results and Discussion ....................................................................................................116 Environmental Conditions ...................................................................................116 Dry Bean Response to Nitrogen Rate ..................................................................116 Dry Bean Response to Sulfur Rate and Source ...................................................121 Implications for Dry Bean Growers .................................................................................123 Acknowledgements ..........................................................................................................124 APPENDICES .................................................................................................................126 APPENDIX A: CHAPTER 3 TABLES .............................................................127 APPENDIX B: CHAPTER 3 DATA COLLECTED BUT NOT INCLUDED IN PUBLICATION ..................................................................................................136 LITERATURE CITED ....................................................................................................137 vii LIST OF TABLES Table 2.01. Soil chemical properties and mean nutrient concentrations (0 to 20-cm depth) for irrigated and non-irrigated sites, Lansing, MI, 2019-2020 ............................................................59 Table 2.02. Monthlya, 30-yr averageb cumulative precipitation and air temperature, and supplemental irrigationc for the soybean-growing season (May-September), Lansing, MI, 2019- 2020................................................................................................................................................60 Table 2.03. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and R8 aboveground dry matter accumulation, Lansing, MI, 2019 ............61 Table 2.04. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and R8 aboveground dry matter accumulation, Lansing, MI, 2020 ............62 Table 2.05. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 aboveground nutrient accumulation, Lansing, MI, 2019 .........................................................63 Table 2.06. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 aboveground nutrient accumulation, Lansing, MI, 2020 .........................................................64 Table 2.07. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R8 aboveground nutrient accumulation, Lansing, MI, 2019. ........................................................65 Table 2.08. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R8 aboveground nutrient accumulation, Lansing, MI, 2020 .........................................................66 Table 2.09 Soybean grain yield as affected by seeding rate and fertilizer application for irrigated and non-irrigated sites, Lansing, MI, 2019-2020 ...........................................................................67 Table 2.10. Soybean seeding rate and fertilizer application effects on economic return for irrigated and non-irrigated sites, Lansing, MI, 2019-2020. ...........................................................68 Table 2.11. Break even soybean yield required to cover the partial budget costs as influenced by fertilizer application, Lansing, MI, 2019-2020 ..............................................................................69 Table 2.12. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and >R5-R8 percent of total aboveground dry matter accumulation, Lansing, MI, 2019 ..........................................................................................................................70 Table 2.13. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and >R5-R8 percent of total aboveground dry matter accumulation, Lansing, MI, 2020 ..........................................................................................................................71 viii Table 2.14. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 dry matter partitioning, Lansing, MI, 2019 ..............................................................................72 Table 2.15. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 dry matter partitioning, Lansing, MI, 2020 ..............................................................................73 Table 2.16. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R2 dry matter partitioning, Lansing, MI, 2019. .............................................................................74 Table 2.17. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R2 dry matter partitioning, Lansing, MI, 2020 ..............................................................................75 Table 2.18. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R5 dry matter partitioning, Lansing, MI, 2019 ..............................................................................76 Table 2.19. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R5 dry matter partitioning, Lansing, MI, 2020 ..............................................................................77 Table 2.20. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated R8 aboveground dry matter partitioning, Lansing, MI, 2019 .........................................78 Table 2.21. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated R8 aboveground dry matter partitioning, Lansing, MI, 2020 .........................................79 Table 2.22. Percentage of irrigated and non-irrigated season-long soybean nutrient accumulation at V4 as affected by seeding rate and fertilizer, Lansing, MI, 2019 ..............................................80 Table 2.23. Percentage of irrigated and non-irrigated season-long soybean nutrient accumulation at V4 as affected by seeding rate and fertilizer, Lansing, MI, 2020 ..............................................81 Table 2.24. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2019 .............................82 Table 2.25. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2020 .............................83 Table 2.26. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2019.................84 Table 2.27. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2020.................85 Table 2.28. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2019 ..................................................86 ix Table 2.29. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2020 ..................................................87 Table 2.30. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2019 .....................................88 Table 2.31. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2020 .....................................89 Table 2.32. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the pods, Lansing, MI, 2019 ....................................................90 Table 2.33. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the pods, Lansing, MI, 2020 ....................................................91 Table 2.34. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the grain, Lansing, MI, 2019 ...................................................92 Table 2.35. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the grain, Lansing, MI, 2020 ...................................................93 Table 2.36. Irrigated and non-irrigated soybean grain nutrient concentration at physiological maturity (R8) as affected by seeding rate and fertilizer application, Lansing, MI, 2019 ..............94 Table 2.37. Irrigated and non-irrigated soybean grain nutrient concentration at physiological maturity (R8) as affected by seeding rate and fertilizer application, Lansing, MI, 2020 ..............95 Table 2.38. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated nodule count, stem diameter, and pod count, Lansing, MI, 2019 ...................................96 Table 2.39. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated nodule count, stem diameter, and pod count, Lansing, MI, 2020 ...................................97 Table 2.40. Irrigated white mold incidence, white mold severity, and lodging as influenced by soybean seeding rate and fertilizer application, Lansing, MI, 2020 ..............................................98 Table 3.01. Soil chemical properties, mean P, K, and S concentrations (0-8 inches), and nitrate N content (0-1 ft), Richville, MI, 2019-2020 ..................................................................................127 Table 3.02 Monthlya and 30-yr averageb cumulative precipitation and air temperature for the dry bean-growing season (June-September), Richville, MI, 2019-2020 ...........................................128 Table 3.03. Influence of dry bean variety and N rate on tissue N concentration, nodule count, and plant height, Richville, MI, 2019-2020 ........................................................................................129 x Table 3.04. Influence of dry bean variety and N rate on R5 aboveground dry matter accumulation, white mold infection, and post-harvest residual NO3 N (0-1 ft), Richville, MI, 2019-2020 ....................................................................................................................................130 Table 3.05. Influence of dry bean variety and N rate on grain yield and economic return, Richville, MI, 2019-2020 .............................................................................................................131 Table 3.06. Impact of dry bean variety and S rate on grain yield and economic return, Richville, MI, 2019-2020 .............................................................................................................................132 Table 3.07. Influence of dry bean variety and S source on grain yield and economic return, Richville, MI, 2019-2020 .............................................................................................................133 Table 3.08. Dry bean variety and S rate effects on tissue S concentration and nodule number, Richville, MI, 2019-2020 .............................................................................................................134 Table 3.09. Dry bean variety and S source effects on tissue S concentration and nodule number, Richville, MI, 2019-2020 .............................................................................................................135 Table 3.10. Dry bean variety and N rate effects on V2 and R8 plant stand, Richville, MI, 2019- 2020..............................................................................................................................................136 xi CHAPTER 1 LITERATURE REVIEW Soybean Global and Domestic Soybean Production Globally soybean is currently a leading source of protein and oil for human food, animal feed, and industrial products (Wilson, 2008). Soybean meal produced in the crushing and oil extraction process accounts for the 65% of protein feed worldwide (Balboa et al., 2018). In 2017, the United States was the second largest exporter producing approximately 33% of world soybean production and exporting more than 59 million metric tons (USDA-FAS, 2017). In conjunction with the United States, Brazil, Argentina, China, India, Paraguay, and Canada produced approximately 94% of the world’s soybeans in 2017 (USDA-FAS, 2017). Soybean was first introduced within the United States as a forage crop in 1765 by Samuel Bowen (Hymowitz, 1990). However, it was until after World War II when the manufacturing of oil, meal, and food products from soybean increased the demand for a larger grain production market (Morse et al., 1950). During this same period, the United States surpassed China and later countries of the Orient in soybean production. (Hymowitz and Shurtleff, 2005). Between 1924 and 2018, average grain yield within the United States increased 324%. These on-farm yield gains are partially contributed to the adoption of new cultivars, improved agronomical practices, interactions between new cultivars and improved agronomical practices, and increased atmospheric CO2 levels (Long et al., 2006; Ziska and Bunce, 2007; Rowntree et al., 2013; Rowntree et al., 2014; Specht et al., 2014). 1 Seeding Rate and Plant Density Producers in the U.S. are forced to rethink optimum seeding rates for maximum yield and economic return due to the high cost of soybean seed (Chen and Wiatrak, 2011). Lee et al. (2008) reported seeding rates may be reduced below current recommendations (i.e., 300,000 to 516,000 seeds ha-1) without sacrificing yield. Elgi (1988b) found plant densities may be higher than those required to achieve 95% insolation interception at the growth stage R5 to maximize yields of indeterminate varieties. Harder et al. (2007) observed increasing seeding rate from approximately 300,000 plants ha-1 to 445,000 plants ha-1 did not result in quicker canopy closer, reduced weed emergence, or greater soybean yield and gross margins. In New York, a low seeding rate of 358,000 seeds ha-1 yielded similarly with the recommended 469,000 seeds ha-1 rate by producing additional side branches, vegetative biomass, pods, and seeds per plant (Cox et al., 2010). Koger (2009) also found low final plant populations produce optimum yields by compensating and increasing the number of fruiting branches, pods, and seeds per plant. However, high seeding rates provide protection against in-season stresses such as inadequate seedling emergence due to poor seed quality or unsuitable planting conditions but also increase the risk for white mold (Lee et al., 2008; Carpenter, 2020). When moisture is non-limiting, plant spacing has no effect on soybean yield (Alessi and Power, 1982; Board 2000). However, under extreme drought situations increased plant competition may reduce late-season water availability and ultimately yield due to increased early-season water use compared to decreased inter-plant competition (Alessi and Power, 1982). 2 Nutrient Uptake, Partitioning and Remobilization Nitrogen Uptake: Gaspar et al. (2017a) termed the first 20 day after emergence as a lag phase for N uptake due to N uptake rates < 1 kg ha-1 d-1. However, N uptake rates at 30 days after emergence (V4) is greater for high yield levels (5500 kg ha-1) compared to average (4500 kg ha- 1 ), and low yield levels (3500 kg ha-1) (Gaspar et al., 2017a). Total season-long N uptake by R1 for low, average, and high yield levels were reported at 14, 13, and 12%, respectively by Gaspar et al. (2017a). Previous research observed peak N uptake at R4 (Bender et al., 2017; Gaspar et al., 2017a). Bender et al (2015) found N uptake is evenly distributed between vegetative and seed-filling growth phases but Gaspar et al. (2017a) determined higher yield levels rely more heavily on N uptake from the soil after R5.5 than average and low yield levels. Moreover, Gaspar et al. (2017a) found total N uptake is greater for high yield levels compared to average and low yield levels, which is contributed from a shorter duration in the lag phase of early season N uptake, a higher peak N uptake rate, an extended peak uptake period, and greater late-season uptake amounts and rates. Nitrogen Partitioning: Past reports have indicated leaf tissue acts as a temporary N storage organ (Hanway and Weber, 1971a; Shibles and Sundberg, 1998; Sinclair, 1998). Gaspar et al. (2017a) suggest DM partitioning displays little influence on N partitioning. According to Gaspar et al. (2017a), N partitioned to leaves, seeds, stems, pods, and petioles across multiple yield levels at R5.5 was 43.7, 18.0, 16.2, 13.9, and 5.4%, respectively. Bender et al. (2015) reported over half of seed N accumulation occurs after the onset of seed-filling, indicating the importance of soil N resources to prevent yield losses. From what N is remobilized to the seed, 65% comes from leaf N contents and 32% comes from stem N contents (Bender et al., 2015). Compared to 3 older varieties, modern varieties can remobilize and uptake more N past R5.5 to meet seed N demands due to increased yield (Gaspar et al., 2017a). Nitrogen Removal: On a dry matter basis, Salvagiotti et al. (2008) observed a seed N concentration of 6.34%. At a yield level of 3480 kg ha-1, Bender et al. (2015) reported a nitrogen harvest index (NHI) of 73% while Hanway and Weber (1971) reported a NHI of 68% at a 2855 kg ha-1 yield level. Despite a significant interaction between environment and seed yield, Gaspar et al. (2017a) found NHI increased with seed yield for low (82.1%), average (83.3%) and high (84.1%) yield levels. Compared with the results from Salvagiotti et al. (2008), Gaspar et al. (2017a) observed current production realities incorporating modern soybean varieties and farm management practices combined with a greater NHI support a lower total N requirement across yield levels. Phosphorus Uptake: Compared to low (3500 kg ha-1) and average (4500 kg ha-1) yield levels, the lag phase of early season P uptake is shorter for high yield levels (5500 kg ha-1) (Gaspar et al., 2017b). In Wisconsin and Minnesota, early season P uptake acquired by R1 accounted for 15% (3.6 kg ha-1), 13% (3.9 kg ha-1), and 11% (4.1 kg ha-1) of total season-long P uptake for low, average, and high yield levels, respectively (Gaspar et al., 2017b). Phosphorus uptake reaches ~50% by R4 once reproductive growth is initiated (Hanaway and Weber, 1971; Bender et al., 2015). Bender et al. (2015) found peak P uptake rates were attained at R4 while Gaspar et al. (2017b) reported R3. Peak uptakes rates were reported as .34 kg P ha-1 d-1 by Hanway and Weber (1971), .40 kg P ha-1 d-1 by Bender et al. (2015), and .42, .48, and .56 kg P ha-1 d-1 for low, average, and high yield levels, respectively, by Gaspar et al. (2017b). Total P uptake for high (36.6 kg P ha-1), average (29.3 kg P ha-1), and low (24.4 kg P ha-1) yield levels was reported by 4 Gaspar et al. (2017b). Similar to N, P uptake is generally evenly distributed between vegetative and seed-filling growth phases (Bender et al., 2015; Gaspar et al., 2017b). Phosphorus Partitioning: Gaspar et al. (2017b) found P was partitioned into leaves (28.6%), stems (27.6%), pods (16.0%), seeds (15.4%), petioles (10.8%), and fallen leaves and petioles (<2%) at R5.5. Hanway and Weber (1971) reported P remobilization at 56% while Bender et al. (2015) reported P remobilization at 69%. New varieties and production practices compared to old varieties and production practices have resulted in greater remobilization and uptake of P past R5.5 (Gaspar et al., 2017b). Approximate seed P contributions between vegetative remobilization and continued uptake past R5.5 are approximately 50% (Bender et al., 2015 Gaspar et al., 2017b). Phosphorus Removal: Since the 1930’s, phosphorus harvest index (PHI) has increased from 68 to 80% in current soybean varieties (Borst and Thatcher, 1931). Seed PHI ranges from 72% to 82% on a DM basis (Hanway and Weber 1971; Bender et al., 2015; Gaspar et al., 2017b). According to Gaspar et al. (2017b), 23.8 kg P ha-1 would be removed with the seed at a yield of 4421 kg ha-1. Phosphorus HI is reported to vary due to environment but not yield (Gaspar et al. 2017b). Potassium Uptake: Instances of luxury K uptake have been observed when soil K supply was excessively high (Clover and Mallarino, 2013). Potassium uptake at R1 was observed at 26% (33.1 kg K ha−1), 22% (34.1 kg K ha−1), and 18% (34.4 kg K ha−1) of total season-long K at low (3000 kg ha-1), average (3500 kg ha-1), and high yield (5500 kg ha-1) levels, respectively (Gaspar et al. 2017b). Farmaha et al. (2012), however, found the K uptake rate at R1 to be 20 kg K ha-1. Potassium uptake nears completion by R5.5 for low yield levels whereas average and high yield 5 levels accrue 97% and 91% of total season-long K by R5.5, respectively (Gaspar et al., 2017b). If growing conditions after R5.5 are not suitable for average yields, luxury K accumulation will occur because a majority of total season-long K uptake is completed by R5.5 (Gaspar et al., 2017b). Peak uptake rates range from 1.5 kg K ha-1d-1 to 2.5 kg K ha-1 d-1 and occur shortly after R2 (Hanway and Weber, 1971; Gaspar et al., 2017b). Potassium Partitioning: Across multiple yield levels Gaspar et al. (2017b) found K was distributed equally to stems (31%), petioles (26%) and leaves (43%) at R1. Potassium remobilization at R5.5 ranges from 36% to 46.3% (Hanway and Weber, 1971; Bender et al., 2015; Gaspar et al., 2017b). Although continued K uptake past R5.5 is partitioned to the seed, K is also partitioned to the pod (Gaspar et al., 2017). However, seed K demands at multiple yield levels is mostly supplied by vegetative K remobilization (Hanway and Weber, 1971; Bender et al., 2015; Gaspar et al., 2017b). Potassium Removal: High and low STK levels have been shown to produce variable seed K concentrations (Parvej et al., 2016). Due to the relatively low amount of vegetative K that is remobilized to the seed, potassium harvest index (KHI) is also substantially low because a majority of K uptake remains in stems, petioles, leaves, and pods at maturity (Hanway and Weber, 1971; Bender et al., 2015; Gaspar et al., 2017b). Potassium HI ranges from 48.9% to 62% at maturity as reported by Hanway and Weber (1971), Bender et al. (2015), and Gaspar et al. (2017b). Due to > 50% of total K uptake potentially in the stover at harvest, the estimated amount of K removed in the stover may increase soil K depletion (Fixen et al., 2010). Sulfur Uptake: Gaspar et al (2018) found total S uptake is not dependent on environment or variety but is dependent on yield. Gaspar et al. (2018) reported a greater reliance on late season S 6 uptake for higher yields levels (5500 kg ha-1) than average (4500 kg ha-1) and low (3500 kg ha-1) yield levels. Peak S uptake occurs between R3 and R4 (Bender et al., 2015; Gaspar et al., 2018). Peak uptake rates vary between low (.26 kg S ha-1 d-1), average (.28 kg S ha-1 d-1), and high (.33 kg S ha-1 d-1) yield levels (Gaspar et al., 2018). After R5.5, Bender et al. (2015) and Gaspar et al. (2018) found S uptake ranged from 24.9% to 32.2% of season-long total S uptake. Sulfur Remobilization: When pooled across all yield levels at R5.5, 33.4, 28.8, 11.6, 12.9, and 10.2% of S was partitioned to the leaves, stems, seeds, pods, and petioles, respectively, while the remainder was lost to fallen leaves and petioles (Gaspar et al., 2018). On a relative basis, Bender et al. (2015) and Gasper et al. (2018) reported the total amount of vegetative S remobilized ranged from 40% to 50.1%. Seed S acquired during seed-fill from the soil is directly moved to the seed (Naeve and Shibles, 2005). The percentage of seed S demands met with continued uptake past R5.5 for low, average, and high yield levels is 49.9, 53.5, and 58% respectively (Gaspar et al., 2018). Sulfur Removal: Sulfur harvest index (SHI) ranges from approximately 61 to 69% according to Bender et al. (2015), Gaspar et al. (2018), and Sexton et al. (1998). Gaspar et al. (2018) reported 10.2 kg S ha-1, 12.3 kg S ha-1, and 15.1 kg S ha-1 being removed with the seed at low (3500 kg ha-1), average (4500 kg ha-1), and high yield levels (5500 kg ha-1). Greater S removal with the seed as yield increases (.0003 kg S kg grain-1) is mostly met by uptake from the soil after R5.5 (Gaspar et al., 2018). Zinc Uptake: At an average yield of 4421 kg ha-1, total Zn uptake is 22 kg ha-1 (Gaspar et al. (2018). Bender at al. (2015) found the peak S uptake rate of 3.57 to 3.99 g ha-1 d-1 occurs at R4. Approximately 53% of seed Zn is met through continued uptake past R5 (Gaspar et al. 2018), 7 and 335 g ha-1 is required to produce approximately 3500 and 9500 kg ha-1 of grain and total biomass, respectively (Bender et al, 2015). Zinc Remobilization: Zinc uptake prior to R1 or approximately 38 DAE is less than 17% of total season-long Zn uptake (Gasper et al., 2018). At R5.5, large portions of Zn (46%) is held in leaf tissue (Gaspar et al. 2018). On a per kg basis, Bender et al. (2015) reported grain Zn concentration at.40.2 mg. At an average yield level of 4421 kg ha-1, Gaspar et al. (2018) reported zinc harvest index (ZHI) at 68.7% while Bender et al. (2015) reported ZHI at 44%. Zinc Removal: At an average yield of 4421 kg ha-1, 16 kg Zn ha-1 is being removed with the seed at harvest (Gaspar et al. 2018). Due to such a small amount of Zn and other micronutrients being removed with the grain (< .18 kg ha-1), there is little or no need to fertilize for micronutrients as often you would fertilize with macronutrients (Gaspar et al., 2018). However, Bender et al. (2015) reported 195 g Zn ha-1 would be removed if the non-grain portion of the plant was not returned to the soil. Dry Matter Accumulation, Partitioning, and Removal Seed yields over the past century can partially be contributed to greater total plant DM through better management and improved plant genetics (Frederick et al., 1991; Rincker et al., 2014). In modern soybean varieties, each kilogram increase in yield translates to 1.45 kg increase in total dry matter accumulation (Gaspar et al., 2017a). Hanway and Weber (1971) found an average total dry matter accumulation of 9680 kg ha-1 for a yield level of 2983 kg ha-1 with a peak accumulation rate of 88 to 149 kg ha-1 d-1. However, Bender et al. (2015) reported an average DM accumulation of 9775 kg ha-1 for a yield of 3480 kg ha-1 with a peak accumulation rate of 162 kg ha-1 d-1 and Carpenter and Board (1997) found an accumulation rate of 60 kg ha-1 8 d-1 at R1 and a peak uptake rate of 180 kg ha-1 d-1 at a 3600 kg ha-1 yield level. Although yield increase as total DM increases, environmental factors affecting crop growth rate may also increase or decrease total DM accumulation (Muchow, 1985). Gaspar et al. (2017b) reported early season DM accumulation was mostly partitioned into leaf tissue until R1 when an increased amount of DM was transferred to stems, petioles and into pods at R3.5 and seeds at R4.5. Most DM is partitioned into the stems, followed by leaves, pods, petioles, seeds, and the rest as fallen leaves and petioles (Hanway and Weber, 1971; Bender et al., 2015; Gaspar et al., 2017a). Continued partitioning of DM to stems and pods occurs until R6.5 and remobilization of all vegetative DM at the peak DM accumulation is lower for high yield levels (5500 kg ha-1) than average (4500 kg ha-1) and low (3500 kg ha-1) yield levels (Gaspar et al., 2017a). This could theoretically lead to an extended duration of photosynthetic supply to the seed (Imsande, 1989). Harvest index (HI) differs for low (42.8%), average (44.2%), and high (45.2%) yield levels as reported by Gaspar et al. (2017a), suggesting greater total DM potentially does not always translate to greater grain yield. Nutrient Application Nitrogen: A growing soybean crop needs nitrogen from three different sources: N mineralization, synthetic N fertilizer, and biological N fixation (Barker and Sawyer, 2005; Salvagiotti et al., 2008). Biological N fixation can provide up to 50-60% of soybean’s total N requirement (Salvagiotti et al., 2008; Tamagno et al., 2017). Previous research reported N application reduces the number of nodules per plant and may sometimes reduce yield (Streeter and Wong, 1988; Hankinson et al., 2015). Although N application may reduce nodulation, certain forms of N such as nitrate are more sensitive to nodules than ammonium and urea 9 (Ralston and Imsande, 1983; Salsbury et al., 1986). Previous research has shown that N response in soybean is more likely under high yield conditions when N fixation and N mineralization are unable to provide sufficient N to meet crop demand (Salvagiotti et al., 2008). deMooy et al. (1973) found hot and dry conditions increases the likelihood of a grain yield increase to N application while adequate soil moisture and rainfall decreases the likelihood of a grain yield increase to N application. Slaton et al. (2013) observed N applied early in the growing season with P and K did not provide a yield benefit above what was responsive to P and K. However, in Minnesota, Schmitt reported N application increased grain yield at 9 of 13 site-years. Phosphorus: Phosphorus is important in crop production because it supports respiration, root growth, crop maturity, and drought tolerance (Bundy et al., 2005; Schlegel and Grant, 2006; Havlin et al., 2014). Under a short growing season and when soils are cool, starter P fertilizer has the potential to increase early-season vegetative growth and grain yield (Vitosh et al., 1995; Starling et al., 1998; Taylor et al., 2005; Elgi and Cornelius, 2009). However, under sufficient P soil concentrations, Purucker and Steinke (2020) did not contribute increased V4DM from a N, P, S, and Zn starter fertilizer to the P component. Sutradhar et al. (2017) found P applications at soil test phosphorus (STP) levels greater than 8 mg kg-1 increased grain yield. In addition, banding P with the planter in soils with low STP levels increases P uptake and grain yield compared to broadcasted P (Borges and Mallarino, 2000). Hairston et al. (1990) found deep injecting (15-cm depth) P fertilizer into soils with low STP levels increased the likelihood of a grain yield response in comparison to broadcasting P. Across all site-years, however, Hankinson et al. (2015) found P applied 2 inches below and 2 inches to the side of the seed at planting (i.e., 10 starter fertilizer) did not increase grain yield when STP levels were greater than 15 ppm. Bharati et al. (1986) reported lodging was significantly increased by P application. Potassium: Potassium is essential for crop growth and physiological functions, including the regulation of water and gas exchange, protein synthesis, enzyme activation, photosynthesis, and carbohydrate translocation (Marschner, 1998). Under K deficient conditions, plants may experience a reduction in plant growth, decreased drought resistance, weak stems, and greater susceptibility to disease (Sinclair, 1993, Mills and Jones, 1996). Potassium exists in most soils in the water-soluble form, readily exchangeable, and slowly exchangeable forms. However, most of the K in the soils is in the slowly exchangeable form while K uptake by the plant is mostly from the soluble and readily exchangeable forms (Hanway et al., 1985). In-season K applications can provide additional K during peak soybean uptake (Bender et al., 2015, Gaspar et al., 2017b) but yield responses depend on soil test K (STK) levels and environmental conditions (Haq and Mallarino, 2000; Nelson et al., 2005). Annual K fertilization rates that increase STK levels are desirable in low testing soils because they increase profits (Mallarino et al., 1991). Low soil test K levels may encourage K recycling in plant residues and extraction of K below the depth sampled and its later release on the surface soil (Mallarino et al., 1991). Moisture films around soil particles promotes diffusion and K uptake by the plant. Oliver and Barber (1966) estimated that 88 to 96% of K uptake reaches the roots by diffusion. Applied K should be placed where the soil will be moist and roots will be active if it’s to be utilized (Hanway et al., 1985). In a study conducted by Nelson et al. (2005), soybean yield was higher when K was soil applied compared to foliar applied. The vast majority of K uptake from K fertilization remained in the plant with no increase in yield or grain K (Oltmans and Mallarino, 2014). Potassium application increased 11 soybean yield at 16 site-years when the concentration of K in the was soil was at or less than 173 mg K kg-1 (Clover and Mallarino, 2013). However, Quinn and Steinke (2019) and Purucker and Steinke found the application of potassium thiosulfate and muriate of potash (MOP), respectively, did not increase soybean yield when soil test K concentrations were above critical across site-years. Additionally. Sale and Cambell (1986) suggest applications of K to correct late season deficiencies are of little use. Sulfur: Sulfur aids in amino acid synthesis increases resistance to cold temperatures and promotes soybean nodulation (Coleman, 1966). Results from Gutierrez Boem et al. (2007) suggest moderate S deficiency may reduce yield by affecting crop growth rate during the seed filling period due to sulfate mobility in the soil. Since the passage of The Clean Air Act of 1970, a significant reduction in atmospheric deposition of S-containing compounds on agriculture land has occurred (EPA, 2001). Kaiser et al. (2013) found soybean response to sulfur depends on the location, SOM, crop rotation, and S mineralization. Kaiser et al. (2013) also reported a response to S when SOM was less than 2%. In Michigan soil test S sufficiency ranges are not recommended due to SO4-S variability (Vitosh et al., 1995; Warncke et al., 2009). Tissue S and SOM are better predictors of a soybean S response rather than soil S (Hitsuda et al., 2008; Kaiser and Kim, 2013). Hitsuda et al. (2008) suggest S levels in the seed are a good indicator of the suflur fertility status of a field and may determine if sulfur fertilization is necessary before a subsequent soybean crop. Ham et al. 1975 found S fertilization does not increase total S percentage and S containing amino acids of the seed. In Ohio and Michigan under sufficient tissue S concentrations, Bluck et al. (2015) and Quinn and Steinke (2020), respectively, did not observe a grain yield response to S fertilization. 12 Zinc: Zinc deficiency can occur on a wide variety of soils with a high amount of silica and CaCO3 (Moraghan and Mascagni, 1991; Sutradhar et al., 2016). In Minnesota the application of Zn increased soybean trifoliate concentration but it did not increase soybean grain yield (Sutradhar et al., 2017). Soil tests do not predict a soybean grain yield response to Zn and there are no relationships between trifolliate Zn concentration and grain yield or to the soil test (Sutradhar et al., 2017). Research from Iowa showed that foliar appield Zinc increased Zn concentration in the trifoliate and seed but did not increase grain yield (Enderson et al., 2015). Across 18 sites in Iowa a fertilizer mixture that contained Zn sprayed at the V5 growth stage did not increase yield (Mallarino et al., 2001). However, Rose et al. (1981) found foliar applied Zn before flowering increased grain yield 13 to 208% at 75% of the locations. Dry Bean Global and Domestic Dry Bean Production Dry bean is a valuable legume crop and one of the leading sources of dietary protein worldwide. In 2019 the United States produced 1,165,416 tons of dry edible bean, of which Michigan accounted for 18% of total production (USDA-NASS, 2019). Michigan is the largest producer of black bean, navy bean and small red bean in the United States (USDA-NASS, 2020). Furthermore, Michigan plants additional market classes of dry bean including cranberry, dark red kidney, light red kidney, white kidney, pinto, and adzuki. 13 Nitrogen Compared with other legumes such as soybean, the ability of dry bean to fix N is relatively low, therefore mineral N and N fertilizer are essential to satisfy plant N demand (Fageria et al., 2014). The limited N fixation capacity of dry bean is thought to be the product of a low N requirement and presence of N assimilation traits favoring mineral N uptake rather than N fixation (George and Singleton, 1992). The contributions of symbiotic nitrogen fixation (SNF) and mineral N sources to total N accumulation are determined by the N requirement of dry bean and the mineral supply of N where if mineral N uptake is less than the N requirement, N fixation is potentially promoted (George and Singleton, 1992). However, environmental factors such as precipitation and temperature may impact the rate at which N mineralization and SNF occurs (Harper and Gibson, 1984; Andrews et al., 2005). For example, hot or cold weather and periods of soil water saturation can lead to the abortion or sloughing off of nodules, resulting in a greater demand for N uptake from other N sources (Liebman et al., 1995). In favorable environmental conditions, N availability may increase due to greater N mineralization from crop residues and organic matter, thus promoting higher yields (Franzen, 2017). Consequently, N fixation and mineral N uptake without the addition of N fertilizer may fail to support the N needs of a high yielding crop (Piha and Munns, 1987). Previous research has demonstrated dry bean may vary in response to N fertilizer addition across genotypes in part due to differences in N use efficiency (Fageria et al., 2013). Symbiotic N fixation begins once the colonization of the rhizosphere and the infection of the legume roots by rhizobia leads to nodule formation (Hardy et al., 1971). However, the capability of N fixation to support legume N supply may be influenced by environmental factors such as extreme pH, low soil temperature, drought, salinity, and soil deficiencies in P, K, and S 14 (Kumarasinghe et al., 1992; Faghire et al., 2011; Divito and Sandras, 2014). Due to the highly volatile nature of SNF in response to environmental conditions, N management in dry bean production poses a difficult challenge (Farid et al., 2015). Although most modern dry bean varieties were developed for high yield potential in N-rich soils, previous research has demonstrated high soil N levels negatively correlate with SNF (Salvagiotti et al., 2008). In a recent study evaluating 16 dry bean genotypes from different market classes under four different N treatments [not inoculated low N (27 lb N/acre) and high N (89 lb N/acre) and two rhizobia strains], Akter et al. (2018) verified a high dose of N fertilizer may suppress N fixation. Furthermore, Argraw and Akuma (2015) found a decrease in nodule number and weight with increased rates of N fertilizer in dry bean without inoculation. In addition to environmental factors and soil N level, nodulation can also be influenced by genotype (Fageria et al., 2013), where increased nodule number correlates with greater N fixation (Pereira et al., 1993). As a result, this discrepancy in nodulation (i.e., N fixing capabilities) across market classes and varieties may alter N management, especially in regions where dry bean producers grow multiple market classes. Dry bean needs 100 to 125 lb of N/acre for maximum yield in conjunction with N fixed by nodules on the plant (Hergert et al., 2013). To ensure high grain yield potential, Warncke et al. (2009) suggests applying 60 lb N/acre for when colored beans are grown under irrigation or if beans are planted in narrow rows (less than 23-inches), and 40 lb N/acre for all other beans under less intensive management systems. However, high rates of N applied pre-plant and incorporated has the potential to reduce plant stand due to saltation, but rainfall can mitigate risk for salt injury by reducing the concentration of N in the germination zone (Steinke and Bauer, 2017). In Wyoming, N rates of 0, 40, 80, 120, and 153 lb N/acre produced a curvilinear yield response in 15 one of three years and a linear response in the range of the rates used in two of three years (Blaylock., 1995). Moraghan et al. (1991) found the application of N fertilizer beyond 50 lb N/acre on navy bean did not significantly increase grain yield at one of four locations, where N fertilizer had either no impact or a decrease in grain yield at the remaining locations. Moreover, past research conducted by Edje et al. (1975) determined grain yield was greatest up to 71 lb N/acre across all site-years. Chekanai et al. (2018) observed greater pods per plant, number of seeds per pod, and grain yield when 36 lb N/acre was applied pre-plant compared to applying no N. Although previous research has shown the application of N at pre-plant leads to higher dry bean yields compared to applying N fertilizer after crop emergence (Kluthcouski et al., 2005), Sorrato et al. (2014) found grain yield was maximized at a V3 side-dressed N rate of 75 and 107 lb N/acre for a newly implemented no-tillage system and an established no-tillage system, respectively, in addition to 54 lb N/acre applied at pre-plant. However, without a split N application strategy, Eckert et al. (2011) determined 100 lb N/acre side-dressed at V3 did not significantly increase grain yield of three pinto bean cultivars. Previous research has documented greater initial plant growth of dry bean when there was a high availability of nutrients during the early stages of development (Kluthcouski et al., 2005). Additionally, Soratto et al. (2014) found the application of 54 lb N/acre before planting increased initial plant growth and decreased plant mortality during early vegetative stages and concluded N fertilizer was important for the acceptable establishment of dry bean. Karasu et al. (2011) reported increased doses of N ranging from 27 to 107 lb N/acre on dwarf dry bean cultivars resulted in greater plant height and more plant branches compared to applying no N, but there were no significant differences between N rates greater than 27 lb N/acre. Despite the potential benefit of increased grain yield and biomass production, the addition of N fertilizer may 16 also delay dry bean flowering and maturity (Reinprecht et al., 2020). In a study evaluating the application of 100 lb N/acre at V3, Eckert et al. (2011) observed a one-day delay in both the days to flowering and maturity. Furthermore, the over application of N fertilizer beyond a grain yield response may promote a microclimate within the bean canopy suitable for pathogen development, especially white mold (Phaseolus vulgaris L.). Outside of climatic conditions during canopy closure, which generally occurs during the flowering growth stages (R1-R3), N fertilizer may increase moisture within the canopy by stimulating foliage growth, thus decreasing air flow and lack of soil water evaporation (Miklas et al., 2013). This disease caused by the fungal pathogen Sclerotinia sclerotiorum, can limit yield potential and reduce seed and pod quality across many major bean producing regions (Singh and Schwartz, 2010). Apart from N fertilizer application, cultural practices such as row spacing, seeding rate, irrigation, and variety selection may also influence white mold infection. Nitrogen is the most frequently lacking and highest required nutrient in dry bean production (Fageria et al., 2014). To obtain maximum plant growth and yield, dry bean requires supplemental N fertilizer due to relatively poor N fixation. However, most plants are unable to utilize most of what N fertilizer is applied, thus excess N is subject to processes such as leaching, denitrification, volatilization, and erosion (Raun and Johnson, 1999; van Kessel and Hartley, 2000). In recent years, concerns over NO3-N pollution into ground water from leaching and runoff have practitioners interested in improving N management strategies. Biological nitrogen fixation is an economical and sustainable alternative for supplying N to dry bean (Thilakarathna and Raizada, 2018). By reducing N input, therefore simultaneously increasing symbiotic nitrogen fixation and nitrogen use efficiency, crop input cost and the negative impacts of unused nitrogen in the environment may be reduced. 17 Sulfur Sulfur (S) is required in high amounts because dry bean has a high protein content (Nascente et al., 2017). According to Sullieman et al. (2013), plants that acquire N by SNF have a greater S requirement than plants which only use soil N because S plays a significant role in N assimilation by N2 fixing bacteria. If S deficient, grain yield potential may decrease due to reduction in plant growth and formation of branches, flowers, and pods (Fageria et al., 2011). In a growth chamber under controlled environmental conditions, Ruiz et al. (2005) determined S deficient bean plants resulted in low NO3-N assimilation and biomass production. Furthermore, Pandurangan et al. (2015) observed S deficient bean plants reduced grain quality because storage proteins in developing seeds was altered. Due to the close linkage between S and N, failure to meet plant S demand may decrease N use efficiency and enhance the risk of N loss to the environment (Schnug and Haneklaus, 2005; Norton et al., 2013). Plants roots almost exclusively take up sulfur as SO4-S. The primary sources of readily available plant S are soil organic matter and atmospheric S deposition (Warncke et al., 2009). However, like N, environmental conditions can influence organic S mineralization and immobilization, the movement of S in the soil profile, and uptake of SO4-S by plants (Havlin et al., 2013). If soil temperature, pH, and moisture are unsuitable for microbial activity, the decomposition of organic materials from plant and animal residues may be reduced and soil S levels will decrease. In addition, the S content of decomposing material may also influence the rate at which decomposition occurs. When large amounts of OM residues are added to the soil, especially for those with a large C:S ratio (e.g., straw), adequate N and S availability is required to stimulate decomposition or otherwise a temporary N or S deficiency may occur in the subsequent crop (Havlin et al., 2013). In the soil SO4-S is transported to the roots by mass flow 18 and diffusion but because SO4-S in the soil solution is weakly adsorbed (Ishiguro & Makino, 2011), especially in sandy soils low in OM, it is readily subject to leaching. Historically, S application has not been recommended for dry bean production in Michigan because most soils should supply adequate S to meet crop S needs (Warncke et al., 2009). Studies in the past with S-responsive crops grown on potentially S-deficient sites in Michigan have generally not shown a beneficial response from S fertilizer additions (Warncke et al., 2009). However, a reduction in atmospheric S deposition and S containing inputs coupled with increased sulfur removal from high yielding crops has practitioners questioning the need for S fertilizer application (McGrath and Zhao, 1995; Sawyer & Barker, 2002; Warncke et al., 2009; Culman et al., 2020). Between 1980 and 2019, the average annual atmospheric deposition of S in southern Michigan has decreased by 85% (National Atmospheric Deposition Program, 2019). Because the exploitation of S accumulated in deeper soil layers by plant roots is limited during early growth, S fertilization at early stages may provide sufficient S supply throughout a crop’s growth cycle (Hitsuda et al., 2005). However, previous studies in soybean have shown that all potential S sources (i.e., OM, residual soil S, S-deposition, and fertilizer S), should be considered when determining S supply and availability (Kaiser and Kim, 2013; Norton et al., 2013; Quinn and Steinke, 2019). Although soils high in SO4-S may indicate the likelihood of a response to S application is low, it is difficult to diagnose soil S fertility through soil analysis because there is a large variation in the S content among different soil layers, therefore, a plant analysis is the best diagnostic tool for identifying S availability (Sawyer and Barker, 2002; Hitsuda et al., 2005; Culman et al., 2020). Culman et al. (2020) suggest the application of 10-20 lb S/acre should supply adequate S for grain crops if a S deficiency is expected. In Poland, Glowacka et al. (2019) found the application of 45 lb S/acre increased grain yield by 14.5% and improved grain quality, 19 thus concluding S fertilization should be included in the crop management practices of dry bean. In a systemic review of crop yield responses to S fertilization in Brazil, S application increased average grain yield 12% in 50% (n = 6) of dry bean studies (Pias et al., 2019). Under a sprinkler- irrigated and no-tillage system with S rates of 0, 9, 18, 36, and 54 lb S/acre, Nascente et al. (2017) observed 6 dry bean cultivars did not responded differently to S application. Moreover, other legumes such as soybean have generally produced inconsistent plant responses to supplemental S application. Bluck et al. (2015) did not observe a grain yield increase in response to S application under conditions with sufficient S tissue concentrations across 16 site-years. Quinn and Steinke (2019) did not significantly increase soybean grain yield across three site- years when potassium thiosulfate was surface banded at R1. Sulfur fertilizers contain either SO4-S, elemental S, or a mixture of (SO4-S + elemental S). When applied directly before crop planting, SO4-S fertilizer is readily available, whereas elemental sulfur must be oxidized to SO4-S by soil microbes prior to plant uptake. Furthermore, the oxidation process to convert elemental sulfur into SO4-S is slow and requires soil environmental conditions (i.e., temperature and moisture) are suitable for aerobic microbial activity (Havlin et al., 2013). However, unlike SO4-S, elemental sulfur is not mobile in the soil and will not readily leach, thus it is commonly used in fall applications. Although a combination of both SO4-S and elemental S may be useful to provide both an immediate and prolonged source of S (Norton et al. 2013), grain yield response to elemental S or granular (SO4-S + elemental S) fertilizer application is inconsistent in past research. In a review of laboratory, greenhouse, and field studies of S fertilizer sources, Chien et al. (2016) concluded granular fertilizers containing elemental S or a combination of elemental S and ammonium sulfate provides less available S than traditional SO4-S based fertilizer sources for field crops within the first year of S 20 application. However, Purucker and Steinke (2020) observed the application of a granulated SO4-S + elemental S) fertilizer increased grain S accumulation by 8% potentially due to delayed S availability from elemental S. 21 LITERATURE CITED 22 LITERATURE CITED Akter, Z., Lupwayi N.Z., and Balasubramanian P.M. (2017). Nitrogen use efficiency of irrigated dry bean (Phaseolus vulgaris L.) genotypes in southern Alberta. Canadian Journal of Plant Science, 97(4): 610-619. Alessi, J., and Power, J.F. (1982). Effects of plant and row spacing on dryland soybean yield and water-use efficiency. Agronomy Journal, 74:851-854. Andrews, M., Raven, J.A., Lea, P.J., and Sprent, J.I. (2005). A role for shoot protein in shoot– root dry matter allocation in higher plants. Ann. Bot., (London) 97:3–10. Argaw, A., and Akuma, A. (2015). Rhizobium leguminosarum bv. viciae sp. inoculation improves the agronomic efficiency of N of common bean (Phaseolus vulgaris L.). Environ Syst Res., 4, 11. Balboa, G.R., Sadras, V.O., and Ciampitti, I.A. (2018). Shifts in soybean yield, nutrient uptake, and nutrient stoichiometry: A historical synthesis-analysis. Crop Science, 58:43-54. Barber, S.A. (1978). Growth and nutrient uptake of soybean roots under field conditions. Agronomy Journal, 70:457-461. Barker, D.W., and J.E. Sawyer. (2005). Nitrogen application to soybean at early reproductive development. Agronomy Journal, 97,615-619. Blaylock, A.D. (1995). Navy bean yield and maturity response to nitrogen and zinc, Journal of Plant Nutrition, 18:1, 163-178. Bender, R.R., Haegele, J.W. and Below, F.E. (2015). Nutrient Uptake, Partitioning, and Remobilization in Modern Soybean Varieties. Agronomy Journal, 107: 563-573. Bharati, M.P., Whigham, D.K., and Voss, R.D. (1986). Soybean response to tillage and nitrogen, phosphorus, and potassium fertilization. Agronomy Journal, 78:947-950. Bluck, G.M., Lindsey, L.E., Dorrance, A.E., and Metzger, J.D. (2015). Soybean Yield Response to Rhizobia Inoculant, Gypsum, Manganese Fertilizer, Insecticide, and Fungicide. Agronomy Journal, 107: 1757-1765. Board, J. (2000). Light interception efficiency and light quality affect yield compensation of soybean at low plant populations. Crop Science, 40:1285-1294. 23 Borges, R., and Mallarino, A.P. (2000). Grain yield, early growth, and nutrient uptake of no-till soybean as affected by phosphorus and potassium placement. Agronomy Journal, 92:380- 388. Borst, H.L., and Thatcher, L.E. (1931). Life history and composition of the soybean plant. Bull. 494. Ohio Agricultural Experiment Station, p. 1-96. Bundy, L.G., Tunney, H., Halvorson, A.D. (2005). agronomic aspects of phosphorus management. In: J.T. Sims, A.N. Sharpley, editors, Phosphorus: Agriculture and the environment, Agron. Monogr. 46. ASA, CSSA, and SSSA, Madison, WI. p. 685-727. Carpenter, A.C., and Board, J.E. (1997a). Branch yield components controlling soybean yield stability across plant populations. Crop Science, 37:885-891. Carpenter, A.C., and Board, J.E. (1997b). Growth dynamic factors controlling soybean yield stability across plant populations. Crop Science, 37:1520-1526. Carpenter, Kurt, "Effect of mechanical cutting, planting population and foliar fungicide on soybean white mold and yield" (2020). Creative Components. 578. https://lib.dr.iastate.edu/creativecomponents/578 Chekanai, V., Chikowo, R., and Vanlauwe, R. (2018). Response of common bean (Phaseolus vulgaris L.) to nitrogen, phosphorous, and rhizobia inoculation across variable soils in Zimbabwe. Agriculture, Ecosystems, & Environment, 266: 167-173. Chen, G., and Wiatrak, P. (2011). Seeding rate effects on soybean height, yield, and economic return. Agronomy Journal., 103:1301-1307. Chien, S.H., Teixeira, L.A., Cantarella, H., Rehm, G.W., Grant, C.A. and Gearhart, M.M. (2016). Agronomic Effectiveness of Granular Nitrogen/Phosphorus Fertilizers Containing Elemental Sulfur with and without Ammonium Sulfate: A Review. Agronomy Journal, 108: 1203-1213. Clover, M.W., and Mallarino, A.P. (2013). Corn and soybean tissue potassium content responses to potassium fertilization and relationships with grain yield. Soil Science Society of America Journal, 77:630-642. Coleman, R. (1966). The importance of sulfur as a plant nutrient in world crop production. Soil Science, 101:230-239. Corassa, G. M., Amado, T. J. C., Strieder, M. L., Schwalbert, R., Pires, J. L. F., Carter, P. R., and Ciampitti, I. A. (2018). Optimum Soybean Seeding Rates by Yield Environment in Southern Brazil. Agronomy Journal, 110:2430-2438. 24 Cox, W.J., Cherney, J.H., and Shields, E. (2010). Soybeans compensate at low seeding rates but not at high thinning rates. Agronomy Journal, 102:1238-1243. Culman, S., Fulford, A., Camberato, J., and Steinke, K. (2020). Tri-State Fertilizer Recommendations. Bulletin 974. College of Food, Agricultural, and Environmental Sciences. Columbus, OH: The Ohio State University. De Bruin, J.L., and Pedersen, P. (2008a). Effect of row spacing and seeding rate on soybean yield. Agronomy Journal, 100:704-710. De Bruin, J.L., and Pedersen, P. (2008b). Soybean seed yield response to planting date and seeding rate in the Upper Midwest. Agronomy Journal, 100:696-703. deMooy, C. J., Pesek J., and Spaldon E. (1973). Mineral-nutrition of soybeans, p. 267-352. In B. E. Caldwell (ed.) Soybeans: Improvement, production and uses. ASA No. 16. Divito, G. A., and Sadras, V. O. (2014). How do phosphorus, potassium and sulphur affect plant growthand biological nitrogen fixation in crop and pasture legumes? A meta-analysis. Field Crop Res., 156, 161–171. Eckert, F.R., Kandel, H.J., Johnson, B.L., Rojas‐Cifuentes, G.A., Deplazes, C., Vander Wal, A.J. and Osorno, J.M. (2011). Row Spacing and Nitrogen Effects on Upright Pinto Bean Cultivars under Direct Harvest Conditions. Agronomy Journal, 103: 1314-1320. Edje, O.T., Mughogho, L.K. and Ayonoadu, U.W.U. (1975), Responses of Dry Beans to Varying Nitrogen Levels1. Agronomy Journal, 67: 251-255. Egli, D.B. (1988). Plant density and soybean yield. Crop Science, 28:977-98. Egli, D.B., and Cornelius, P.L. (2009). A regional analysis of the response of soybean yield to planting date. Agronomy Journal, 101:330-335. Enderson, J.T., Mallarino, A.P., and Haq, M.U. (2015). Soybean yield response to foliar-applied micronutrients and relationships among soil and tissue tests. Agronomy Journal, 107:2143-216. Fageria, N.K., Melo, L.C., Ferreira, E. P. B., Oliveira, J. P., and Knupp, A. M. (2014). Dry Matter, Grain Yield, and Yield Components of Dry Bean as Influenced by Nitrogen Fertilization and Rhizobia. Communications in Soil Science and Plant Analysis, 45:1, 111-125. Fageria, N.K., Melo, L.C., and Oliveira, J. de. (2013). Nitrogen Use Efficiency in Dry Bean Genotypes. Journal of Plant Nutrition, 36:14, 2179-2190. 25 Fageria N.K., Baligar, V.C., and Jones, C.A. (2011). Growth and mineral nutrition of field crops. 3ª ed. Boca Raton, CRC Press. 586 p. Faghire, M., Bargaz, A., Farissi, M., Palma, F., Mandri, B., Lluch, C., et al. (2011). Effect of salinity on nodulation, nitrogen fixation and growth ofcommon bean (Phaseolus vulgaris) inoculated with rhizobial strains isolated from the Haouz region of Morocco. Symbiosis 55, 69–75. Farid, M., Earl, H.J. and Navabi, A. (2016). Yield Stability of Dry Bean Genotypes across Nitrogen‐Fixation‐Dependent and Fertilizer‐Dependent Management Systems. Crop Science, 56: 173-182. Farmaha, B.S., Fernández, F.G., and Nafziger, E.D. (2011). No-till and strip-till soybean production with surface and subsurface phosphorus and potassium fertilization. Agronomy Journal, 103:1862-1869. Fixen, P.E., Brulsema, T.W., Jensen, T.L., Mikkelsen, R.L., Murrell, T.S., Phillips, S.B. et al. (2010). The fertility of North American soils, Better Crops Plant Food, 94:6–8. Franzen, D.W. (2017) Fertilizing Pinto, Navy, and Other Dry Edible Bean. SF720, Fargo, ND: North Dakota State University Extension. Frederick, J.R., Camp, C.R., and Bauer, P.J. (2001). Drought-stress effect on branch and mainstem seed yield and yield components of determinate soybean. Crop Science. 41:759–763. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2017a). Dry matter and nitrogen uptake, partitioning, and removal across a wide range of soybean seed yield levels. Crop Science, 57:2170-2182. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2017b). Phosphorus and potassium uptake, partitioning, and removal across a wide range of soybean seed yield levels. Crop Science, 57:2193-2204. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2018). Secondary and micronutrient uptake, partitioning, and removal across a wide range of soybean seed yield levels. Agronomy Journal, 110:1328-1338. George, T. and Singleton, P. (1992). Nitrogen Assimilation Traits and Dinitrogen Fixation in Soybean and Common Bean. Agronomy Journal, 84: 1020-1028. 26 Glowacka, A., Gruszecki, T., Szostak, B., and Michalek, S. (2019). The response of common bean to sulphur and molybdenum fertilization. International Journal of Agronomy 2019: Article ID 3830712. Gutiérrez Boem, F.H., Prystupa, P., Ferraris, G. (2007). Seed number and yield determination in sulfur deficient soybean crops. Journal of Plant Nutrition, 30, 93-104. Hairston, J.E., Jones, W.F., McConnaughey, P.K., Marshall, L.K., and Gill, K.B. (1990). Tillage and fertilizer effects on soybean growth and yield on three Mississippi soils. Journal of Production Agriculture, 3:317-323. Ham, G.E., Liener, I.E., Evans, S.D., Frazier, R.D., and Nelson, W.W. (1975). Yield and composition of soybean seed as affected by N and S fertilization. Agronomy Journal, 67:293-297 Hammond, L.C., Black, C.A., and Norman, A.G. (1951). Nutrient uptake by soybeans on two Iowa soils. Res. Bull. 384. Hankinson, M.W., Lindsey, L.E, and Culman, S.W. (2015). Effect of planting date and starter fertilizer on soybean grain yield. Crop, Forage & Turfgrass Management, 1:2015-0178. Hanway, J.J., and Weber, C.R. (1971a). Accumulation of N, P, and K by soybean (Glycine max (L.) Merrill) Plants. Agronomy Journal, 63:406-408. Hanway, J.J., and Weber, C.R. (1971b). Dry matter accumulation in eight soybean (Glycine max (L.) Merrill) varieties. Agronomy Journal, 63:227-230. Hanway, J.J., and Weber, C.R. (1971c). Dry matter accumulation in soybean (Glycine max (L) Merrill) plants as influenced by N, P, and K fertilization. Agronomy Journal, 63:263-266. Hanway, J.J., and Weber, C.R. (1971d). N, P, and K percentages in soybean (Glycine max (L.) Merrill) plant parts. Agronomy Journal, 63:286-290. Hanway, J. J., Johnson, J. W. (1985). Potassium Nutrition of Soybeans. In: R. D. Munson, editor, Potassium in Agriculture, ASA, CSSA, SSSA, Madison, WI. p. 753-764. Harder, D.B., Sprague, C.L., and Renner, K.A. (2007). Effect of soybean row width and population on weeds, crop yield, and economic return. Weed Technology, 21:744-752. Hardy, R.W.F., Burns, R.C., Hebert, R.R., Holsten, R.D., and Jackson, E.K. (1971). Biological nitrogen fixation: A key to world protein. p. 561- 590. In T.A. Iie and E.G. Mulder (ed.) Biological nitrogen fixation in natural and agricultural habitats. Plant Soil Spec. Martinus Nijhoff, The Hague, the Netherlands. 27 Harper, J.E., and Gibson, A.H. (1984). Differential nodulation tolerance to nitrate among legume species. Crop Science, 24:797–801. Havlin, J. L., Tisdale, S. L., Beaton, J. D., and Nelson, W. L. (2014). Soil fertility and fertilizers: An introduction to nutrient management (8th ed.). Upper Saddle River, NJ: Pearson Prentice Hall. Hitsuda, K., Toriyama, K., Subbarao, G.V. and Ito, O. (2008). Sulfur Management for Soybean Production. In J. Jez (Ed.), Sulfur: A Missing Link between Soils, Crops, and Nutrition, (pp. 117-142), Madison, WI: ASA, CSSA, and SSSA. Hitsuda, K., Yamada, M. and Klepker, D. (2005). Sulfur Requirement of Eight Crops at Early Stages of Growth. Agronomy Journal, 97: 155-159. Hergert, G.W. (2013). Fertilizer Management for Dry Edible Beans. G1713, Lincoln, NE: University of Nebraska-Lincoln Extension of Agriculture and Natural Resources. Hymowitz, T., and Shurtleff, W.R. (2005). Debunking soybean myths and legends in the historical and popular literature. Crop Science, 45:473-476. Imsande, J. (1989). Rapid dinitrogen fixation during soybean pod filling enhances net photosynthetic output and seed yield: A new perspective. Agronomy Journal, 81:549– 556. Ishiguro, M., and Makino, T. (2011). Sulfate adsorption on a volcanic ash soil (allophanic Andisol) under low pH conditions. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 384:121-125. Kaiser, D.E., and Kim, K. (2013). Soybean response to sulfur fertilizer applied as a broadcast or starter using replicated strip trials. Agronomy Journal, 105:1189-1198. Karasu, A., Oz, M., and Dogan, R. (2011). The effect of bacterial inoculation and different nitrogen doses on yield and yield components of some dwarf dry bean cultivars (Phaseolus vulgaris l.). Bulg. J. Agric. Sci., 17: 296-305. Kluthcouski, J., Aidar, H., Thung, M., Oliveira, F.R.A. and Cobucci, T. (2005). Early nitrogen management in the main annual crops. Documentos Embrapa Arroz e Feijão, 188. (In Portuguese.) Embrapa Arroz e Feijão, Santo Antônio de Goiás, GO, Brazil. Koger, C.H. (2009). Optimal plant populations/seeding rates for soybean. Mississippi State Univ. Ext. Serv., Mississippi State, MS. 28 Kumarasinghe, K.S., Kirda, C., Mohamed, A.R.A.G., Zapata, F., and Danso, S. K. A. (1992). 13C isotope discrimination correlates with biological nitrogen fixation in soybean (Glycine max (L.) Merrill). Plant Soil, 139, 145–147. Lee, C.D., Egli, D.B., and TeKrony, D.M. (2008). Soybean response to plant population at early and late planting dates in the Mid-South. Agronomy Journal, 100:971-976. Liebman, M., Corson, S., Rowe, R.J. and Halteman, W.A. (1995), Dry Bean Responses to Nitrogen Fertilizer in Two Tillage and Residue Management Systems. Agronomy Journal, 87: 538-546. Long, S.P., Ainsworth, E.A., Leakey, A.D.B., Nosberger, J., and Ort, D.R. (2006). Food for thought: Lower-than-expected crop yield stimulation with rising CO2 concentrations. Science, 312:1918– 1921. Mallarino, A.P., Webb, J.R., and Blackmer, A.M. (1991). Soil test values and grain yields during 14 years of potassium fertilization of corn and soybean. Journal of Production Agriculture, 4:560-567. Marschner, H. (1998). Beneficial elements. Mineral nutrition of higher plant. 2nd ed. New York: Academic Press. pp 403417. McGrath, S.P., and Zhao, F.J. (1995). A risk assessment of sulphur deficiency in cereals using soil and atmospheric deposition data. Soil Use Manage., 11:110–114. Miklas, P.N., Porter, L.D., Kelly, J.D. et al. (2013). Characterization of white mold disease avoidance in common bean. Eur J Plant Pathol., 135, 525–543. Mills, H.A. and Jones Jr., J.B. (1996). Plant Analysis Handbook II. A Practical Sampling, Preparation, Analysis, and Interpretation Guide. Micro-Macro Publishing, Athens. Moraghan, J.T., Lamb, J.A. and Albus, W. (1991). Nitrogen Fertilizer Requirements of Navy Beans in the Northern Great Plains. Journal of Production Agriculture, 4: 204-208. Morse, W., Cartter, J., and Hartwig, E. (1950). Soybean production for hay and beans. USDA Farmers’ Bulletin 2024: 1-15. Muchow, R.C. (1985). Phenology, seed yield, and water use of grain legumes grown under different soil water regimes in a semi-arid tropical environment. Field Crops Res., 11:81– 97. Naeve, S.L., and Shibles, R.M. (2005). Distribution and mobilization of sulfur during soybean reproduction. Crop Science, 45:2540-2551. 29 Nascente, A.S., Stone, L.F., and Melo, L.C. (2017). Common bean grain yield as affected by sulfur fertilization and cultivars. Revista Ceres, 64(5), 548-552. National Oceanic and Atmospheric Administration. (2014). National climatic data center. NOAA. http://www.ncdc.noaa.gov Nelson, K.A., Motavalli, P.P., and Nathan, M. (2005). Response of no-till soybean [Glycine max (L.) Merr.] to timing of preplant and foliar potassium applications in a claypan soil. Agronomy Journal, 97:832-838. Norton, R., Mikkelsen, R., and Jensen, T. (2013). Sulfur for plant nutrition. Better Crops Plant Food, 97: 10– 12. Oliver, S. and Barber, S. A. (1966). An evaluation of the mechanisms governing the supply of Ca, Mg, K, and Na to soybean roots (Glycine max.). Soil Science Society of America. Proc., 30, 82–86 Oltmans, R. R., and Mallarino, A. P. (2015). Potassium Uptake by Corn and Soybean, Recycling to Soil, and Impact on Soil Test Potassium. Soil Science Society of America, 79:314-327. Pandurangan, S., Sandercock, M., Beyaert, R., Conn, K.L., Hou, A., and Marsolais, F. (2015). Differential response to sulfur nutrition of two common bean genotypes differing in storage protein composition. Frontiers in Plant Sciences, vol. 6, p. 92, 2015. Parvej, M.R., Slaton, N.A., Purcell, L.C., and Roberts, T.L. (2016). Soybean yield components and seed potassium concentration responses among nodes to potassium fertility. Agronomy Journal, 108:854-863. Pereira, P.A.A., Miranda, B.D., Attewell, J.R. et al. (1993). Selection for increased nodule number in common bean (Phaseolus vulgaris L.). Plant Soil, 148, 203–209. Philbrook, B. D., Oplinger, E.S., and Freed, B. E. (1991). Solid-Seeded Soybean Cultivar Response in Three Tillage Systems. Journal of Production Agriculture, 4:86-91. Pias, O.H.C., Tiecher, T., Cherubin, M.R., Mazurana, M., and Bayer, C. (2019). Crop yield responses to sulfur fertilization in Brazilian no-till soils: a systematic review. Rev Bras Cienc Solo., 43:e0180078. Piha, M.I. and Munns, D.N. (1987). Nitrogen Fixation Capacity of Field‐Grown Bean Compared to Other Grain Legumes1. Agronomy Journal, 79: 690 696. Purucker, T, Steinke, K. (2020). Soybean seeding rate and fertilizer effects on growth, partitioning, and yield. Agronomy Journal, 112: 2288– 2301. 30 Quinn, D. and Steinke, K. (2019). Comparing High‐ and Low‐Input Management on Soybean Yield and Profitability in Michigan. Crop, Forage & Turfgrass Management, 5: 1-8 190029. Ralston, J., Imsande, J. (1983). Nodulation of hydroponically grown soybean plants and inhibition of nodule development by nitrate. J. Exp. Bot., 34 1371–1378. 10.1093/jxb/34.10.1371. Raun, W. R., and Johnson, G. V. (1999). Improving nitrogen use efficiency for cereals production. Agronomy Journal, 91, 357–363. Reinprecht, Y., Schram L., Marsolais, F., Smith, T.H., Hill, B., and Pauls, K.P. (2020). Effects of Nitrogen Application on Nitrogen Fixation in Common Bean Production. Front. Plant Sci., 11:1172. Rose, I.A., Felton, W.L., and Banks, L.W. (1981). Responses of four soybean varieties to foliar zinc fertilizer. Aust. J. Exp. Agric. Anim. Husb., 21:236–240. Rowntree, S.C., Suhre, J.J., Weidenbenner, N.H., Wilson, E.W., Davis, V.M., Naeve, S.L., Casteel, S.N., Diers, B.W., Esker, P.D., Specht, J.E. and Conley, S.P. (2013). Genetic Gain × Management Interactions in Soybean: I. Planting Date. Crop Science, 53: 1128- 1138. Ruiz, J.M., Rivero, R.M., and Romero L. (2005). Regulation of Nitrogen Assimilation by Sulfur in Bean, Journal of Plant Nutrition, 28:7, 1163-1174. Sale, P.W.G., and Campbell, L.C. (1986). Yield and composition of soybean seed as a function of potassium supply. Plant Soil, 96:317–325. Salvagiotti, F., Cassman, K.G., Specht, J.E., Walters, D.T., Weiss, A., and Dobermann, A. (2008). Nitrogen uptake, fixation and response to fertilizer N in soybeans: A review. Field Crops Research, 108:1-13. Sawyer, J.E., and Barker, D.W. (2002). Corn and soybean response to sulfur application on Iowa soils. In: Proceedings of the 32nd North Central Extension–Industry Soil Fertility Conference, Des Moines, IA. 20–21 Nov. 2002. Potash and Phosphate Inst., Brookings, SD. p. 157–163. Schlegel, A.J., and Grant, C.A. (2006). Soil Fertility. In: G.A. Peterson, P.W. Unger, W.A. Payne, editors, Dryland agriculture, Agron. Monogr. 23. ASA, CSSA, SSSA, Madison, WI. p. 141-194. 31 Schmitt, M.A., Lamb, J.A., Randall, G.W., Orf, J.H., and Rehm, G.W. (2001). In-season fertilizer nitrogen applications for soybean in Minnesota. Agronomy Journal, 93:983-988. Schnug, E., and Haneklaus, S. (2005). In L.J. de Kok and E. Schnug (eds.) Proc. First Sino- German workshop on aspects of sulfur nutrition of plants. Braunschweig, Federal Agricultural Research Centre (FAL), p.131. Sexton, P.J., N.C. Paek, and R. Shibles. (1998). Soybean sulfur and nitrogen balance under varying levels of available sulfur. Crop Science, 38:975-982 Shibles, R.M., and Weber, C.R. (1966). Interception of solar radiation and dry matter production by various soybean planting patterns. Crop Science, 6:55-59. Shibles, R., and Sundberg, D.N. (1998). Relation of leaf nitrogen content and other traits with seed yield of soybean. Plant Prod. Sci., 1:3–7. Sinclair, T.R. (1998). Historical changes in harvest index and crop nitrogen accumulation. Crop Science, 38:638–643. Singh, S. P., and Schwartz, H. F. (2010). Breeding common bean for resistance to diseases: a review. Crop Science, 50, 2199–2223. Slaton, N. A., Roberts, T. L., Golden, B. R., Ross, W. J., and Norman, R. J. (2013). Soybean Response to Phosphorus and Potassium Supplied as Inorganic Fertilizer or Poultry Litter. Agronomy Journal, 105:812-820. Soratto, R.P., Perez, A.A.G. and Fernandes, A.M. (2014). Age of No‐Till System and Nitrogen Management on Common Bean Nutrition and Yield. Agronomy Journal, 106: 809-820. Specht, J.E., Diers, B.W., Nelson, R.L., de Toledo, J.F.F., Torrion, J.A., and Grassini, P. (2014). Soybean. In: S. Smith, B. Diers, J. Specht, and B. Carver, editors, Yield gains in major U.S. field crops. CSSA Spec. Publ. 33. ASA, CSSA, and SSSA, Madison. p. 311-356. Starling, M.E., Wesley, C., Wood, C.W. and Weaver, D.B. (1998). Starter nitrogen and growth habit effects on late-planted soybean. Agronomy Journal, 90(5): 658-662. Steinke, K., and Bauer, C. (2017). Enhanced efficiency fertilizer effects in Michigan sugarbeet production. Journal of Sugar Beet Research, 54, 2–19. Sulieman, S., Fischinger, S.A., Gresshoff, P. M., and Schulzea, J. (2013). Asparagine as a major factor in the N-feedback regulation of N2 fixation in Medicago truncatula. Physiologia Plantarum, vol. 140, no. 1, pp. 21–31. 32 Sutradhar, A.K., Kaiser, D.E., and Behnken, L.M. (2017). Soybean response to broadcast application of boron, chlorine, manganese, and zinc. Agronomy Journal, 109:1048-1059. Sutradhar, P., Debbarma, M., and Saha, M. (2016). Microwave synthesis of zinc oxide nanoparticles using coffee powder extract and its application for solar cell, Synthesis and Reactivity in Inorganic. Metal-Organic and Nano-Metal Chemistry, 46, 1622-1627. Tamagno, S., Balboa, G.R., Assefa, Y, Kovács, P., Casteel, S.N., Salvagiotti, F., Garciá, F.O., Stewart, W.M., and Ciampitti, I.A. (2017). Nutrient partitioning and stoichiometry in soybean: A synthesis-analysis. Field Crops Res., 200: 18–27. Taylor, R.S., Weaver, D.B., Wood, C.W., and van Santen, E. (2005). Nitrogen Application Increases Yield and Early Dry Matter Accumulation in Late‐Planted Soybean. Crop Science, 45: 854-858. Thilakarathna, M. S., and Raizada, M. N. (2018). Challenges in using precision agriculture to optimize symbiotic nitrogen fixation in legumes: progress, limitations, and future improvements needed in diagnostic testing. Agronomy, 8, 78. USDA-FAS. (2017). Soybeans: World supply and distribution. USDA Foreign Agricultural Service. https://apps.fas.usda.gov. USDA National Agricultural Statistics Service. (2019). USDA-NASS agricultural statistics 2019. USDA-NASS. http://www.nass.usda.gov. USDA National Agricultural Statistics Service. (2020). USDA-NASS agricultural statistics 2020. USDA-NASS. http://www.nass.usda.gov Van Kessel, C., and Hartley, C. (2000). Agricultural management of grain legumes: has it led to an increase in nitrogen fixation? Field Crops Res., 65, 165–181. Vitosh, M.L., Johnson, J.W., and Mengel, D.B. (1995). Tri-State fertilizer recommendations for corn, soybeans, wheat and alfalfa. E2567. East Lansing, MI: Michigan State University Extension. Vitosh, M.L., Warncke, D.D., and Lucas, R.E. (1994). Secondary and micronutrients for vegetables and field crops. Bull. E486. East Lansing, MI: Michigan State University Extension. Warncke, D., Dahl, J., and Jacobs, L. (2009). Nutrient recommendations for field crops in Michigan. Bulletin E2904, East Lansing, MI: Michigan State University Extension. Wilson, R.F. (2004). Seed composition. Soybeans: Improvement, Production, and Uses, 621– 677. 33 Ziska, L.H., and Bunce, J.A. (2007). Predicting the impact of changing CO2 on crop yields: Some thoughts on food. New Phytol., 175:607–618. 34 CHAPTER 2 SOYBEAN SEEDING RATE AND NUTRIENT MANAGEMENT STRATEGIES IMPACT ON PLANT GROWTH AND GRAIN YIELD UNDER IRRIGATED AND NON- IRRIGATED SYSTEMS Abstract Greater nutrient availability may support soybean (Glycine max L. Merr.) yield potential through increases in total dry matter (TDM) production and nutrient uptake. However, it is uncertain if fertilizer application timing and placement strategies across seeding rates under irrigated and non-irrigated conditions can increase grain yield. Two multi-year trials were established near Lansing, MI to investigate soybean dry matter (DM) and nutrient accumulation, and partitioning, grain yield, and net economic return. Seeding rates included 148,000, 297,000, and 445,000 seeds ha-1. Fertilizer strategies were no fertilizer, 168 kg MESZ ha-1 (12-40-0-10-1- N-P-K-S-Zn) applied five centimeters to the side and five centimeters below the seed (5x5) at planting, 150 L of liquid potash (LK) ha-1 (0-0-28-N-P-K) applied using a Y-drop applicator near growth stage V6, 140 L of ammonium polyphosphate (AP) ha-1 (10-34-0-N-P-K) applied using a Y-drop applicator near growth stage R1, and a combination of the MESZ, LK, and AP fertilizer applications (All). Early season (V4) DM and nutrient accumulation significantly increased with seeding rates ≥ 297,000 seeds ha-1 and MESZ in the MESZ and All fertilizer treatment. Seeding rate and fertilizer application did not interact to increase grain yield, indicating seeding rates responded similarly to fertilizer application. The 148,000 seeds ha-1 rate significantly decreased yield at two of four site-years while no yield differences were observed between seeding rates at the remaining two site-years. Fertilizer application significantly influenced total dry matter 35 accumulation in one of four site-years and nutrient accumulation across all site-years but did not impact grain yield. Lack of an interaction between seeding rate and fertilizer application coupled with unrealized yield gains from fertilizer application suggest producers should alternatively focus on other farm management practices rather than supplemental fertilizer application strategies, especially when soil nutrient concentrations are at or above critical. Introduction Increased climate variability combined with volatile soybean commodity prices (i.e. 50% increase from 2020 to 2021) have piqued grower interest for more intensive nutrient management strategies (USDA-NASS, 2021). Additionally, prolonged mid- to late-summer periods with insufficient soil moisture especially during pod formation and grain-fill has practitioners questioning whether supplemental irrigation may also impact fertilizer strategies between irrigated and non-irrigated environments. Seeding rate and fertilizer placement are two influential factors affecting nutrient uptake and grain yield (Purucker and Steinke, 2020). Interplant competition and subsequent total dry matter accumulation may influence nutrient uptake, thus seeding rates that maximize early season dry matter may be able to maintain soybean yield potential during increasingly unpredictable late-season temperature and precipitation fluctuations across the north-central United States (Duncan, 1986; Egli 1988b; Southworth et al., 2000). Although soil P, K, secondary, and micronutrients concentrations in combination with crop responsiveness may largely dictate whether a grain yield response occurs to fertilizer application, few data exist concerning the manipulation of seeding rate, soil moisture (i.e., irrigation), and fertilizer placement and timing on nutrient accumulation, total dry matter partitioning, and grain yield. 36 Earlier soybean planting dates in response to warmer spring air and soil temperatures and reduced tillage practices have prompted greater consideration for the use of starter fertilizers in soybean production systems. In Michigan, starter fertilizer may often be placed in a subsurface band 5 cm below and 5 cm to the side of the seed (5x5) as this positioning reduces the risk for salt injury and increases fertilizer efficiency by placing plant-available nutrients within reach of developing plant roots, which may often result in greater early season vegetative growth and nutrient uptake (Touchton et al., 1986; Vitosh et al., 1995; Rutan and Steinke, 2018). Osborne and Riedell (2006) found starter N increased V3-V4 soybean biomass, plant N, and grain yield in 2 of 3-site-years. Research in Ohio determined diammonium phosphate fertilizer applied in a subsurface band at planting increased V2 growth but did not impact R1 growth or grain yield (Hankinson et al., 2015). Early season soybean responses to starter fertilizer are often thought to be the result of limited early-season biological N fixation (BNF), decreased spring nutrient mineralization and availability (e.g., N and P), and reduced seedling root growth in cool, wet soils (Bergersen, 1958; Hardy et al., 1971; Ray et al., 2005; Warncke et al., 2009; Ciampitti and Salvagiotti, 2018). While N and P are typically the primary nutrients applied in a starter fertilizer, other nutrients including S and Zn have increased in usage due to reductions in atmospheric S deposition, use of high concentration fertilizers and perceived micronutrient deficiencies (McGrath and Zhao, 1995; Chien et al., 2009; Sutradhar et al., 2017). Bluck et al. (2015) found the application of S as gypsum did not influence grain yield but Kaiser and Kim (2013) reported sulfur broadcast or applied in starter increased V5 S plant concentration and uptake, R1 uppermost trifoliate S concentration, grain S concentration, and grain S removal. Sutradhar et al. (2017) found ZnO broadcasted on the soil surface before planting did not increase mean trifoliate Zn concentration or grain yield. Although soil and environmental factors 37 will influence soybean response to starter fertilizer (e.g., soil temperature, moisture, and pH), greater early season vegetative growth and nutrient uptake from starter fertilizer application may support increased yield potential under some conditions (Sorensen and Penas, 1978; Osborne and Riedell, 2006; Purucker and Steinke, 2020). Between 1923 and 2008, soybean grain yield from maturity groups II and III increased at a rate of 23 kg ha-1 year-1 (Rincker et al., 2014). Greater grain yield during this period may partly be due to increased TDM through advancements in genetics and agronomic practices (Specht et al., 1999; De Bruin and Pederson, 2009; Rincker et al., 2014; Rowntree et al., 2014). Rowntree et al. (2014) found genetic improvement in TDM was the product of greater DM accumulation at late reproductive stages (i.e., after the onset of R4) and not vegetative growth. Suhre et al. (2014) determined seed yield was maximized at greater seeding rates for both old and new cultivars, but newer cultivars seeded at lower plant populations demonstrated greater plasticity by producing additional pods on plant branches. When avoiding stress during vegetative growth, decreased seeding rates may achieve similar crop growth rates and grain yield as greater seeding rates while simultaneously reducing seed cost and interplant competition for water and nutrients (Alessi and Power, 1982; Board, 2000). However, greater interplant competition from increased seeding rates generally results in quicker canopy closure, reduced weed emergence, increased soybean growth at early development stages, and some degree of protection against poor seedling emergence (Hamman et al., 2002; Harder et al., 2007; Chen et al., 2011). Previous research quantified nutrient uptake, partitioning, and removal patterns in modern soybean production systems across fertility regimes within a yield range of 3000 to 6000 kg ha-1 (Bender et al., 2015; Gaspar et al. 2017a, 2017b, 2018). Closely resembling DM accumulation, N, P, S and Zn uptake were evenly distributed during vegetative and seed-filling 38 growth phases, emphasizing the importance of sufficient soil nutrient concentrations to accommodate season-long nutrient accumulation (Bender et al., 2015). However, more than 70% of total K uptake has been found to occurr before late reproductive stages and unlike N and P, seed K demands rely heavily on vegetative remobilization after R5 (Bender et al., 2015; Gaspar et al., 2017a, 2017b). Although soybean nutrient requirements are generally field and year specific, higher grain yields often support a greater reliance on continuous soil-derived N, P, and S availability past R5.5 rather than vegetative remobilization (Gaspar et al. 2017a, 2017b, 2018). Greater yields have been associated with additional early season nutrient uptake, higher peak uptake rates, extended nutrient uptake duration, and greater late-season uptake quantities. (Bender et al., 2015; Gaspar et al. 2017a, 2017b, 2018). Peak uptake of N, P, and K generally ranges from R3 to R5, R2 to R4, and R1 to R3, respectively (Bender et al., 2015; Gaspar et al. 2017a, 2017b). In high yield environments (> 5000 kg ha-1), identifying peak uptake periods has been suggested as to guide in-season fertilizer applications (i.e., N, P, and K) for greater synchrony between peak nutrient uptake and late season nutrient availability (Bender et al., 2015; Gaspar et al. 2017a, 2017b, 2018). However, previous research of in-season fertilizer applications was inconsistent. Salvagiotti et al. (2009) hypothesized accelerated leaf senescence due to constrained seed N demand from insufficient soil N and a late season decline in BNF would shorten the duration of crop photosynthesis, thus impacting grain yield. Freeborn et al. (2001) found R3 supplemental N fertilization in yield environments ranging from 2400 to 5300 kg ha-1 did not increase grain yield concluding N supplied via fixation and N mineralization was adequate in the Mid-Atlantic Coastal Plain. In Michigan, Quinn and Steinke (2019) found potassium thiosulfate R1 surface banded at above critical soil test K concentrations did not influence grain yield. Although not soil applied, Haq and Mallarino (2000) observed foliar 39 applying various rates of a commercial 3-8-15 fertilizer tended to increase grain yield when soil or weather conditions reduced plant growth and N, P, and K availability. The objective of this study was to evaluate the effects of seeding rate and fertilizer strategy in both irrigated and non- irrigated medium-textured soils on DM production, nutrient partitioning and accumulation, grain yield, economic return, and whether the potential for greater DM production from decreased seeding rates affected the potential for nutrient accumulation. Materials and Methods Field trials were conducted in 2019 and 2020 at the Michigan State University South Campus Research Farm near Lansing, MI (42º42′37.0″N, 84º28′14.6″W) on an irrigated and non-irrigated Capac Loam soil (fine-loamy, mixed, active, mesic Aquic Glossudalf) and at the Michigan State University AgBioResearch Mason Research Farm near Lansing, MI (42º37′44.2″N, 84º25′56.3″W) on a non-irrigated Conover Loam soil (fine-loamy, mixed, active, mesic Aquic Hapludalfs) in 2020. All sites were previously cropped to corn (Zea mays L.), autumn chisel plowed (20-cm depth), and spring field cultivated (10-cm depth) prior to planting. A Micro Rain (model MR58RLBP) traveling irrigator (Micro Rain, Yukon, OK) provided 16.5 and 20 cm of supplemental water throughout the growing season at times of peak evapotranspiration and low soil moisture at the irrigated site in 2019 and 2020, respectively. Soil samples (20-cm depth) were collected prior to nutrient application, ground to pass through a 2- mm sieve, and analyzed for soil chemical properties (Table 2.01). Full season pest control followed Michigan State University best management practices. At the irrigated 2020 site, pyraclostrobin (carbamic acid, [2-[[[1-94-chlorophenyl)-1H-pyrazol-3- yl]methyl]phenyl]methoxy-, methyl ester) was applied at R3 to prevent foliar soybean diseases. 40 Environmental data were collected using the Michigan State University Enviro-weather (https://enviroweather.msu.edu, Michigan State University, East Lansing, MI). Precipitation and temperature 30-year averages were obtained from the National Oceanic and Atmosphere Administration (NOAA, 2019). Trials were arranged in a randomized complete block split-plot design with four replications. The main plot factor was seeding rate and the subplot factor was fertilizer application. Seeding rates consisted of 148,000, 297,000, and 445,000 seeds ha-1. Plants stands at the irrigated and non-irrigated site were within 10 and 33% of the targeted seeding rates in 2019 and 2020, respectively, as evidence by stand counts (Fehr and Caviness, 1977; Hicks et al., 1990). Fertilizer treatments consisted of a non-fertilized control, 168 kg MicroEssentials® SZ® (MESZ) (Mosaic CO., Plymouth, MN) ha-1 (12-40-0-10-1 N-P-K-S-Zn) applied 5-cm below and 5-cm to the side of the seed (5 x 5), 150 L of liquid potash (LK) ha-1 (0-0-28 N-P-K) applied using a Y-drop applicator near V6, 140 L of ammonium polyphosphate ha-1 (AP) (10-34-0 N-P- K) applied using a Y-drop applicator near R1, and a combination of the MESZ, LK, and AP fertilizer treatments referred to as the (All) treatment. Individual 6-row plots measured 12.2 m in length and 4.6 m in width. The variety ‘S170115’, and ‘S76420724’ (Stine Seed Co., Adel, IA) was planted in 76-cm rows using a Monosem planter (Monosem Inc., Kansas City, KS) in Lansing on 28 May 2019 and on 07 May 2020, respectively. Aboveground plant biomass was sampled from five consecutive plants at V4, R2, R5, and R8 when at least 50% of the crop achieved each respective growth stage (Fehr & Caviness, 1977). Plants were partitioned into leaves, stems and petioles, flowers and pods, and grain (Bender et al., 2015). 1-cm by 1-cm netting was assembled immediately prior to the onset of leaf drop to retain senesced DM. Dry weight was determined by drying plant tissues at 66C to 0% 41 moisture. Total DM accumulation was reported as the sum of all plant components. V4 and R8 aboveground plant components, and R8 grain samples were analyzed for N (AOAC, 1995a), P (AOAC, 1995b), K (AOAC, 1995b), S (AOAC, 1995b), and Zn (AOAC, 1995b). Nutrient accumulation (kg ha-1) was calculated from nutrient concentration, DM accumulation, and plant density. Grain yield, moisture, and test weight were determined by harvesting the center two rows of each plot with a research plot combine (Kincaid Equipment Manufacturing, Haven, KS). Final yield was adjusted to 135 g kg-1 moisture. Economic return was estimated using an average local cash price of $0.32 and $0.51 kg-1 in 2019 and 2020, respectively, and input costs of $109, $810, $111, and $1,030 ha-1 for MESZ, LK, AP, and the All applications, respectively. Nutrient application costs of $3.81 and $29.65 ha-1 were estimated for the 5 x 5 subsurface application and Y-drop application, respectively, using Michigan State University Extension Custom Machine and Work Rate Estimates (Stein, 2019). Seed cost for 140,000 seeds ha-1 was estimated at $50.00. Net economic return was calculated using a partial budget subtracting input cost from gross revenue (i.e., grain price multiplied by yield). Statistical analyses were performed using PROC GLIMMIX in SAS 9.4 (SAS Institute, 2012) at α = 0.10. Site-year, seeding rate, and fertilizer application were considered fixed effects and the replication as random. Normality of residuals were examined using the UNIVARIATE procedure (P ≤ .05). Squared and absolute values of residuals were examined with Levene’s Test to confirm homogeneity of variances (P ≤ .05). Least square means were separated using the LINES option of the slice statement when ANOVA indicated a significant interaction (P ≤ .10). Pearson product-moment correlations were derived using the REG procedure of SAS to investigate the relationship between DM accumulation with grain yield and final DM accumulation with R8 grain nutrient accumulation. 42 Results and Discussion Environmental Conditions Total growing season (May-September) precipitation was within 5% of the 30-yr average across years (Table 2.02). However, mean 2019 monthly precipitation was 29 and 108% above the 30-yr average in May and June, respectively, and 42% and 78% below the 30-yr average for July and August, respectively, creating contrasting early and late-season soil moisture conditions. Mean 2020 monthly precipitation was below the 30-yr average by 16, 42, and 16% in June, July, and August, respectively creating deficit July through August precipitation (i.e., greater than 10% below the 30-yr average) which may have limited vegetative growth, grain-fill, yield potential, and nutrient movement and uptake at the non-irrigated sites. Mean monthly air temperatures across both years were within 2.5 ˚C of the 30-yr average (Table 2.02). Dry Matter Accumulation and Partitioning Poor seedling emergence from soil crusting at the irrigated and non-irrigated 2020 locations reduced plant stands by up to 33% below the targeted seeding rates and possibly limited DM production in 2020 as compared to 2019. However, earlier soybean planting (i.e., 21 d earlier in 2020 than 2019) may have potentially increased 2020 vegetative and reproductive growth periods thereby also increasing DM accumulation (Hu and Wiatrak, 2012). Dry matter accumulation at V4 (kg ha-1) was significantly influenced by seeding rate (P < 0.01) across all site-years (i.e., irrigated and non-irrigated) (Table 2.03, 2.04). As seeding rate increased from 148,000 to 445,000 seeds ha-1 at irrigated and non-irrigated sites, V4 dry matter (V4DM) concomitantly increased. Greater plant populations (e.g., > 125,000 plants ha-1) have been shown to produce less DM plant-1 near 30 d after emergence compared to low plant populations (e.g., ≤ 125,000 plants ha-1) due to decreased plant growth rates (g m−2 d−1) from greater interplant 43 competition (Board, 2000; Purucker and Steinke, 2020). However, results from the current study suggest greater V4DM plant-1 (data not shown) at 148,000 seeds ha-1 was not sufficient to overcome reductions in DM per acre as the result of greater seeding rates (i.e., ≥ 297,000 seeds ha-1). Seeding rate continued to significantly influence DM accumulation until R2 at which point accelerated post-R1 crop growth rates produced no differences in R5 dry matter (R5DM) and R8 total dry matter (R8TDM) (Table 2.03, 2.04). Total R2 dry matter (R2DM) accumulation within seeding rates accounted for 46-53% (irrigated 2019), 45-63% (non-irrigated 2019), 15-28% (irrigated 2020), and 14-23% (non-irrigated 2020) of the season-long total aboveground dry matter (data not shown). Previous research reported diminished aboveground biomass responses from greater seeding rates due to increased competition for water during dry soil conditions (Alessi and Power, 1982; Purucker and Steinke, 2020). In the current study, similar results between seeding rates at the irrigated and non-irrigated sites at R5 despite deficit precipitation (i.e., > 10% below 30-yr average) during July and August in both years suggest lack of moisture likely did not offset the vegetative responses observed at V4 and R2. Instead, greater crop growth rates due to less interplant competition from 148,000 and 297,000 seeds ha-1 may have reduced the DM difference between R2 and R5 (Wells, 1993; Carpenter and Board. 1997a; Egli, 1998a; Ball et al., 2000; De Bruin and Pedersen, 2008; Lee et al., 2008). Although no differences in R8TDM between seeding rates existed, a likely decrease in competition for water from irrigation increased R8TDM 2,978 and 5,081 kg ha-1 across seeding rates in 2019 and 2020, respectively compared to rain-fed conditions. Relative to the treatments which did not receive fertilizer before V4 (i.e., non-fertilized, LK, and LP) the MESZ and All (which only included MESZ by V4 growth stage) treatments produced greater V4DM across site-years (Table 2.03, 2.04). The MESZ is a co-granulated 44 fertilizer containing N, P, S, and Zn and was applied 5 cm below and 5 cm to the side of the seed at planting (i.e., starter fertilizer). Starter fertilizer for soybean may increase early-season vegetative growth due to limited BNF (biological nitrogen fixation) and N mineralization from SOM (soil organic matter) during spring soil conditions (Ray et al., 2006; Osborne and Riedell, 2006; Ciampitti and Salvagiotti, 2018). Previous research reported increased early season vegetative growth from starter N+P, N+P+S, or N+P+S+Zn fertilizers, but further analysis suggested greater early season vegetative growth was primarily due to N rather than P, S, or Zn (Kaiser and Kim, 2013; Hankinson et al., 2015; Purucker and Steinke, 2020). In the current study, cool soil temperatures at planting (13.3-18.2 ˚C) and moderate SOM concentrations (21- 26 g kg-1) may have placed a greater reliance on soil-derived N due to minimal BNF contributions until V2-V4 indicating the potential for N in MESZ fertilizer to increase V4DM (Taylor et al., 2005; Tamagno et al., 2018). Considering that visual P, S, and Zn deficiencies were not observed, soil test P concentrations (20-87 mg kg-1) were sufficient, and few data exist or do not support early-season DM responses to S or Zn application, it is unlikely that P, S, or Zn within MESZ increased V4DM (Boem et al., 2007; Warncke et al., 2009; Kaiser and Kim, 2013; Hankinson et al., 2015). The 2019 R2DM, R5DM, and R8TDM were significantly influenced by fertilizer strategy at the irrigated site compared to R2DM and R5DM without irrigation (Table 3, 4). Non-irrigated results agree with Purucker and Steinke (2020) who found early-season DM differences from MESZ application likely diminished post-R1 due to accelerated crop growth rates which peak near R3-R4 (Bender et al., 2015; Gaspar et al., 2017a). In 2019, August precipitation was 6.4 cm below the 30-yr average, indicating that continued DM differences with irrigation may be attributed to supplemental water to help sustain biomass production during critical reproductive growth periods (i.e., pod- and seed-fill) (Andriani et al. 1991; Torrion et al., 45 2014; Wingeyer et al., 2014). Within fertilizer strategy, R8TDM ranged from 6507-8385 kg ha-1 (irrigated 2019) and 4988-6401 kg ha-1 (non-irrigated 2019) (Table 2.03, 2.04). The All fertilizer treatment increased irrigated R8TDM 24% compared to the non-fertilized control, but no differences occurred between the remaining fertilizer strategies and the non-fertilized control suggesting that the MESZ component within the All treatment largely caused R8TDM differences. In 2020, R2DM and R5DM were significantly influenced by fertilizer strategy at the irrigated site compared to only R2DM without irrigation (Table 2.03, 2.04). Similar to 2019, supplemental water likely influenced late-season DM differences at the irrigated site but white mold infection late into the 2020 growing season affected DM accumulation beyond R5 due to early plant senescence and death (data not shown) (Chen and Wang, 2005; Mueller et al., 2017). With supplemental water extending early-season DM differences later into the growing season, growers solely focusing on intensive management and high yield potential (i.e., irrigation, higher plant populations, and greater soil fertility) may need to consider risks for greater disease occurrence (e.g., white mold) and remember that factors such as cultivar selection, increased row width, and foliar fungicide applications may be required to mitigate disease incidence (Grau et al., 1994). Seeding rate and fertilizer application affected V4DM partitioning (data not shown). Averaged across seeding rate and fertilizer treatments, V4DM partitioned between leaves or stems/petioles ranged from 64-77% and 23-36%, respectively for irrigated 2019 and 2020 compared to 66-72% and 28-34% for non-irrigated 2019 and 2020. Except for the non-irrigated 2020 site, low seeding rates significantly increased the proportion of V4DM partitioned to leaves and decreased the proportion of V4DM partitioned to stems/petioles compared to increased seeding rates (i.e., ≥ 297,000 seeds ha-1). Greater early-season V4DM partitioning to leaf tissue 46 from the 148,000 seeds ha-1 rate was likely due to decreased interplant competition that supported greater light interception and efficiency (i.e., photosynthetic capacity), critical to the compensatory yield ability of soybean at low plant populations (Carpenter and Board, 1997b; Ball et al., 2000; Board, 2000). In 2019, MESZ and All (which only included MESZ by V4 growth stage) applications significantly increased the proportion of V4DM partitioned to stems/petioles and decreased the proportion of V4DM partitioned to leaves compared to the non- fertilized control (data not shown). Although early-season DM accumulation is largely partitioned into leaf tissue until the initiation of reproductive growth (Gaspar et al., 2017a), results indicate greater V4DM accumulation from MESZ was the result of increased stem/petiole growth. Regardless of DM partitioning, greater early-season DM from sub-surface fertilizer application provide greater soybean nutrient accumulation. Averaged across seeding rate and fertilizer treatments, R8TDM partitioned to leaves, stems/petioles, pods, or grain ranged from 11-17%, 29-41%, 13-18%, and 25-40%, respectively for irrigated 2019-2020 compared to 12-16%, 22-27%, 15-21%, 40-44% for non-irrigated 2019- 2020 (data not shown). Environmental factors including precipitation will influence DM allocation, but the differences between irrigated and non-irrigated 2019 R8TDM partitioning were minimal despite poor pod and seed-fill conditions from below average August precipitation (i.e., 78% below the 30-yr average) (Chen and Wiatrak, 2010). However, R8TDM partitioned to grain (i.e., harvest index) appeared to be greater for non-irrigated (42-44%) than irrigated (38- 40%) soybeans, suggesting irrigation produced additional biomass in excess of soybean growth and yield requirements. While the 148,000 seeds ha-1 rate produced more stem/petiole R8DM per plant (data not shown), greater seeding rates (i.e., ≥ 297,000 seeds ha-1) increased the proportion of R8TDM partitioned to stems/petioles at three of four site-years. Moreover, plant height and 47 stem diameter (data not shown) indicate additional stem/petiole DM per plant from 148,000 seeds ha-1 was due to a thicker rather than elongated main stem and the production of additional lateral branches. In two of three site-years, where seeding rate influenced stem/petiole partitioning, the proportion of R8TDM partitioned to grain was maximized by 148,000 seeds ha- 1 . Individual plant data (i.e., R8TDM, R5 stem diameter, and R5 plant height) combined with R8TDM partitioning results suggest the potential for the 148,000 seeds ha-1 rate to remobilize a greater proportion R8TDM from the main stem and lateral branches to the grain existed, thus increasing harvest index compared to increased seeding rates (i.e., ≥ 297,000 seeds ha-1). Bender et al. (2015) found approximately twice the amount of K was remobilized from stem than leaf tissue, indicating greater stem/petiole remobilization from decreased seeding rates (i.e., 148,000 seeds ha-1) may serve to increase the relative proportion of grain K content to total nutrient accumulation. Differences in R8TDM partitioning due to fertilizer strategy were minimal and agree with Bender et al. (2015) and Purucker and Steinke (2020). Due to dry matter partitioning largely regulating nutrient partitioning (Marcelis, 1996; Engels et al., 2012), lack of R8TDM differences within the fertilizer treatment suggest no differences in R8 nutrient partitioning should be expected (data not shown). Nutrient Accumulation Nitrogen, P, K, S, and Zn uptake (kg ha-1) at V4 across irrigated and non-irrigated sites were less than 10% and 19% of total N, P, K, S, and Zn uptake in 2019 and 2020, respectively, closely resembling the results from Bender et al. (2015) (Table 2.05, 2.06). The 445,000 seeds ha-1 rate along with MESZ and All (which only included MESZ by V4 growth stage) treatments generally increased early-season (V4) aboveground N, P, K, S and Zn accumulation (kg ha-1) and the percentage of season-long N, P, K, S, and Zn accumulation at V4 across site-years (data not 48 shown). Correlation analysis indicated a positive relationship between V4DM and N, P, K, S, and Zn accumulation (r = 0.85-0.99, P < 0.01), suggesting greater DM production from the 445,000 seeds ha-1 rate or the MESZ, and All (which only included MESZ by V4 growth stage) fertilizer treatments may have facilitated greater nutrient uptake (Bender et al., 2015). Gaspar et al. (2017a, 2017b, 2018) reported greater grain yields (i.e., 5500 kg ha-1) and greater total nutrient uptake were associated with a shorter “lag phase” during the first 20 DAE. A greater percentage of season-long nutrient accumulation at V4 suggests that either the 445,000 seeds ha-1 rate or MESZ and All (which only included MESZ by V4 growth stage) treatment application likely reduced the “lag phase” of soybean nutrient accumulation thereby increasing greater early season nutrient accumulation and the potential for late-season vegetative nutrient remobilization. However, previous research indicated that most grain nutrient demand was removed from the soil during grain-fill rather than vegetative remobilization (Bender at al., 2015; Gapsar et al., 2017a, 2017b, 2018) indicating greater early-season nutrient uptake may not always translate into greater grain yield. Total R8 aboveground nutrient accumulation (kg ha-1) was significantly impacted by seeding rate under irrigation 2019 and without irrigation 2020 (Table 2.07, 2.08). Nitrogen was the only nutrient influenced by seeding rate at the irrigated 2019 site compared with N, P, K, and Zn at the non-irrigated 2020 site. Where total N, P, K, S, and Zn accumulation were significantly affected, 297,000 and 445,000 seeds ha-1 generally maximized N, P, K, S, and Zn accumulation. Dry weight accumulation is the foundation for soybean nutrient accumulation (Hanway and Weber, 1971a). No significant differences in R8TDM or before the remobilization of dry matter to the seed at R5 (i.e., R5DM) existed, but variations in R8TDM partitioning within seeding rate 49 may partly be responsible for greater total nutrient accumulation from increased seeding rates (i.e., ≥ 297,000 seeds ha-1). Total aboveground nutrient accumulation (kg ha-1) at R8 was significantly influenced by fertilizer application across site-years (Table 2.07, 2.08). Compared to the non-fertilized control, MESZ, AP, and All fertilizer treatments increased total P accumulation and MESZ and All increased total S accumulation at the irrigated 2019 site while LK increased total N, P, S, and Zn accumulation at the irrigated 2020 site and MESZ increased total S accumulation at the non- irrigated 2020 site. Results suggest fertilizer applications containing P (i.e., MESZ, AP, and All) or S (i.e., MESZ and All) increased P and S uptake by promoting greater soil nutrient availability throughout the soybean growing season (i.e., MESZ and All) or just prior to peak P uptake (i.e., AP). However, lack of grain yield or quality improvements from MESZ, AP, and All fertilizer applications indicate luxury P and S consumption. The S component within MESZ contains one- half elemental S and one-half SO4-S. Chien et al. (2016) reported granular fertilizers containing a combination of elemental S and SO4-S provide less available S after one growing season compared to SO4-S fertilizer sources. However, Degryse et al. (2021) found the total recovery of elemental S over five years will reach or surpass SO4-S under leaching conditions. Although it is unclear whether the elemental S component within MESZ contributed to greater total S accumulation from the MESZ and All applications, slow oxidation of elemental S may reduce the risk for future S deficiencies or the uncertainties associated with soil S availability (Goyal et al., 2021). While LK did increase total N, P, S, and Zn accumulation under irrigation in 2020, LK does not contain N, P, S, or Zn. In 2020, R8TDM was not significantly influenced at the irrigated site but a positive correlation existed between R8TDM and total nutrient accumulation (r = 0.27-0.62, P < 0.05) across site-years, except for total P at the non-irrigated 2019 site. 50 Therefore, greater N, P, S, and Zn accumulation from LK may be the result of non-significant gains in TDM production. However, soil test K concentration in 2020 at the irrigated site (i.e., 128 mg kg) was above the critical level indicating a plant response to K application was unlikely (Cullman et al., 2020). Gaspar et al. (2017b) suggested knowledge of peak uptake rates could direct in-season fertilizer applications to match peak soybean N, P, and K uptake which occur near R4, R3, and R2 respectively. In the current study, the in-season application of AP (20 kg N ha-1 + 66 kg P ha-1) and LK (55 kg K ha-1) only increased total P and K accumulation in one of four site-years, respectively, despite below adequate soil test K concentrations (i.e., < 120 mg kg) in three of four site-years (Culman et al., 2020). In the individual site-years where the in- season application of AP and LK increased total P and K accumulation, MESZ (67 kg P ha-1) also increased total P and K accumulation with no significant differences between MESZ and AP or MESZ and LK. In this specific instance for P, results suggest the application of P before peak P uptake was just as effective at increasing total P accumulation as the sub-surface application of P at planting. However, MESZ does not contain K thus it is likely greater aboveground biomass production from the sub-surface application of N, P, S, and Zn (i.e., MESZ) facilitated increased total K uptake. Nitrogen, P, K, S, and Zn harvest index reported as the percentage of nutrient accumulation partitioned to the grain were significantly impacted by seeding rate and fertilizer treatments across site-years and ranged from 78-86% N, 71-87% P, 49-66% K, 60-76% S, and 65-78% Zn for irrigated 2019-2020 compared to 78-87% N, 79-88% P, 64-88 K, 72-85% S, and 61-80% Zn for non-irrigated 2019-2020 (data not shown). However, differences between seeding rates or fertilizer strategies were minimal and may not be considered biologically significant. The K and S harvest indices were generally greater at the non-irrigated site compared to the irrigated 51 site with a greater percentage of total K and S partitioned to leaves, stems/petioles, and pods (data not shown) rather than to the grain, indicating the potential for luxury consumption. Grain nutrient concentrations across seeding rate and fertilizer treatments ranged from 56-67 g N kg-1, 5.6-6.1 g P kg-1, 19-21 g K kg-1, 3.1-3.4 g S kg-1, and 34-40 mg Zn kg-1 for irrigated 2019-2020 compared to 56-65 g N kg-1, 5.2-5.7 g P kg-1, 18-20 g K kg-1, 2.6-3.1 g S kg-1, and 39-44 mg Zn kg-1 to non-irrigated 2019-2020 (data not shown). Differences between irrigated and non- irrigated grain nutrient concentrations were minimal except for Zn, where Zn concentration across seeding rate and fertilizer treatments ranged from 34-35 mg Zn kg-1 (irrigated 2019), 38- 39 mg Zn kg-1 (non-irrigated 2019), 37-40 mg Zn kg-1 (irrigated 2020), and 39-44 mg kg-1 (non- irrigated 2020). Zinc concentration is a primary factor to help prevent disease (i.e., diarrhea, pneumonia, and malaria) in developing countries worldwide (WHO, 2002; Shrimpton et al., 2005) signifying greater soybean Zn concentrations may offer potential health benefits for food grade soybeans produced under irrigation compared to food grade soybeans produced under non- irrigated conditions. Grain yield No interactions occurred between seeding rate and fertilizer treatment across site-years, indicating fertilizer applications may not require adjustments solely based on early to mid-season changes in DM accumulation due to seeding rate. Grain yields ranged from 4000-5300 kg ha-1 (irrigated 2019-2020) and 2200-3500 kg ha-1 (non-irrigated 2019-2020) (Table 2.09). Increasing seeding rate from 148,000 to 445,000 seeds ha-1 (i.e., 200% increase) under irrigated 2019 and 148,000 to 297,000 seeds ha-1 (i.e., 100% increase) without irrigation 2020 increased grain yield 10 and 20%, respectively. However, grain yield at the non-irrigated 2019 and irrigated 2020 sites was not influenced by seeding rate. Although supplemental water at the irrigated 2019 site may 52 have reduced or eliminated interplant competition for water (Alessi and Power, 1982), incremental increases in seeding rate were not proportional to increases in grain yield possibly indicating other resources (e.g., sunlight) may have limited yield potential at the greater population densities (i.e., 297,000 seeds ha-1) (Duncan, 1986; Elgi, 1988b; Walker et al., 2010). Previous research found lower than recommended seeding rates (i.e., 321,200 seeds ha-1) compensate for reduced plant stands by producing additional pods on plant branches (Cox et al., 2010; Suhre et al., 2014). Lack of grain yield differences and similar pods ha-1 (data not shown) at the non-irrigated 2019 and irrigated 2020 site suggest 148,000 seeds ha-1 compensated for low plant stands by producing additional pods and grain per plant. Due to soil crusting soon after planting, the 148,000 seeds ha-1 rate resulted in a V2 plant stand of 102,000 seeds ha-1 (i.e., 31% decrease) at the non-irrigated 2020 site. In comparison, V2 plant stands at the non-irrigated 2019 site were within 1% of the desired seeding rate (148,000 seeds ha-1). Despite greater August and September precipitation during pod and seed-fill in 2020 than 2019 (Table 2.02), grain yield differences at the non-irrigated site in 2020 between seeding rates were likely due to a considerably low plant stand beyond what compensatory yield on plant branches could overcome. Grain yield was not affected by fertilizer strategy regardless of irrigation in either year. Salvagiotti et al. (2008, 2009) found soybean grain yield was more likely to respond to N applications under a high grain yield environment (> 4500 kg ha-1) due to the late-season decline in soil BNF which when combined with low soil N may be insufficient to satisfy seed N demand. In the current study, average grain yield < 4500 kg ha-1 in three of four site-years suggests BNF and N mineralization had the potential to meet seed N requirements, reducing the likelihood of a grain yield response to N application in MESZ, AP, and All applications (Freeborn et al., 2001). 53 At the irrigated 2020 site, however, average grain yield exceeded 4500 kg ha-1, but N application from MESZ (20 kg N ha-1), AP (20 kg N ha-1), and All (20 kg N ha-1) did not affect grain yield indicating plants were not N deficient. Soil P concentrations across site-years were above critical (i.e., 95 to 97% of maximum yield), indicating grain yield responses to P application were not probable (Warncke et al., 2009). Although deficient soil K concentrations (i.e., < 120 mg K kg-1) (Culman et al., 2020) indicated the potential for a positive grain yield response (other than irrigated 2020) to K application (i.e., LK and All), previous research reported inconsistent yield responses even when STK (soil test potassium) concentrations were considered less than optimum (Clover and Mallarino, 2013). Due to difficulties predicting soil S availability (Goyal et al., 2021), Hitsuda et al. (2004) identified seed concentrations ≤ 2.3 g S kg-1 as deficient. Grain S concentration in the non-fertilized control across site-years (≥ 2.6 g S kg-1) implied S supply was adequate for soybean growth. However, pre-plant soil nutrient analysis indicated soil Zn concentrations were low in three site-years (1.9-3.8 mg Zn kg-1) and recommended the application of 0.8-4.5 kg ha-1 (Zn recommendation (Warncke et al., 2009). Bender et al. (2015) observed increased nutrient uptake, total biomass production, and grain yield when using supplemental fertilization to maintain greater nutrient availability. Although fertilizer application only increased R8TDM at the irrigated 2019 site, correlation analysis indicated a positive relationship between total N, P, K, S, and Zn accumulation and R8TDM (r = 0.27-0.85, P < 0.01-0.03) across site-years with the exception for total P accumulation (r = 0.07, P = 0.60) at the non-irrigated 2019 site. Findings suggest fertilizer application increased biomass production and concomitantly nutrient uptake, thus agreeing with previous literature (Bender et al., 2015). However, grain yield did not increase despite greater R8TDM and nutrient accumulation at respective site-years. Under the current environments tested, supplemental fertilization was 54 utilized as a tool to promote nutrient availability and increase biomass production and nutrient uptake beyond requirements for optimal grain yield (i.e., luxury consumption) regardless of seeding rate. Economic analysis Despite some grain yield differences (e.g., irrigated 2019 and non-irrigated 2020) net economic return was not influenced by seeding rate across site-years, indicating greater grain yield from increased seeding rates (i.e., ≥ 297,000 seeds ha-1) was offset by higher seed cost (Table 2.10). Findings suggest increasing or decreasing seeding rate from 321,200 seeds ha-1 may be practical under the conditions tested (i.e., seed cost and grain price), but growers should consider other risks (i.e., disease, lodging, climate variability, emergence, and harvestability) associated with lower populations prior to altering seeding rate. Net economic return was significantly influenced by fertilizer treatment across site-years. Compared to the non-fertilized control, MESZ, LK, AP, and All applications reduced 2019 net economic return regardless of irrigation. Although no grain yield differences were detected, LK and All decreased net economic return compared to the non-fertilized control at the irrigated and non-irrigated 2020 site. Lack of significant net economic return differences between MESZ, AP, and the non-fertilized control were likely the result of an increase in grain price ($0.19 kg-1) from 2019 to 2020 but constant fertilizer and application costs. An upward shift in grain prices reduces the break-even soybean yield required to cover both fertilizer and application costs (Table 2.11). This decrease in break-even yield illustrates the potential for growers to capitalize on market volatility utilizing fertilizer strategies. 55 Conclusions Seeding rates ≥ 297,000 seeds ha-1 and the sub-surface (5x5) application of MESZ both increased early-season DM and nutrient accumulation thereby providing the potential to improve grain yield. When compared to rain-fed conditions, irrigation sustained early-season DM differences later into the growing season and increased total DM production, nutrient accumulation, and grain yield. Thus supplemental water during mid- to late-summer periods without rainfall may increase the potential for a soybean response to seeding rate and fertilizer application by maintaining accelerated crop growth rates and potentially improving nutrient transport within the soil profile. Although there were no significant differences in R8TDM between 148,000, 297,000, and 445,000 seeds ha-1, the 148,000 seeds ha-1 rate significantly reduced grain yield and total N, P, K, S, or Zn accumulation in two of four site-years compared to seeding rates ≥ 297,000 seeds ha-1 indicating the potential for greater DM production from low plant populations does not always affect the potential for nutrient accumulation. However, a positive correlation between total N, P, K, S, and Zn accumulation and R8TDM (r = 0.27-0.85, P < 0.01-0.03) across respective site-years supports the potential for greater DM production facilitating greater nutrient uptake. Despite plant responses from the strategic placement and timing of fertilizer in addition to seeding rate under irrigated and rain-fed conditions, grain yield was not influenced by fertilizer strategy nor was there an interaction between seeding rate and fertilizer strategy likely due to adequate soil nutrient concentrations except for deficient soil K concentrations in three of four site-years. Results suggest growers should continue focusing on soil resiliency through building or maintaining soil nutrient concentrations over time but may also consider other yield-limiting factors including variety selection, row spacing, planting date, pest and disease control, and soil moisture availability when soil nutrient concentrations are at or 56 above critical. Under high yield environments where seed nutrient demand appears to rely more heavily on nutrient uptake from the soil rather than vegetative remobilization, more research is needed to support the effectiveness of supplemental nutrient applications including rate and timings on soybean yield. Acknowledgements The authors would like to thank the USDA National Institute of Food and Agriculture, the Michigan Soybean Committee, Michigan State University AgBioResearch, and the Michigan State University College of Agriculture and Natural Resources for partial funding and support of this research. In addition, the authors would like to thank Andrew Chomas, research farm staff, and undergraduate research assistants for their technical assistance in the field. 57 APPENDICES 58 APPENDIX A: CHAPTER 2 TABLES Table 2.01. Soil chemical properties and mean nutrient concentrations (0 to 20-cm depth) for irrigated and non-irrigated sites, Lansing, MI, 2019-2020. Soil test valuesa Site Year pH CEC SOM P K S Zn cmolc kg-1 g kg-1 ____________mg kg-1__________ Lansing, irrigated 2019 6.9 7.5 21 38 80 6 2.1 2020 6.5 9.5 26 87 128 9 4.4 Lansing, non-irrigated 2019 7.5 7.5 27 86 94 7 3.8 2020 6.7 8.8 20 20 87 7 1.9 a pH (1:1, soil/water) (Peters et al., 2015); CEC, cation exchange capacity (Warncke et al., 1980); SOM soil organic matter (loss-on-ignition) (Combs and Nathan, 2015); P Phosphorus (Bray-P1) (Frank et al., 2015), K potassium (ammonium acetate method) (Warncke and Brown, 2015), S sulfur (monocalcium phosphate extraction) (Combs et al., 2015), Zn Zinc (0.1 M HCl extraction) (Whitney, 2015). 59 Table 2.02. Monthlya, 30-yr averageb cumulative precipitation and air temperature, and supplemental irrigationc for the soybean-growing season (May-September), Lansing, MI, 2019- 2020. Year May June July August September Total ________________________________________ Precipitation cm________________________________________ 2019 8.5 18.3 5.8 1.8 9.3 43.7 2020 11.0 7.4 4.2 6.9 10.9 40.4 Air Temperature ________________________________________ ˚C ________________________________________ 30-yr avg 8.5 8.8 7.2 8.2 8.9 41.6 2019 13.4 18.3 23.2 20.3 18.5 93.7 2020 13.8 20.2 23.5 21.3 15.8 94.6 ________________________________________ ________________________________________ Irrigation cm 30-yr avg 14.3 19.8 21.9 21.0 16.6 93.6 2019 0 0 5.5 10.0 1.0 16.5 2020 0 2.8 9.9 7.6 0 20.3 a Monthly precipitation and air temperatures collected from MSU Enviro-weather (https://enviroweather.msu.edu). b 30-year averages collected from the National Oceanic and Atmosphere Administration (https://www.ncdc.noaa.gov/cdo-web/datatools/normals). c Supplemental irrigation was applied during times of peak evapotranspiration and low soil moisture at the irrigated site in 2019-2020. 60 Table 2.03. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and R8 aboveground dry matter accumulation, Lansing, MI, 2019. Site Treatment V4 R2 R5 R8 __________________________ -1__________________________ kg ha -1 Irrigated Seeding rate, seeds ha 148,000 159 ca 3167 b 4465 7154 297,000 230 b 3453 b 4885 6834 445,000 310 a 4118 a 5279 7887 P>F <0.01 <0.01 0.22 0.26 Fertilizer Non-fertilized 175 c 3100 c 4461 b 6735 bc b MESZ 295 b 4034 b 4873 b 7916 ab c LK 179 c 2828 c 4241 b 6507 c d AP 148 d 2960 c 4560 b 6914 bc e All 368 a 4973 a 6246 a 8385 a P>F <0.01 <0.01 0.04 0.07 -1 Non-irrigated Seeding rate, seeds ha 148,000 148 c 2393 b 3488 5399 297,000 260 b 3038 a 4016 5848 445,000 317 a 3531 a 4055 5547 P>F <0.01 0.03 0.23 0.73 Fertilizer Non-fertilized 192 b 2643 b 3351 c 4988 MESZ 312 a 3328 a 4576 a 6401 LK 210 b 3092 ab 3826 bc 5718 AP 201 b 2553 b 3587 bc 5535 All 292 a 3320 a 3924 b 5349 P>F <0.01 0.06 <0.01 0.12 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 61 Table 2.04. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and R8 aboveground dry matter accumulation, Lansing, MI, 2020. Site Treatment V4 R2 R5 R8 __________________________ -1__________________________ kg ha -1 Irrigated Seeding rate, seeds ha 148,000 498 ca 1165 b 8982 8555 297,000 805 b 1784 a 10621 10071 445,000 937 a 1960 a 10296 8023 P>F <0.01 <0.01 0.19 0.20 Fertilizer Non-fertilized 674 b 1657 ab 9913 ab 9908 b MESZ 922 a 1907 a 11542 a 8115 c LK 645 b 1363 c 8843 b 8645 d AP 557 b 1459 bc 8919 b 8604 e All 936 a 1795 a 10614 ab 9144 P>F <0.01 <0.01 0.07 0.65 -1 Non-irrigated Seeding rate, seeds ha 148,000 245 c 972 c 7190 7225 297,000 446 b 1454 b 7737 8857 445,000 613 a 1640 a 7143 7589 P>F <0.01 <0.01 0.67 0.13 Fertilizer Non-fertilized 425 b 1297 b 6953 7144 MESZ 528 a 1536 a 7068 7939 LK 419 b 1282 b 8370 8079 AP 371 b 1187 b 6834 8374 All 437 b 1475 ab 7557 7915 P>F 0.07 0.05 0.45 0.76 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 62 Table 2.05. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 aboveground nutrient accumulationa, Lansing, MI, 2019. Site Treatment N P K S Zn _________________ -1_________________ kg ha g ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 5.5 cb 0.6 c 3.7 c 0.4 c 5.4 c 297,000 7.0 b 0.8 b 4.8 b 0.5 b 7.7 b 445,000 9.2 a 1.1 a 6.5 a 0.7 a 11.6 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 5.5 c 0.6 c 4.1 c 0.4 c 5.8 c c MESZ 9.3 b 1.2 b 5.5 b 0.7 b 11.1 b LKd 5.2 c 0.6 c 3.9 c 0.4 c 5.8 c APe 4.4 d 0.5 c 3.6 c 0.3 d 4.9 d Allf 11.5 a 1.5 a 7.9 a 0.8 a 13.7 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 -1 Non-irrigated Seeding rate, seeds ha 148,000 5.2 c 0.6 c 3.4 b 0.3 c 5.0 c 297,000 8.9 b 1.0 b 5.9 a 0.6 b 8.5 b 445,000 10.7 a 1.3 a 6.7 a 0.8 a 10.4 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 6.7 b 0.7 b 3.9 c 0.4 b 6.0 c MESZ 10.6 a 1.3 a 6.4 a 0.7 a 10.0 a LK 7.3 b 0.8 b 5.3 ab 0.5 b 7.6 bc AP 6.8 b 0.8 b 4.7 bc 0.5 b 7.3 bc All 9.9 a 1.1 a 6.2 a 0.7 a 8.9 ab P>F <0.01 <0.01 0.04 <0.01 0.02 a Total nutrient accumulation calculated as the sum of leaf and stem/petiole (nutrient concentration x dry matter accumulation). b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 63 Table 2.06. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 aboveground nutrient accumulationa, Lansing, MI, 2020. Site Treatment N P K S Zn _____________________ -1_____________________ kg ha g ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 19 bb 1.9 b 12 b 1.2 c 25 b 297,000 31 a 3.1 a 21 a 1.9 b 41 a 445,000 35 a 3.6 a 22 a 2.2 a 43 a P>F <0.01 <0.01 <0.01 <0.01 0.01 Fertilizer Non-fertilized 26 b 2.7 b 17 ab 1.6 b 29 b c MESZ 34 a 3.3 a 20 a 2.2 a 43 a LKd 25 bc 2.6 bc 18 ab 1.5 bc 30 b APe 22 c 2.3 c 15 b 1.4 c 27 b f All 34 a 3.5 a 21 a 2.3 a 53 a P>F <0.01 <0.01 0.06 <0.01 <0.01 Non-irrigated Seeding rate, seeds ha-1 148,000 9c 1.0 c 4.2 c 0.5 c 12 c 297,000 16 b 1.5 b 7.4 b 1.0 b 21 b 445,000 22 a 2.1 a 9.4 a 1.3 a 29 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 15 b 1.6 7.3 0.9 bc 20 b MESZ 20 a 1.8 8.3 1.2 a 27 a LK 15 b 1.5 6.9 0.9 bc 17 b AP 13 b 1.3 5.9 0.7 c 16 b All 16 b 1.4 6.5 1.0 b 25 a P>F 0.03 0.27 0.21 <0.01 <0.01 a Total nutrient accumulation calculated as the sum of leaf and stem/petiole (nutrient concentration x dry matter accumulation). b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 64 Table 2.07. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R8 aboveground nutrient accumulationa, Lansing, MI, 2019. Site Treatment N P K S Zn _______________________ -1_______________________ kg ha g ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 277 bb 25.0 113 18.5 169 297,000 293 a 26.1 109 19.0 167 445,000 306 a 27.0 115 19.7 177 P>F 0.02 0.25 0.55 0.22 0.27 Fertilizer Non-fertilized 287 ab 24.2 d 107 b 18.6 ab 169 c MESZ 301 a 26.1 bc 108 b 19.8 a 176 LKd 277 b 24.4 cd 108 b 17.7 b 164 APe 292 ab 27.2 ab 111 b 19.1 a 167 f All 303 a 28.3 a 127 a 19.8 a 179 P>F 0.06 <0.01 0.01 0.05 0.21 Non-irrigated Seeding rate, seeds ha-1 148,000 231 21.0 73 12.7 162 297,000 233 20.0 73 12.6 160 445,000 236 20.2 69 12.2 151 P>F 0.52 0.26 0.43 0.50 0.16 Fertilizer Non-fertilized 233 20.2 66 b 12.1 c 154 MESZ 234 20.6 76 a 13.1 a 159 LK 227 20.5 75 a 11.9 c 155 AP 237 20.9 69 b 12.4 bc 159 All 236 20.0 71 ab 13.0 a 162 P>F 0.40 0.77 0.04 0.03 0.79 a Total nutrient accumulation calculated as the sum of leaf, stem/petiole, pod, and grain (nutrient concentration x dry matter accumulation). b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 65 Table 2.08. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R8 aboveground nutrient accumulationa, Lansing, MI, 2020. Site Treatment N P K S Zn ____________________ -1____________________ kg ha g ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 360 37 195 26 271 297,000 358 37 210 27 299 445,000 390 41 197 29 307 P>F 0.13 0.15 0.50 0.19 0.39 Fertilizer Non-fertilized 360 bca 37 b 204 27 bc 260 c c MESZ 341 c 36 b 181 25 c 269 bc LKd 406 a 42 a 220 29 a 325 a APe 358 bc 37 b 194 27 bc 292 abc Allf 380 ab 40 ab 205 28 ab 316 ab P>F <0.01 0.10 0.19 0.02 0.10 -1 Non-irrigated Seeding rate, seeds ha 148,000 199 b 19 b 82 b 11 182 b 297,000 246 a 23 a 105 a 12 225 a 445,000 234 a 21 a 90 ab 11 209 ab P>F 0.02 0.03 0.07 0.12 0.06 Fertilizer Non-fertilized 223 21 85 11 b 196 MESZ 251 22 92 13 a 223 LK 225 20 102 11 b 197 AP 224 21 96 11 b 207 All 209 19 87 12 ab 204 P>F 0.20 0.35 0.15 0.05 0.35 a Total nutrient accumulation calculated as the sum of leaf, stem/petiole, pod, and grain (nutrient concentration x dry matter accumulation). b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 66 Table 2.09. Soybean grain yielda as affected by seeding rate and fertilizer application for irrigated and non-irrigated sites, Lansing, MI, 2019-2020. 2019 2020 Treatment Irrigated Non-irrigated Irrigated Non-irrigated _____________________________________ -1_____________________________________ kg ha -1 Seeding rate, seeds ha 148,000 4096 bb 2238 4824 2849 b 297,000 4312 ab 2487 4926 3429 a 445,000 4504 a 2288 5102 3347 a P>F 0.03 0.34 0.66 0.06 Fertilizer Non-fertilized 4306 2400 4768 3209 c MESZ 4272 2395 4933 3540 d LK 4170 2540 5257 3219 e AP 4291 2190 4787 3112 f All 4480 2162 5010 2961 P>F 0.32 0.36 0.48 0.31 a Grain yield adjusted to 135 g kg-1 moisture. b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 67 Table 2.10. Soybean seeding rate and fertilizer application effects on economic returna for irrigated and non-irrigated sites, Lansing, MI, 2019-2020. 2019 2020 Treatment Irrigated Non-irrigated Irrigated Non-irrigated ______________ -1______________ ______________ US$ ha US$ ha-1______________ Seeding rate, seeds ha-1 148,000 1260 664 2087 963 297,000 1277 692 2090 1207 445,000 1286 575 1986 1112 P>F 0.77 0.15 0.31 0.15 Fertilizer Non-fertilized 1275 ab 664 a 2329 a 1533 ab c MESZ 1151 b 549 b 2300 a 1589 a d LK 392 c -131 c 1738 b 698 c e AP 1130 b 455 b 2197 a 1343 b f All 233 d -511 d 1354 c 308 d P>F <0.01 <0.01 <0.01 <0.01 a Economic return calculated as ((soybean grain price x grain yield) – partial budget costs)). b Least square means within each column followed by a common letter are not significantly different at α = 0.10. c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 68 Table 2.11. Break even soybean yielda required to cover the partial budget costs as influenced by fertilizer application, Lansing, MI, 2019-2020. Fertilizer 2019 2020 ________________ -1________________ kg ha Non-fertilized 0 0 b MESZ 354 222 c LK 2625 1647 d AP 440 276 Alle 3431 2153 a Break even soybean yield calculated as partial budget costs ÷ soybean grain price from 2019 ($0.32 kg ha -1) and 2020 ($0.51 kg-1) b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 69 APPENDIX B: CHAPTER 2 DATA COLLECTED BUT NOT INCLUDED IN PUBLICATION Table 2.12. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and >R5-R8 percent of total aboveground dry matter accumulation, Lansing, MI, 2019. Site Treatment V4 R2 R5 >R5-R8 Percent (%) of total aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 2.5 ba 46 66 34 297,000 3.4 a 53 74 26 445,000 3.9 a 53 69 31 P>F 0.03 0.39 0.56 0.56 Fertilizer Non-fertilized 2.9 b 50 b 69 31 MESZb 4.0 a 54 ab 64 36 LKc 2.8 b 46 b 68 32 d AP 2.3 b 46 b 72 28 Alle 4.5 a 61 a 77 23 P>F <0.01 0.04 0.70 0.70 Non-irrigated Seeding rate, seeds ha-1 148,000 2.8 c 45 b 72 34 297,000 4.5 b 54 ab 72 28 445,000 5.5 a 63 a 72 28 P>F <0.01 0.04 0.50 0.50 Fertilizer Non-fertilized 4.0 b 55 71 29 MESZ 4.5 ab 53 71 29 LK 3.7 b 56 70 30 AP 3.7 b 47 67 33 All 5.2 a 59 70 30 P>F 0.01 0.48 0.99 0.99 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 70 Table 2.13. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4, R2, R5, and >R5-R8 percent of total aboveground dry matter accumulation, Lansing, MI, 2020. Site Treatment V4 R2 R5 >R5-R8 Percent (%) of total aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 6.7 ba 15 b 112 -12 297,000 8.5 b 19 b 111 -11 445,000 13.2 a 28 a 148 -48 P>F 0.06 0.03 0.21 0.21 Fertilizer Non-fertilized 8.0 c 18 114 -14 MESZb 12.1 a 25 154 -54 c LK 8.5 bc 17 108 -8 APd 7.8 c 20 113 -13 Alle 10.8 ab 22 132 -32 P>F 0.02 0.28 0.28 0.28 Non-irrigated Seeding rate, seeds ha-1 148,000 3.4 c 14 c 100 0 297,000 5.4 b 18 b 91 9 445,000 8.6 a 23 a 107 -7 P>F <0.01 <0.01 0.61 0.56 Fertilizer Non-fertilized 6.1 a 18 a 102 -2 MESZ 6.7 a 20 a 90 10 LK 5.7 ab 17 ab 122 -22 AP 4.5 b 15 b 83 17 All 5.8 ab 19 a 99 1 P>F 0.08 0.08 0.26 0.24 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 71 Table 2.14. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 dry matter partitioning, Lansing, MI, 2019. Site Treatment Leaves Stems/Petioles Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 77 aa 23 c 297,000 73 b 27 b 445,000 70 c 30 a P>F <0.01 <0.01 Fertilizer Non-fertilized 76 a 24 d b MESZ 70 d 30 a LKc 73 bc 27 bc APd 76 ab 24 cd e All 71 cd 29 ab P>F <0.01 <0.01 Non-irrigated Seeding rate, seeds ha-1 148,000 71 a 29 b 297,000 69 b 31 a 445,000 68 b 32 a P>F 0.06 0.06 Fertilizer Non-fertilized 72 a 28 c MESZ 68 c 32 a LK 71 ab 29 bc AP 69 bc 31 ab All 68 c 32 a P>F 0.01 0.01 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 72 Table 2.15. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated V4 dry matter partitioning, Lansing, MI, 2020. Site Treatment Leaves Stems/Petioles Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 70 a 30 b 297,000 66 b 34 a 445,000 64 b 36 a P>F 0.03 0.03 Fertilizer Non-fertilized 67 33 b MESZ 65 35 LKc 68 32 APd 68 32 e All 65 35 P>F 0.13 0.13 Non-irrigated Seeding rate, seeds ha-1 148,000 69 31 297,000 66 34 445,000 67 33 P>F 0.48 0.48 Fertilizer Non-fertilized 68 32 MESZ 69 31 LK 67 33 AP 66 34 All 66 34 P>F 0.63 0.63 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 73 Table 2.16. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R2 dry matter partitioning, Lansing, MI, 2019. Site Treatment Leaves Stems/Petioles Flowers Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 52 aa 46 2.3 b 297,000 51 ab 47 2.6 b 445,000 50 b 46 3.8 a P>F 0.06 0.20 0.06 Fertilizer Non-fertilized 52 a 45 c 3.3 b MESZ 49 b 48 b 3.1 LKc 53 a 45 c 2.8 APd 52 a 45 c 2.8 e All 48 b 49 a 2.4 P>F <0.01 <0.01 0.50 Non-irrigated Seeding rate, seeds ha-1 148,000 54 a 44 b 2.6 ab 297,000 53 a 45 b 2.8 a 445,000 51 b 47 a 2.2 b P>F 0.03 0.01 0.08 Fertilizer Non-fertilized 52 bc 44 bc 3.0 MESZ 51 c 47 a 2.2 LK 54 a 43 c 2.3 AP 53 ab 44 bc 2.6 All 52 bc 46 ab 2.5 P>F 0.03 0.03 0.24 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 74 Table 2.17. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R2 dry matter partitioning, Lansing, MI, 2020. Site Treatment Leaves Stems/Petioles Flowers Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 59 aa 39 b 1.8 297,000 54 b 44 a 1.6 445,000 53 b 45 a 1.7 P>F <0.01 <0.01 0.69 Fertilizer Non-fertilized 56 a 42 b 1.5 b b MESZ 53 b 45 a 1.8 a LKc 57 a 41 b 1.7 ab APd 58 a 41 b 1.5 b Alle 53 b 45 a 2.0 a P>F <0.01 <0.01 0.02 -1 Non-irrigated Seeding rate, seeds ha 148,000 55 a 43 c 2.2 b 297,000 53 b 44 b 2.4 ab 445,000 52 c 46 a 2.8 a P>F <0.01 <0.01 0.07 Fertilizer Non-fertilized 54 a 43 b 2.4 MESZ 53 b 45 a 2.5 LK 54 a 44 b 2.5 AP 54 a 43 b 2.5 All 52 b 45 a 2.4 P>F <0.01 <0.01 0.99 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 75 Table 2.18. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R5 dry matter partitioning, Lansing, MI, 2019. Site Treatment Leaves Stems/Petioles Flowers/Pods Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 40 aa 50 10 297,000 38 b 50 14 445,000 37 b 51 11 P>F <0.01 0.17 0.44 Fertilizer Non-fertilized 40 a 49 b 12 b MESZ 38 b 51 a 11 LKc 40 a 50 b 12 APd 40 a 50 b 11 e All 37 c 51 a 13 P>F <0.01 <0.01 0.35 Non-irrigated Seeding rate, seeds ha-1 148,000 40 a 46 b 13 297,000 39 ab 47 b 14 445,000 38 b 48 a 14 P>F 0.06 0.04 0.66 Fertilizer Non-fertilized 40 46 14 MESZ 38 47 15 LK 39 47 14 AP 40 47 13 All 39 47 14 P>F 0.15 0.43 0.47 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 76 Table 2.19. Soybean seeding rate and fertilizer application effects on irrigated and non-irrigated R5 dry matter partitioning, Lansing, MI, 2020. Site Treatment Leaves Stems/Petioles Flowers/Pods Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 28 aa 43 b 29 297,000 27 b 45 a 27 445,000 26 b 46 a 27 P>F 0.02 0.08 0.38 Fertilizer Non-fertilized 28 a 45 27 b MESZ 26 c 44 29 LKc 28 ab 46 27 APd 27 bc 45 28 e All 26 c 45 29 P>F 0.02 0.87 0.24 Non-irrigated Seeding rate, seeds ha-1 148,000 27 34 39 297,000 27 35 38 445,000 27 36 37 P>F 0.59 0.52 0.21 Fertilizer Non-fertilized 27 37 36 MESZ 26 35 38 LK 26 35 38 AP 27 34 38 All 28 32 40 P>F 0.19 0.13 0.22 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 77 Table 2.20. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated R8 aboveground dry matter partitioning, Lansing, MI, 2019. Site Treatment Leaves Stems/Petioles Pods Grain Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 13 30 18 aa 38 297,000 15 29 16 b 39 445,000 14 30 16 b 39 P>F 0.19 0.71 <0.01 0.64 Fertilizer Non-fertilized 15 29 17 39 b MESZ 15 31 16 38 LKc 13 29 18 40 APd 16 30 17 38 e All 13 31 17 39 P>F 0.21 0.19 0.18 0.70 Non-irrigated Seeding rate, seeds ha-1 148,000 16 23 b 17 44 297,000 15 25 a 17 43 445,000 15 27 a 15 43 P>F 0.62 0.01 0.12 0.68 Fertilizer Non-fertilized 15 25 bc 17 44 MESZ 14 26 ab 16 44 LK 16 24 c 17 43 AP 16 25 bc 16 43 All 16 27 a 15 42 P>F 0.26 0.04 0.62 0.76 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 78 Table 2.21. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated R8 aboveground dry matter partitioning, Lansing, MI, 2020. Site Treatment Leaves Stems/Petioles Pods Grain Percent (%) of aboveground dry matter Irrigated Seeding rate, seeds ha-1 148,000 14 33 ba 14 39 a 297,000 13 36 b 14 36 a 445,000 16 46 a 13 25 b P>F 0.14 0.01 0.25 0.03 Fertilizer Non-fertilized 14 a 39 14 33 b MESZ 13 bc 38 15 34 LKc 17 a 38 13 31 APd 16 ab 41 13 32 e All 11 c 37 15 35 P>F 0.02 0.81 0.33 0.83 Non-irrigated Seeding rate, seeds ha-1 148,000 12 b 22 c 21 a 45 a 297,000 14 a 25 b 20 b 41 b 445,000 14 a 27 a 19 c 40 b P>F 0.03 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 13 24 20 42 MESZ 13 25 20 42 LK 14 24 20 42 AP 13 24 20 42 All 13 24 20 42 P>F 0.82 0.49 0.91 0.97 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 79 Table 2.22. Percentage of irrigated and non-irrigated season-long soybean nutrient accumulation at V4 as affected by seeding rate and fertilizer, Lansing, MI, 2019. Site Treatment N P K S Zn _________ _________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 2.0 ca 2.5 c 3.2 c 2.0 c 2.0 c 297,000 2.4 b 3.3 b 4.5 b 2.7 b 2.4 b 445,000 3.0 a 4.2 a 5.6 a 3.4 a 3.0 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 1.9 c 2.5 b 3.9 c 2.1 c 1.9 c MESZb 3.1 b 4.6 a 5.1 b 3.4 b 3.1 b LKc 1.9 c 2.4 b 3.7 c 2.1 c 1.9 c APd 1.5 d 1.9 c 3.3 c 1.6 d 1.5 d Alle 3.8 a 5.2 a 6.3 a 4.3 a 3.8 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Non-irrigated Seeding rate, seeds ha-1 148,000 2.4 c 2.8 c 4.7 c 2.8 c 3.1 c 297,000 3.7 b 4.7 b 8.0 b 4.8 b 5.4 b 445,000 4.5 a 6.2 a 9.6 a 6.1 a 6.8 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 2.9 b 3.6 b 6.1 b 3.8 b 4.0 c MESZ 4.5 a 6.1 a 8.7 a 5.5 a 6.5 a LK 3.2 b 3.9 b 6.9 b 4.2 b 4.9 c AP 2.9 b 3.6 b 6.8 b 3.9 b 4.6 c All 4.2 a 5.6 a 8.6 a 5.3 a 5.5 ab P>F <0.01 <0.01 0.04 <0.01 <0.01 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 80 Table 2.23. Percentage of irrigated and non-irrigated season-long soybean nutrient accumulation at V4 as affected by seeding rate and fertilizer, Lansing, MI, 2020. Site Treatment N P K S Zn _________ _________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 5.7 ba 5.5 b 6.5 b 5.1 b 9.3 297,000 8.5 a 8.4 a 9.7 a 7.0 a 13.7 445,000 9.3 a 9.2 a 11.3 a 8.0 a 14.7 P>F 0.03 0.01 0.04 0.04 0.12 Fertilizer Non-fertilized 7.2 b 7.2 b 8.6 bc 6.0 b 10.8 b MESZb 10.0 a 9.6 a 11.4 a 8.9 a 16.4 a LKc 6.0 b 6.0 b 7.8 c 5.3 b 8.9 b APd 6.1 b 6.3 b 7.5 c 5.0 b 9.3 b Alle 9.8 a 9.2 a 10.6 ab 8.3 a 17.5 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Non-irrigated Seeding rate, seeds ha-1 148,000 4.7 c 5.2 c 5.2 c 5.4 c 6.7 c 297,000 7.0 b 7.2 b 7.7 b 8.4 b 9.6 b 445,000 9.9 a 10.3 a 10.9 a 11.9 a 13.3 a P>F <0.01 <0.01 <0.01 <0.01 <0.01 Fertilizer Non-fertilized 7.3 8.0 9.3 9.0 10.5 ab MESZ 10.0 8.2 9.2 9.4 12.0 a LK 7.1 7.8 7.4 8.9 8.6 bc AP 5.9 6.3 6.3 7.0 7.3 c All 7.8 7.6 7.5 8.6 11.0 ab P>F 0.26 0.46 0.21 0.34 <0.01 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 81 Table 2.24. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2019. Site Treatment N P K S Zn ____________ ____________ Percent (%) of V4 accumulation Irrigated Seeding rate, seeds ha-1 148,000 86 76 aa 69 78 a 82 297,000 86 74 ab 69 74 b 82 445,000 85 71 b 66 72 b 81 P>F 0.51 0.05 0.26 0.04 0.61 Fertilizer Non-fertilized 87 a 76 a 69 76 82 MESZb 84 c 71 c 67 74 81 LKc 86 ab 74 ab 67 74 81 APd 86 ab 75 a 69 77 82 Alle 85 b 72 bc 67 74 82 P>F 0.02 0.01 0.32 0.50 0.64 Non-irrigated Seeding rate, seeds ha-1 148,000 83 71 64 76 a 79 297,000 82 70 62 74 ab 77 445,000 83 70 62 72 b 79 P>F 0.84 0.25 0.16 0.04 0.16 Fertilizer Non-fertilized 84 73 a 64 75 79 MESZ 82 69 b 63 73 78 LK 83 72 a 63 75 79 AP 81 69 b 61 72 77 All 82 69 b 62 74 78 P>F 0.13 <0.01 0.29 0.14 0.63 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 82 Table 2.25. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2020. Site Treatment N P K S Zn ____________ ____________ Percent (%) of V4 accumulation Irrigated Seeding rate, seeds ha-1 148,000 81 70 56 78 aa 80 297,000 80 67 52 75 b 78 445,000 80 67 53 73 b 78 P>F 0.49 0.14 0.17 0.07 0.42 Fertilizer Non-fertilized 80 67 54 75 77 MESZb 81 68 54 75 80 LKc 81 68 54 75 79 APd 81 68 55 77 78 Alle 80 67 53 74 79 P>F 0.40 0.97 0.95 0.70 0.30 Non-irrigated Seeding rate, seeds ha-1 148,000 83 70 63 78 80 297,000 82 71 61 78 78 445,000 82 71 63 79 81 P>F 0.69 0.90 0.61 0.89 0.44 Fertilizer Non-fertilized 84 70 63 79 81 MESZ 84 75 66 80 82 LK 82 69 61 78 78 AP 81 69 61 78 77 All 81 71 64 77 80 P>F 0.24 0.37 0.32 0.67 0.13 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 83 Table 2.26. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2019. Site Treatment N P K S Zn ____________ ____________ Percent (%) of V4 accumulation Irrigated Seeding rate, seeds ha-1 148,000 14 24 ba 31 22 b 18 297,000 14 26 ab 31 26 a 18 445,000 15 29 a 34 28 a 19 P>F 0.51 0.05 0.26 0.04 0.61 Fertilizer Non-fertilized 13 c 24 c 31 25 18 MESZb 16 a 29 a 33 26 19 LKc 14 bc 26 bc 33 26 20 APd 14 bc 25 c 31 23 18 Alle 15 b 28 ab 33 26 18 P>F 0.02 0.01 0.32 0.50 0.64 Non-irrigated Seeding rate, seeds ha-1 148,000 17 29 a 36 24 b 21 297,000 18 30 a 38 26 ab 23 445,000 17 30 a 38 28 a 21 P>F 0.84 0.25 0.16 0.04 0.16 Fertilizer Non-fertilized 16 27 b 36 25 21 MESZ 18 31 a 37 27 22 LK 17 28 b 37 25 21 AP 19 31 a 39 28 23 All 18 31 a 38 26 22 P>F 0.13 <0.01 0.29 0.14 0.63 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 84 Table 2.27. Influence of soybean seeding rate and fertilizer application on irrigated and non- irrigated V4 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2020. Site Treatment N P K S Zn ____________ ____________ Percent (%) of V4 accumulation Irrigated Seeding rate, seeds ha-1 148,000 19 30 44 22 aa 20 297,000 20 33 48 25 b 22 445,000 20 33 47 27 b 22 P>F 0.49 0.14 0.17 0.07 0.42 Fertilizer Non-fertilized 20 33 46 25 23 MESZb 19 32 46 25 20 LKc 19 32 46 25 21 APd 19 32 45 23 22 Alle 20 33 47 26 21 P>F 0.40 0.97 0.95 0.70 0.30 Non-irrigated Seeding rate, seeds ha-1 148,000 17 30 35 22 20 297,000 18 29 39 22 22 445,000 18 29 35 21 19 P>F 0.69 0.90 0.61 0.89 0.44 Fertilizer Non-fertilized 16 30 35 21 19 MESZ 16 25 34 20 18 LK 18 31 39 22 22 AP 19 31 39 22 23 All 19 29 36 23 20 P>F 0.24 0.37 0.32 0.67 0.13 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 85 Table 2.28. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2019. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 7.0 5.9 4.0 7.9 14 297,000 7.3 6.5 4.8 8.9 14 445,000 7.1 6.3 3.8 8.4 13 P>F 0.91 0.76 0.19 0.50 0.78 Fertilizer Non-fertilized 7.0 6.1 4.3 8.2 13 MESZa 7.9 7.2 4.8 9.4 15 LKb 6.6 5.4 3.9 7.7 12 APc 7.5 6.7 4.6 8.7 14 Alld 6.8 5.8 3.7 7.8 13 P>F 0.58 0.37 0.31 0.45 0.33 Non-irrigated Seeding rate, seeds ha-1 148,000 6.1 5.9 3.2 7.8 16 297,000 6.5 6.0 3.5 8.1 12 445,000 6.4 5.8 3.0 8.2 12 P>F 0.70 0.96 0.72 0.86 0.20 Fertilizer Non-fertilized 5.7 5.4 2.8 7.2 13 MESZ 6.1 5.5 3.1 7.7 13 LK 6.4 5.6 3.3 8.0 14 AP 7.0 7.1 3.8 9.0 15 All 6.4 6.0 3.1 8.2 14 P>F 0.49 0.22 0.42 0.28 0.40 a MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). b LK: liquid potassium (0-0-28 N-P-K). c AP: ammonium polyphosphate (10-34-0 N-P-K). d All: combination of MESZ, LK, and AP fertilizer applications. 86 Table 2.29. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the leaves, Lansing, MI, 2020. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 7.4 6.9 5.6 1.1 16 297,000 8.9 7.7 5.8 1.2 21 445,000 8.2 8.2 5.4 1.4 19 P>F 0.59 0.70 0.89 0.40 0.34 Fertilizer Non-fertilized 8.6 8.0 6.3 1.3 17 MESZb 7.2 6.6 5.6 1.2 15 LKc 8.4 8.0 6.4 1.2 21 APd 10.0 9.3 6.5 1.5 22 Alle 6.7 6.1 4.3 1.0 17 P>F 0.18 0.22 0.18 0.28 0.27 Non-irrigated Seeding rate, seeds ha-1 148,000 7.4 6.1 2.8 1.2 23 297,000 8.1 7.0 3.3 1.4 24 445,000 8.1 7.2 3.4 1.4 24 P>F 0.57 0.40 0.19 0.42 0.73 Fertilizer Non-fertilized 7.4 6.3 2.5 ba 1.3 22 MESZ 7.1 6.1 2.7 b 1.4 21 LK 7.6 6.5 3.8 a 1.1 24 AP 7.8 6.8 3.0 b 1.3 24 All 9.5 8.2 3.9 a 1.6 27 P>F 0.18 0.28 <0.01 0.11 0.15 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 87 Table 2.30. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2019. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 5.1 6.3 12.8 12 4.8 297,000 4.2 4.9 10.8 11 4.2 445,000 4.7 4.6 11.2 11 4.3 P>F 0.18 0.14 0.40 0.55 0.26 Fertilizer Non-fertilized 3.9 ba 3.7 c 10.2 b 11 bc 3.7 b MESZb 5.3 a 5.8 ab 10.9 b 13 a 5.1 a LKc 4.0 b 4.3 bc 11.3 b 10 c 4.0 b APd 4.7 ab 5.8 ab 11.2 b 11 bc 4.1 b Alle 5.4 a 6.6 a 14.5 a 12 ab 5.3 a P>F 0.01 0.02 0.09 0.04 0.03 Non-irrigated Seeding rate, seeds ha-1 148,000 4.0 3.5 4.2 5.9 3.5 297,000 4.0 3.5 4.7 6.3 4.4 445,000 4.4 3.9 4.5 5.9 4.4 P>F 0.22 0.65 0.81 0.58 0.17 Fertilizer Non-fertilized 3.3 c 3.5 3.1 b 4.9 b 3.8 MESZ 5.1 a 4.2 5.7 a 7.5 a 4.5 LK 3.6 bc 3.2 5.6 a 4.7 b 3.6 AP 3.8 bc 3.8 3.6 b 5.4 b 3.9 All 4.2 ab 3.5 4.3 ab 7.0 a 4.6 P>F 0.03 0.58 0.06 <0.01 0.30 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 88 Table 2.31. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the stems/petioles, Lansing, MI, 2020. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 6.0 ba 9.1 b 19 19 b 6.2 297,000 8.0 ab 11.4 ab 23 24 a 8.1 445,000 9.8 a 13.2 a 22 23 a 8.9 P>F 0.04 0.09 0.24 0.01 0.12 Fertilizer Non-fertilized 8.2 11.5 22 23 ab 8.3 MESZb 7.3 10.6 19 20 c 8.2 LKc 7.6 10.2 22 21 bc 6.9 APd 9.2 12.9 22 24 a 8.2 Alle 7.6 11.0 20 22 abc 7.3 P>F 0.37 0.50 0.69 0.09 0.50 Non-irrigated Seeding rate, seeds ha-1 148,000 4.8 5.9 6.5 6.9 5.1 297,000 5.1 6.3 6.8 7.2 5.4 445,000 5.0 5.8 6.5 6.6 5.2 P>F 0.80 0.80 0.61 0.85 0.72 Fertilizer Non-fertilized 4.8 6.4 4.8 c 6.2 ab 4.9 MESZ 4.9 5.8 5.3 bc 7.7 a 5.0 LK 4.8 5.6 8.4 a 5.4 b 5.0 AP 5.1 6.6 6.6 ab 6.4 ab 5.8 All 5.3 5.7 6.9 a 8.8 a 5.5 P>F 0.95 0.85 <0.01 0.05 0.41 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 89 Table 2.32. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the pods, Lansing, MI, 2019. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 4.8 4.2 21 8.2 6.6 297,000 4.3 4.1 19 7.7 5.7 445,000 4.1 3.6 19 7.4 5.4 P>F 0.28 0.53 0.13 0.37 0.15 Fertilizer Non-fertilized 4.1 3.6 18 7.6 5.9 MESZb 4.6 4.0 19 7.9 5.8 LKc 4.0 3.6 20 7.2 5.8 APd 4.5 4.4 19 7.8 5.9 Alle 4.7 4.2 22 8.2 6.3 P>F 0.53 0.65 0.18 0.70 0.96 Non-irrigated Seeding rate, seeds ha-1 148,000 3.4 3.3 12.1 4.3 4.2 297,000 4.3 3.6 11.6 4.2 4.4 445,000 2.8 2.4 9.2 3.2 3.2 P>F 0.38 0.47 0.11 0.40 0.39 Fertilizer Non-fertilized 3.4 3.0 8.6 ca 3.8 3.9 MESZ 3.4 3.5 12.6 ab 4.4 4.4 LK 3.3 2.7 13.7 a 3.6 3.7 AP 3.8 3.2 9.8 c 3.9 4.0 All 3.6 3.0 10.2 bc 3.8 3.9 P>F 0.93 0.84 0.02 0.88 0.88 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 90 Table 2.33. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the pods, Lansing, MI, 2020. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 4.5 ba 5.4 b 18 6.2 b 5.5 b 297,000 5.2 ab 6.6 a 22 7.6 a 6.4 ab 445,000 5.8 a 7.3 a 18 6.7 ab 7.3 a P>F 0.06 0.05 0.11 0.07 0.05 Fertilizer Non-fertilized 5.6 7.1 21 7.2 6.9 MESZb 4.9 6.1 19 7.0 6.7 LKc 4.7 5.8 17 6.1 5.8 APd 5.4 6.8 20 7.2 6.5 Alle 5.3 6.3 19 6.7 6.3 P>F 0.51 0.36 0.48 0.39 0.49 Non-irrigated Seeding rate, seeds ha-1 148,000 6.8 6.8 24 a 7.7 a 7.5 a 297,000 6.7 6.4 24 a 7.7 a 7.3 a 445,000 5.4 5.1 19 b 5.8 b 5.5 b P>F 0.21 0.15 0.10 0.08 0.09 Fertilizer Non-fertilized 6.1 6.0 19 b 6.7 6.6 MESZ 5.7 5.5 19 b 6.2 6.5 LK 6.0 5.9 24 a 6.7 6.2 AP 6.8 6.6 25 a 8.2 7.7 All 7.0 6.6 24 a 7.5 6.8 P>F 0.61 0.74 0.04 0.26 0.60 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 91 Table 2.34. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the grain, Lansing, MI, 2019. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 84 84 62 72 75 297,000 84 85 66 73 76 445,000 84 86 66 73 78 P>F 0.66 0.51 0.26 0.84 0.51 Fertilizer Non-fertilized 85 87 66 74 78 MESZb 82 83 65 70 74 LKc 86 87 65 76 78 APd 83 83 66 73 76 Alle 83 83 60 72 76 P>F 0.21 0.14 0.26 0.16 0.43 Non-irrigated Seeding rate, seeds ha-1 148,000 87 87 82 83 77 297,000 85 87 80 81 78 445,000 86 88 83 83 80 P>F 0.44 0.74 0.28 0.71 0.21 Fertilizer Non-fertilized 88 88 88 aa 85 a 80 MESZ 86 87 79 cd 81 c 79 LK 87 88 78 d 84 ab 78 AP 85 86 83 b 82 bc 77 All 86 88 82 bc 81 bc 78 P>F 0.34 0.38 <0.01 0.10 0.69 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 92 Table 2.35. Influence of seeding rate and fertilizer application on irrigated and non-irrigated R8 N, P, K, S, and Zn partitioning to the grain, Lansing, MI, 2020. Site Treatment N P K S Zn ___________ ___________ Percent (%) of total accumulation Irrigated Seeding rate, seeds ha-1 148,000 82 79 57 67 aa 72 297,000 78 74 49 59 b 65 445,000 76 71 55 61 b 65 P>F 0.16 0.13 0.13 0.04 0.13 Fertilizer Non-fertilized 78 74 51 61 68 MESZb 81 77 57 65 70 LKc 79 76 54 64 66 APd 75 71 51 58 63 Alle 81 77 56 64 70 P>F 0.14 0.30 0.44 0.14 0.54 Non-irrigated Seeding rate, seeds ha-1 148,000 81 81 67 76 65 297,000 78 80 67 75 64 445,000 81 82 71 76 65 P>F 0.39 0.68 0.38 0.72 0.84 Fertilizer Non-fertilized 82 81 74 a 77 66 MESZ 82 83 73 a 76 67 LK 81 82 64 b 77 64 AP 78 80 67 b 75 63 All 78 79 65 b 72 61 P>F 0.30 0.71 0.02 0.40 0.32 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 93 Table 2.36. Irrigated and non-irrigated soybean grain nutrient concentration at physiological maturity (R8) as affected by seeding rate and fertilizer application, Lansing, MI, 2019. Site Treatment N P K S Zn ______________________ -1______________________ g kg mg kg-1 -1 Irrigated Seeding rate, seeds ha 148,000 65 ba 5.9 19 3.1 b 35 297,000 66 a 5.9 19 3.2 a 34 445,000 66 a 5.9 19 3.2 a 35 P>F 0.05 0.89 0.42 0.02 0.41 Fertilizer Non-fertilized 65 b 5.6 c 19 b 3.1 b 35 b MESZ 67 a 5.9 bc 19 b 3.2 a 35 LKc 66 b 5.8 c 19 b 3.2 a 35 APd 65 b 6.0 ab 19 b 3.1 b 34 e All 65 b 6.1 a 20 a 3.2 a 35 P>F 0.01 <0.01 <0.01 <0.01 0.58 Non-irrigated Seeding rate, seeds ha-1 148,000 63 5.7 18 3.1 a 38 297,000 64 5.6 18 3.0 b 39 445,000 64 5.5 18 2.9 b 38 P>F 0.43 0.48 0.47 <0.01 0.70 Fertilizer Non-fertilized 64 ab 5.5 18 3.0 38 MESZ 63 b 5.5 18 3.0 38 LK 62 c 5.6 18 2.9 38 AP 64 ab 5.7 18 3.0 39 All 65 a 5.6 18 3.0 39 P>F <0.01 0.81 0.17 0.35 0.97 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 94 Table 2.37. Irrigated and non-irrigated soybean grain nutrient concentration at physiological maturity (R8) as affected by seeding rate and fertilizer application, Lansing, MI, 2020. Site Treatment N P K S Zn ______________________ -1______________________ g kg mg kg-1 -1 Irrigated Seeding rate, seeds ha 148,000 57 5.6 21 3.3 37 297,000 58 5.7 21 3.4 39 445,000 58 5.7 21 3.4 38 P>F 0.13 0.55 0.80 0.13 0.34 Fertilizer Non-fertilized 58 5.6 21 3.4 36 b MESZ 58 5.7 21 3.4 38 LKc 58 5.7 21 3.4 38 APd 58 5.6 21 3.3 39 e All 56 5.7 21 3.4 40 P>F 0.48 0.55 0.11 0.19 0.17 Non-irrigated Seeding rate, seeds ha-1 148,000 56 ba 5.4 19 2.8 42 297,000 57 ab 5.3 19 2.7 41 445,000 58 a 5.2 19 2.7 42 P>F 0.07 0.28 0.22 0.18 0.35 Fertilizer Non-fertilized 57 b 5.3 19 2.6 c 41 c MESZ 58 a 5.2 19 2.8 b 42 b LK 57 b 5.2 20 2.6 c 39 d AP 57 b 5.4 19 2.6 c 41 c All 57 b 5.3 19 3.0 a 44 a P>F 0.02 0.21 0.11 <0.01 <0.01 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 95 Table 2.38. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated nodule count, stem diameter, and pod count, Lansing, MI, 2019. Site Treatment Nodule count Stem diameter Pod count -1 _______ _______ nodules plant mm pods ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 69 8.6 aa 13333362 297,000 64 6.3 b 11917302 445,000 55 5.5 c 13554528 P>F 0.16 <0.01 0.33 Fertilizer Non-fertilized 58 6.4 c 12273464 b b MESZ 63 7.3 b 13077904 ab LKc 61 6.2 c 11879669 b APd 67 6.1 c 12441330 b e All 64 8.0 a 15002954 a P>F 0.76 <0.01 0.07 -1 Non-irrigated Seeding rate, seeds ha 148,000 30 7.0 a 8501695 297,000 30 5.3 b 9278077 445,000 28 4.6 c 8349424 P>F 0.79 <0.01 0.34 Fertilizer Non-fertilized 26 5.2 b 8231339 MESZ 30 6.1 a 9322920 LK 27 5.3 b 8551868 AP 33 5.4 b 8478381 All 31 6.1 a 8964153 P>F 0.48 <0.01 0.68 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 96 Table 2.39. Impact of soybean seeding rate and fertilizer application on irrigated and non- irrigated nodule count, stem diameter, and pod count, Lansing, MI, 2020. Site Treatment Nodule count Stem diameter Pod count nodules plant-1 _______mm_______ pods ha-1 -1 Irrigated Seeding rate, seeds ha 148,000 107 12.0 aa 10824875 297,000 83 9.2 b 12330637 445,000 70 7.4 c 10329499 P>F 0.12 <0.01 0.42 Fertilizer Non-fertilized 88 9.1 12396055 b MESZ 85 10.2 10127732 LKc 91 9.3 11032240 APd 87 9.5 10759793 e All 82 9.6 11492532 P>F 0.75 0.20 0.65 -1 Non-irrigated Seeding rate, seeds ha 148,000 35 10.5 a 11121083 297,000 32 7.8 b 13813216 445,000 29 5.9 c 11506068 P>F 0.31 <0.01 0.13 Fertilizer Non-fertilized 33 7.4 c 11553662 MESZ 35 8.3 b 11823999 LK 28 7.8 b 12514562 AP 31 7.7 bc 13241071 All 34 9.1 a 11600651 P>F 0.48 <0.01 0.80 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). c LK: liquid potassium (0-0-28 N-P-K). d AP: ammonium polyphosphate (10-34-0 N-P-K). e All: combination of MESZ, LK, and AP fertilizer applications. 97 Table 2.40. Irrigated white mold incidence, white mold severity, and lodging as influenced by soybean seeding rate and fertilizer application, Lansing, MI, 2020. Treatment Incidence Severitya Lodgingb ________ ________ _______ % 0-3_______ _______0-5_______ Seeding rate, seeds ha-1 148,000 20 aa 0.6 a 1.6 a 297,000 21 a 0.8 a 2.1 a 445,000 22 a 0.8 a 2.8 a P>F 0.37 0.26 0.42 Fertilizer Non-fertilized 23 a 0.7 a 1.6 a c MESZ 20 a 1.1 a 2.3 a d LK 22 a 0.7 a 2.5 a e AP 20 a 0.6 a 2.4 a f All 20 a 0.8 a 2.0 a P>F 0.31 0.12 0.95 a White mold severity rated using a scale of 0 = no symptoms and 3 = lesions on main stem resulting in poor pod fill or plant death. b Lodging rated using a scale of 0-5 where 0 = no lodging and 5 = plants completely lodged c MESZ: MicroEssential SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). d LK: liquid potassium (0-0-28 N-P-K). e AP: ammonium polyphosphate (10-34-0 N-P-K). f All: combination of MESZ, LK, and AP fertilizer applications. 98 LITERATURE CITED 99 LITERATURE CITED AOAC. (1995a). Protein (crude) in animal feed. Dumas method (968.06). Official methods of analysis (15th ed.). Washington, DC: Association of Official Agricultural Chemists. AOAC. (1995b). Metals and other elements in plants and pet foods. Inductively coupled plasma spectroscopic method (985.01). Official methods of analysis (15th ed.). Washington, DC: Association of Official Agricultural Chemists. Alessi, J., and Power, J.F. (1982). Effects of plant and row spacing on dryland soybean yield and water-use efficiency. Agronomy Journal, 74:851-854. Andriani, J.M., Andrade, F.H., Suero, E., and Dardanelli, J. (1991). Water deficit during reproductive growth of soybeans. I. Their effects on dry matter accumulation, seed yield and its components. Agronomie 11:737–746. Ball, R.A., Purcell, L.C. and Vories, E.D. (2000). Short-Season Soybean Yield Compensation in Response to Population and Water Regime. Crop Science, 40: 1070-1078. Bender, R.R., Haegele, J.W. and Below, F.E. (2015). Nutrient Uptake, Partitioning, and Remobilization in Modern Soybean Varieties. Agronomy Journal, 107: 563-573. Bergersen, F.J. (1958). The bacterial component of soybean root nodules; changes in respiratory activity, cell dry weight and nucleic acid content with increasing nodule age. J. Gen. Microbiol. 19: 312- 323. Bluck, G.M., Lindsey, L.E., Dorrance, A.E., and Metzger, J.D. (2015). Soybean Yield Response to Rhizobia Inoculant, Gypsum, Manganese Fertilizer, Insecticide, and Fungicide. Agronomy Journal, 107: 1757-1765. Boem, F. H. G., Prystupa, P., & Ferraris, G. (2007). Seed number and yield determination in sulfur deficient soybean crops. Journal of Plant Nutrition, 30, 93– 104. Carpenter, A.C., and Board, J.E. (1997a). Branch yield components controlling soybean yield stability across plant populations. Crop Science, 37:885-891. Carpenter, A.C., and Board, J.E. (1997b). Growth dynamic factors controlling soybean yield stability across plant populations. Crop Science, 37:1520-1526. Ciampitti, I.A. and Salvagiotti, F. (2018). New Insights into Soybean Biological Nitrogen Fixation. Agronomy Journal, 110: 1185-1196. 100 Chen, Y., and Wang, D. (2005). Two convenient methods to evaluate soybean for resistance to Sclerotinia sclerotiorum. Plant Dis. 89, 1268–1272. Chen, G., and Wiatrak, P. (2011). Seeding rate effects on soybean height, yield, and economic return. Agronomy Journal., 103:1301-1307. Chien, S.H., Prochnow, L.I., and Cantarella. H. (2009). Recent developments of fertilizer production and use to increase nutrient efficiency and minimize environmental impacts. Adv. Agron. 102:261–316. Chien, S.H., Teixeira, L.A., Cantarella, H., Rehm, G.W., Grant, C.A. and Gearhart, M.M. (2016). Agronomic Effectiveness of Granular Nitrogen/Phosphorus Fertilizers Containing Elemental Sulfur with and without Ammonium Sulfate: A Review. Agronomy Journal, 108: 1203-1213. Combs, S. M., Denning, J. L., & Frank, K. D. (2015). Sulfate-sulfur. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the North Central Region (pp. 81– 86). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Combs, S. M., & Nathan, M. V. (2015). Soil organic matter. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 121– 126). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Cox, W.J., Cherney, J.H., and Shields, E. (2010). Soybeans compensate at low seeding rates but not at high thinning rates. Agronomy Journal, 102:1238-1243. Culman, S., Fulford, A., Camberato, J., and Steinke, K. (2020). Tri-State Fertilizer Recommendations. Bulletin 974. College of Food, Agricultural, and Environmental Sciences. Columbus, OH: The Ohio State University. De Bruin, J.L. and Pedersen, P. (2009). Growth, Yield, and Yield Component Changes among Old and New Soybean Cultivars. Agronomy Journal, 101: 124-130. Degryse, F., Baird, R., Andelkovic, I., and McLaughlin, M. (2021). Long-term fate of fertilizer sulfate- and elemental S in co-granulated fertilizers. Nutr Cycl Agroecosyst, 120, 31–48. Duncan, W. G. (1986). Planting patterns and soybean yields. Crop Science, 26, 584– 588. Egli, D. B. (1988a). Alterations in plant growth and dry matter distribution in soybean. Agronomy Journal, 80, 86– 90. Egli, D.B. (1988b). Plant density and soybean yield. Crop Science, 28:977-98. 101 Engels, C., E. Kirkby, and P. White. (2012). Mineral nutrition, yield, and source-sink relationships. In: P. Marschner, editor, Marschner's mineral nutrition of higher plants. Elsevier, London. p. 85–133. Fehr, W. R., & Caviness, C. E. (1977). Stages of soybean development. Special Report 80. Ames: Iowa Agricultural Home Economics Experiment Station., Iowa State University. Frank, K., Beegle, D., & Denning, J. (2015). Phosphorus. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 61– 66). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Freeborn, J.R., Holshouser, D.L., Alley, M.M., Powell, N.L. and Orcutt, D.M. (2001). Soybean Yield Response to Reproductive Stage Soil-Applied Nitrogen and Foliar-Applied Boron. Agronomy Journal, 93: 1200-1209. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2017a). Dry matter and nitrogen uptake, partitioning, and removal across a wide range of soybean seed yield levels. Crop Science, 57:2170-2182. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2017b). Phosphorus and potassium uptake, partitioning, and removal across a wide range of soybean seed yield levels. Crop Science, 57:2193-2204. Gaspar, A.P., Laboski, C.A.M., Naeve, S.L., and Conley, S.P. (2018). Secondary and micronutrient uptake, partitioning, and removal across a wide range of soybean seed yield levels. Agronomy Journal, 110:1328-1338. Goyal, D., Franzen, D.W., Cihacek, L.J. and Chatterjee, A. (2021). Corn response to incremental applications of sulfate-sulfur. Agronomy Journal. Accepted Author Manuscript. Grau C.R. (1988). Sclerotinia stem rot of soybean. p. 56–66. In T.D. Wyllie and D.H. Scott (eds.) Soybean diseases of the north central region. Am. Phytopath. Soc., St. Paul, MN. Grau, Craig R., Adee, Eric A., and Oplinger, Edward S. (1994). An Integrated Approach to Control Sclerotinia Stem Rot (White Mold) in Soybean. Proceedings of the Integrated Crop Management Conference. 25. Hamman, B., Egli, D.B. and Koning, G. (2002). Seed Vigor, Soilborne Pathogens, Preemergent Growth, and Soybean Seedling Emergence. Crop Science, 42: 451-457. Hankinson, M.W., Lindsey, L.E, and Culman, S.W. (2015). Effect of planting date and starter fertilizer on soybean grain yield. Crop, Forage & Turfgrass Management, 1:2015-0178. 102 Haq, M.U. and Mallarino, A.P. (2000), Foliar Fertilization of Soybean at Early Vegetative Stages. Agronomy Journal, 90: 763-769. Harder, D.B., Sprague, C.L., and Renner, K.A. (2007). Effect of soybean row width and population on weeds, crop yield, and economic return. Weed Technology, 21:744-752. Hardy, R.W.F., Burns, R.C., Hebert, R.R., Holsten, R.D., and Jackson, E.K. (1971). Biological nitrogen fixation: A key to world protein. p. 561- 590. In T.A. Iie and E.G. Mulder (ed.) Biological nitrogen fixation in natural and agricultural habitats. Plant Soil Spec. Martinus Nijhoff, The Hague, the Netherlands. Havlin, J. L., Tisdale, S. L., Beaton, J. D., and Nelson, W. L. (2014). Soil fertility and fertilizers: An introduction to nutrient management (8th ed.). Upper Saddle River, NJ: Pearson Prentice Hall. Hicks, D. R., Lueschen, W. E., & Ford, J. H. (1990). Effect of stand density and thinning on soybean. Journal of Production Agriculture, 3, 587– 590. Hitsuda, K., Toriyama, K., Subbarao, G.V. and Ito, O. (2008). Sulfur Management for Soybean Production. In J. Jez (Ed.), Sulfur: A Missing Link between Soils, Crops, and Nutrition, (pp. 117-142), Madison, WI: ASA, CSSA, and SSSA. Hu, M. and Wiatrak, P. (2012). Effect of Planting Date on Soybean Growth, Yield, and Grain Quality: Review. Agronomy Journal, 104: 785-790. Kaiser, D.E., and Kim, K. (2013). Soybean response to sulfur fertilizer applied as a broadcast or starter using replicated strip trials. Agronomy Journal, 105:1189-1198. Lee, C.D., Egli, D.B., and TeKrony, D.M. (2008). Soybean response to plant population at early and late planting dates in the Mid-South. Agronomy Journal, 100:971-976. Marcelis, L.F.M. (1996). Sink strength as a determinant of dry matter partitioning in the whole plant. J. Exp. Bot. 47:1281–1291. McGrath, S.P., and Zhao, F.J. (1995). A risk assessment of sulphur deficiency in cereals using soil and atmospheric deposition data. Soil Use Manage., 11:110–114. Mueller, D.S., Bradley, C., Chilvers, M., Esker, P., Malvick, D., Peltier, A., Sisson, A., Wise, K. (2015). White mold: Soybean Disease Management. Crop Protection Network, 1005. National Oceanic and Atmospheric Administration. (2019). National climatic data center. NOAA. Retrieved from http://www.ncdc.noaa.gov Osborne, S.L. and Riedell, W.E. (2006), Starter Nitrogen Fertilizer Impact on Soybean Yield and Quality in the Northern Great Plains. Agronomy Journal, 98: 1569-1574. 103 Peters, J. B., Nathan, M. V., & Labowski, C. A. M. (2015). pH and lime requirement. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 41– 47). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Purucker, T, Steinke, K. (2020). Soybean seeding rate and fertilizer effects on growth, partitioning, and yield. Agronomy Journal, 112: 2288– 2301. Quinn, D. and Steinke, K. (2019). Comparing High‐ and Low‐Input Management on Soybean Yield and Profitability in Michigan. Crop, Forage & Turfgrass Management, 5: 1-8 190029. Ray, J.D., Heatherly, L.G. and Fritschi, F.B. (2006). Influence of Large Amounts of Nitrogen on Nonirrigated and Irrigated Soybean. Crop Science, 46: 52-60. Rincker, K., Nelson, R., Specht, J., Sleper, D., Cary, T., Cianzio, S.R., Casteel, S., Conley, S., Chen, P., Davis, V., Fox, C., Graef, G., Godsey, C., Holshouser, D., Jiang, G.-L., Kantartzi, S.K., Kenworthy, W., Lee, C., Mian, R., McHale, L., Naeve, S., Orf, J., Poysa, V., Schapaugh, W., Shannon, G., Uniatowski, R., Wang, D. and Diers, B. (2014). Genetic Improvement of U.S. Soybean in Maturity Groups II, III, and IV. Crop Science, 54: 1419-1432. Rowntree, S.C., Suhre, J.J., Weidenbenner, N.H., Wilson, E.W., Davis, V.M., Naeve, S.L., Casteel, S.N., Diers, B.W., Esker, P.D., Specht, J.E. and Conley, S.P. (2013). Genetic Gain × Management Interactions in Soybean: I. Planting Date. Crop Science, 53: 1128- 1138. Rutan, J. and Steinke, K. (2018). Pre-Plant and In-Season Nitrogen Combinations for the Northern Corn Belt. Agronomy Journal, 110: 2059-2069. Salvagiotti, F., Specht, J.E., Cassman, K.G., Walters, D.T., Weiss, A. and Dobermann, A. (2009). Growth and Nitrogen Fixation in High-Yielding Soybean: Impact of Nitrogen Fertilization. Agronomy Journal, 101: 958-970. Salvagiotti, F., Cassman, K., Specht, J., Walters, D., Weiss, A., and Dobermann, A. (2008). Nitrogen uptake, fixation and response to fertilizer N in soybeans: A review, Field Crops Res., 108, 1–13. SAS Institute. (2012). The SAS System for windows. Version 9.4. Cary, NC: SAS Institute. Southworth, J., Randolph, J.C., Habeck, M., Doering, O.C., Pfeifer, R.A., Rao, D.G., Johnston, J.J. (2000). Consequences of future climate change and changing climate variability on maize yields in the midwestern United States. Agric. Ecosyst. Environ., 82 (1–3) (2000), pp. 139-158. 104 Sorensen, R.C. and Penas, E.J. (1978). Nitrogen Fertilization of Soybeans1. Agronomy Journal, 70: 213-216. Specht, J.E., Hume, D.J. and Kumudini, S.V. (1999). Soybean Yield Potential—A Genetic and Physiological Perspective. Crop Science, 39: 1560-1570. Suhre, J.J., Weidenbenner, N.H., Rowntree, S.C., Wilson, E.W., Naeve, S.L., Conley, S.P., Casteel, S.N., Diers, B.W., Esker, P.D., Specht, J.E. and Davis, V.M. (2014). Soybean Yield Partitioning Changes Revealed by Genetic Gain and Seeding Rate Interactions. Agronomy Journal, 106: 1631-1642. Sutradhar, A.K., Kaiser, D.E., and Behnken, L.M. (2017). Soybean response to broadcast application of boron, chlorine, manganese, and zinc. Agronomy Journal, 109:1048-1059. Stein, D. (2019). 2019 Custom machine and work rate estimates. East Lansing, MI: Michigan State University Extension. Retrieved from https://www.canr.msu.edu/isabella/uploads/files/2019%20MSU%20Custom%20Wo rk%20Rates.pdf Tamagno, S., Sadras, V. O., Haegele, J. W., Armstrong, P. R., & Ciampitti, I.A. (2018). Interplay between nitrogen and biological nitrogen fixation in soybean: Implications on seed yield and biomass allocation. Scientific Reports, 8, 17502. Taylor, R.S., Weaver, D.B., Wood, C.W., and van Santen, E. (2005). Nitrogen Application Increases Yield and Early Dry Matter Accumulation in Late‐Planted Soybean. Crop Science, 45: 854-858. Touchton, J.T. and Rickerl, D.H. (1986). Soybean Growth and Yield Responses to Starter Fertilizers. Soil Science Society of America Journal, 50: 234-237. Torrion, J.A., Setiyono, T.D., Graef, G.L., Cassman, K.G., Irmak, S. and Specht, J.E. (2014), Soybean Irrigation Management: Agronomic Impacts of Deferred, Deficit, and Full- Season Strategies. Crop Science, 54: 2782-2795. USDA National Agricultural Statistics Service. (2021). USDA-NASS agricultural statistics 2021. USDA-NASS. http://www.nass.usda.gov Vitosh, M.L., Johnson, J.W., and Mengel, D.B. (1995). Tri-State fertilizer recommendations for corn, soybeans, wheat and alfalfa. E2567. East Lansing, MI: Michigan State University Extension. Walker, E. R., Mengistu, A., Bellaloui, N., Koger, C. H., Roberts, R. K., & Larson, J. A. (2010). Plant population and row-spacing effects on maturity group III soybean. Agronomy Journal, 102, 821– 826. 105 Warncke, D., & Brown, J. R. (2015). Potassium and other basic cations. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the North Central Region (pp. 71– 73). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Warncke, D., Dahl, J., and Jacobs, L. (2009). Nutrient recommendations for field crops in Michigan. Bulletin E2904, East Lansing, MI: Michigan State University Extension. Warncke, D., Robertson, L. S., & Mokma, D. (1980). Cation exchange capacity determination for acid and calcareous soils. In Agronomy abstracts (p. 147). Madison, WI: ASA. Whitney, D. A. (2015). Micronutrients: Zinc, iron, manganese and copper. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 91– 94). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station: Wingeyer, A.B., Echeverría, H. and Rozas, H.S. (2014). Growth and Yield of Irrigated and Rainfed Soybean with Late Nitrogen Fertilization. Agronomy Journal, 106: 567-576. World Health Organization (2002). Quantifying selected major risks to health. In The World Health Report 2002. Geneva: WHO. 106 CHAPTER 3 NITROGEN AND SULFUR RESPONSES OF DRY BEAN IN MICHIGAN Abstract Greater dry bean (Phaseolus vulgaris L.) yield and a potential decrease in soil sulfur (S) supply has practitioners questioning whether nitrogen (N) and sulfur fertilizer response in dry bean has increased. Three multi-year trials were established in Michigan to evaluate nitrogen rate, sulfur rate, and sulfur source on dry bean growth and grain yield. Four dry bean varieties responded similarly to N rate, S rate, and S source across all site-years. Compared to applying no N, ≥ 60 lb N/acre increased dry matter accumulation up to 46 and 54%, but grain yield was not significantly influenced by N rate. S application did not significantly increase grain yield regardless of rate or source as implied by lack of S deficiency symptoms, adequate S concentration in the uppermost trifoliate, and SOM (soil organic matter) levels between 2.4 and 2.6%. The data suggest the likelihood of a grain yield response from supplemental S application may be dependent on site-specific factors and soil properties. Although N application did not benefit dry bean grain yield, the influence unpredictable weather has on N supply and demand combined with a short growing season (i.e., 85 to 100 d) may justify to some extent N application to protect yield potential. However, excess N applications can reduce nodulation and increase risk for disease and N loss to the environment. Introduction Michigan ranks second in total U.S. dry bean production (6,033,000 cwt) generating more than US$185 million (USDA NASS, 2020) with black bean, navy bean, and small red bean 107 the top major market classes (USDA NASS, 2020). Production acres are focused in the northeastern Saginaw Valley region where loam and clay soils dominate and growers typically plant anywhere from 85 to 100 d maturity beans during June with harvest in September. From 2000 to 2020, average grain yield of black, navy, and small red increased by 51, 59, and 67%, respectively (USDA NASS, 2020). Increases in grain yield potential may partially be due to the genetic advancement of dry bean varieties (e.g., disease resistance and stress tolerance) but practitioners are also questioning whether the response to N application has changed in modern dry bean production system. Unlike corn, wheat, or other N responsive crops, dry bean fix atmospheric N and convert it into a plant usable form through a symbiotic relationship with Rhizobium bacteria (Adams et al., 2016). George and Singleton (1992) observed the percentage of plant N derived from N fixation at physiological maturity (R7) when N fertilizer was applied at a rate of 8 lb N/acre ranged from 32-69% and 16-18% for soybean (Glycine max L. Merr.) and dry bean, respectively. Thus, dry bean is considered a relatively poor N fixer and often requires supplemental N fertilization in addition to soil N contributions (i.e., residual N and mineralized N) for optimal plant growth and yield (Mckenzie et al., 2000; Farid et al., 2016). Yield increases from N fertilization may generally occur on N-poor soils (i.e., low residual N with low SOM) but are also dependent on crop rotation, agronomic practices, organic amendments, and environmental conditions (Westermann et al., 1981). Current university guidelines recommend the application of 40-60 lb N/acre, but yield increases from N fertilization over the past 30 years were generally inconsistent (Warncke et al., 2009). Moraghan et al. (1991) found the application of N fertilizer had no effect or decreased navy bean yield at three of four locations while Eckert et al. (2011) reported no yield increase to N fertilization across three pinto bean cultivars. However, under low residual soil NO3-N concentrations, Blaylock (1995) reported a yield 108 increase across varying N levels and Soratto et al. (2014) found N application increased early- season plant growth and reduced plant mortality later concluding N fertilizer was important for dry bean establishment. Despite potential benefits to N fertilizer application, additional risk from over-application exists in the form of reduced N fixation, delayed maturity, increased white mold (caused by Sclerotinia sclerotiorum) disease due to greater canopy density, and increased risk for environmental N losses (Warncke et al., 2009; Eckert et al., 2011; Argraw and Akuma, 2015; Akter et al., 2018). Sulfur has not been recommended in Michigan dry bean production due to sufficient soil S supply or S carryover from application to other N-responsive crops within the dry bean rotation including wheat (Triticum aestivum L.), sugarbeet (Beta vulgaris L.), and corn (Zea mays L.) (Warncke et al., 2009). Sulfur deficiencies have increased due to an 85% decrease in atmospheric S deposition in Michigan between 1980 and 2019, greater usage of concentrated fertilizers containing little or no S. and increased S removal from greater biomass production and grain yields (McGrath and Zhao, 1995; Chien et al., 2009; National Atmospheric Deposition Program, 2019). Hitsuda et al. (2005) suggested that S application at early growth stages should be considered to provide sufficient S supply throughout the growing season as developing roots cannot access S accumulated deeper in the soil profile. However, S mineralization increases with soil temperatures between 68 to 104ºF (Havlin et al., 2014), and in the current study warm soil temperatures (64-68ºF) at dry bean planting (i.e., June) indicate the potential for S mineralization to satisfy dry bean S requirements. The probability of an S response in dry bean may be site- specific depending upon SOM, residual soil S, and crop rotation as observed in other crops including soybean (Kaiser and Kim, 2013). However, soil S analysis may not be a reliable indicator of grain yield responses to S application as S concentration varies considerably 109 between different soil horizons thus plant analysis may be a better diagnostic tool for identifying S sufficiency (Sawyer and Barker, 2002; Hitsuda et al., 2005; Culman et al., 2020). Glowacka et al. (2019) observed a 14.5% yield increase and improved grain quality from S application prior to planting, thus concluding S fertilization should be included in dry bean crop management. In a review of dry bean responses to S fertilization, Pias et al. (2019) found 50% (n=6) of dry bean trials increased grain yield by 12% in response to S application when the concentration of soil available SO4-S was below critical. Conversely, Nascente et al. (2017b) found six different dry bean cultivars did not differ in grain yield response to S fertilizer application. Apart from grain yield and quality, S application may potentially impact nodulation in dry bean because legumes that acquire N through BNF typically have a greater S requirement than legumes which only use soil N (Sulieman et al., 2013). Nascente et al. (2017a) found S application between 0-54 lb S/acre did not influence the number of nodules or dry mass of nodules per root. Although S plays a significant role in N assimilation by N fixing bacteria (Pacyna et al., 2006), few data exist examining S application on nodulation in dry bean. Sulfur fertilizers often contain either SO4-S, elemental S, or a combination of the two (SO4-S and elemental S). Applied prior to planting, SO4-S fertilizer is readily available as compared to elemental S which must be oxidized to SO4-S through microbial activity prior to plant uptake (Boswell and Friesen, 1993). Oxidation to convert elemental sulfur into SO4-S is slow and depends upon soil environmental conditions (i.e., temperature and moisture) suitable for aerobic microbial activity (Havlin et al., 2014). However, under leaching conditions the total recovery of elemental S over an extended period (i.e., five years) may reach or surpass SO4-S (Degryse et al., 2021). Combined with the long-term S availability from the slow oxidation of elemental S and a lower potential for short-term losses, elemental S offers the potential to reduce 110 future S deficiencies associated with uncertain soil S availability (Goyal et al., 2021). Although a combination of both SO4-S and elemental S may be useful to provide both immediate and long- term S availability (Norton et al. 2013), grain yield response to elemental S or combined (SO4-S and elemental S combinations) has been inconsistent. Across laboratory, greenhouse, and field studies concerning S fertilizer sources, Chien et al. (2016) concluded granular fertilizers containing elemental S or a combination of elemental S and SO4-S provide less available S during the first growing season after fertilizer application as compared to traditional SO4-S fertilizer sources. However, in soybean, Purucker and Steinke (2020) discovered the application of a combined (SO4-S and elemental S) fertilizer increased grain S accumulation 8% compared to the non-fertilized control possibly due to late-season S availability and uptake from elemental S oxidation. Continued yield improvements in modern dry bean varieties and increased crop (i.e., corn, wheat, and sugarbeet) responses from S application in Michigan necessitate a greater understanding of how N and S fertilizer application impact dry bean. The objective of this study was to 1) evaluate the effect of N application rates across multiple dry bean varieties on grain yield, dry matter accumulation, and root nodulation and -2) evaluate S fertilizer rate and source effects across dry bean varieties for grain yield and root nodulation. Materials and Methods Location and Site Description Nitrogen rate, sulfur rate, and sulfur source field studies were conducted in 2019 and 2020 at the Michigan State University Saginaw Valley Research and Extension Center near Richville, MI (43°23’57.3”N, 83°41’49.7”W) on a non-irrigated Tappan-Londo loam soil (fine- 111 loamy, mixed, active, calcareous, mesic Typic Enduaquolls). Soil samples collected prior to fertilizer application to an 8-inch depth were analyzed for pH (1:1 soil/water), cation exchange capacity (CEC), soil organic matter (SOM) (loss on ignition), P (Bray-P1), K (ammonium acetate extractable K), and S (0.25 M KCL); and to a 1-ft depth for NO3-N (cadmium reduction) (Table 3.01). All sites were previously cropped to corn and were either fall chisel or moldboard plowed (9-inch depth) followed by two passes of a soil finisher (3-inch depth) prior to planting. Full season pest control followed Michigan State University best management practices. Environmental data were collected using the Michigan State University Enviro-weather (https://enviroweather.msu.edu, Michigan State University, East Lansing, MI). Temperature and precipitation 30-year means were obtained from the National Oceanic and Atmosphere Administration (NOAA, 2019). Experimental Design and Procedures for N rate Studies were arranged as a randomized complete split-plot design with four replications. The main plot factor was dry bean variety and the subplot factor was N rate. Varieties consisted of ‘Zenith’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Black Bear’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Viper’ small red bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); and ‘Merlin’ navy bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine). Six N rates (0, 30, 60, 90, 120, and 150 lb N/acre) were broadcast as urea (46-0-0 N-P-K) and incorporated prior to planting (3-inch depth) on 18 June 2019 and 04 June 2020, respectively. Individual 4-row plots measured 15-ft in length and 7-ft in width. Dry beans were planted using a White 6000 series planter (AGCO Corp., Duluth, GA) at a base seeding rate of 144,000 seeds/acre in 20-inch rows on 19 June 2019 and 04 June 2020. 112 Post-harvest NO3-N was collected from three soil cores (1-ft depth) in the center two rows of each plot. Nodules were counted six weeks after emergence from five consecutive plants/plot. Leaf nutrient analysis was collected from the uppermost fully developed trifoliate of 20 plants/plot. Aboveground plant biomass was sampled from five consecutive plants/plot when at least 50% of the crop achieved the R5 growth stage. Dry weight was determined by drying plant tissue at 150F to approximately 0% moisture. White mold incidence was calculated by rating thirty consecutive plants/plot for disease infection at maturity (R8). Grain yield, moisture, and test weight were determined by direct harvesting the center two rows of each plot with a Wintersteiger Quantum research combine (Winterstieger AG, Austria). Final grain yields were corrected to 18% moisture. Economic return was calculated using an average local cash price of $30.00, $32.00, and $32.00/cwt for black, navy, and small red bean, respectively, and input costs of $0.45 lb N for urea. Fertilizer application costs of $5.22/acre were estimated for the prior to planting broadcast application using Michigan State University Extension Custom Machine and Work Rate Estimates (Stein, 2019). Net economic return was calculated using a partial budget subtracting input cost from gross revenue (i.e., grain price multiplied by yield). Experimental Design and Procedures for S rate Studies were arranged as a randomized complete split-plot design with four replications. The main plot factor was dry bean variety and the subplot factor was S rate. Varieties consisted of ‘Zenith’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Black Bear’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Viper’ small red bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); and ‘Merlin’ navy bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine). Four S rates (0, 25, 50, and 100 lb S/acre) were broadcast as 113 gypsum (0-0-0-23-18 N-P-K-Ca-S) and incorporated prior to planting (3-inch depth) on 18 June 2019 and 04 June 2020, respectively. All plots received 60 lb N/acre using urea (46-0-0 N-P-K) with S application before planting. Individual 4-row plots measured 15-ft in length and 7-ft in width. Dry beans were planted using a White 6000 series planter (AGCO Corp., Duluth, GA) at a base seeding rate of 144,000 seeds/acre in 20-inch rows on 19 June 2019 and 04 June 2020. Nodules were counted six weeks after emergence from five consecutive plants/plot. Leaf nutrient analysis was collected from the uppermost fully developed trifoliate of 20 plants/plot. Grain yield, moisture, and test weight were determined by direct harvesting the center two rows of each plot with a Wintersteiger Quantum research combine (Winterstieger AG, Austria). Final grain yields were corrected to 18% moisture. Economic return was calculated using an average local cash price of $30.00, $32.00, and $32.00/cwt for black, navy, and small red bean, respectively, and input costs of $0.14 lb S for gypsum. Fertilizer application costs of $5.22/acre were estimated for the prior to planting broadcast application using Michigan State University Extension Custom Machine and Work Rate Estimates (Stein, 2019). Net economic return was calculated using a partial budget subtracting input cost from gross revenue (i.e., grain price multiplied by yield). Experimental Design and Procedures for S source Studies were arranged as a randomized complete split-plot design with four replications. The main plot factor was dry bean variety and the subplot factor was S fertilizer source. Varieties consisted of ‘Zenith’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Black Bear’ black bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); ‘Viper’ small red bean (ADM Seedwest, Decatur, IL), a Type II (upright indeterminate short vine); and ‘Merlin’ navy bean (ADM Seedwest, Decatur, IL), a 114 Type II (upright indeterminate short vine). Gypsum (0-0-0-23-18 N-P-K-Ca-S), ammonium sulfate (AS) (21-0-0-24 N-P-K-S), and MicroEssentials® SZ® (MESZ) (Mosaic CO., Plymouth, MN) (12-40-0-10-1 N-P-K-S-Zn) were broadcasted and incorporated prior to planting (3-inch depth) at a rate of 25 lb S/acre on 18 June 2019 and 04 June 2020, respectively. All plots were balanced to receive 60 lb N/acre using urea (46-0-0 N-P-K) with S application before planting. Individual 4-row plots measured 15-ft in length and 7-ft in width. Dry beans were planted using a White 6000 series planter (AGCO Corp., Duluth, GA) at a base seeding rate of 144,000 seeds/acre in 20-inch rows on 19 June 2019 and 04 June 2020. Nodules were counted six weeks after emergence from five consecutive plants/plot. Leaf nutrient analysis was collected from the uppermost fully developed trifoliate of 20 plants/plot. Grain yield, moisture, and test weight were determined by direct harvesting the center two rows of each plot with a Wintersteiger Quantum research combine (Winterstieger AG, Austria). Final grain yields were corrected to 18% moisture. Economic return was calculated using an average local cash price of $30.00, $32.00, and $32.00/cwt for black, navy, and small red bean, respectively, and input costs of $0.45 lb N, $0.14 lb S, $0.77 lb S, and $2.95 lb S for urea, gypsum, AMS, and MESZ fertilizer treatments, respectively. Fertilizer application costs of $5.22/acre were estimated for the prior to planting broadcast application using Michigan State University Extension Custom Machine and Work Rate Estimates (Stein, 2019). Net economic return was calculated using a partial budget subtracting input cost from gross revenue (i.e., grain price multiplied by yield). Statistical Analyses Statistical analyses were performed using PROC GLIMMIX in SAS 9.4 (SAS Institute, 2012) at α = 0.10. Site-year, variety, and fertilizer application were considered fixed effects and 115 the replication as random. Normality of residuals were examined using the UNIVARIATE procedure (P ≤ .05). Squared and absolute values of residuals were examined with Levene’s Test to confirm homogeneity of variances (P ≤ .05). Least square means were separated using the LINES option of the slice statement when ANOVA indicated a significant interaction (P ≤ .10). Pearson product-moment correlations were derived using the REG procedure of SAS to investigate the relationship between dry matter accumulation, grain yield, and white mold incidence. Results and Discussion Environmental Conditions Cumulative 2019 and 2020 growing season (June-September) precipitation was 4% greater and 21% below 30-yr averages, respectively (Table 3.02). Above average 2019 precipitation occurred soon after planting resulting in soil crusting and greater incidence of soil- borne disease (i.e., Fusarium solani and Rhiozoctonia solani root rot) which may have limited vegetative and root growth, nodulation, yield, and response to N and S application. Optimal spring 2020 planting conditions and normal summer precipitation patterns resulted in greater yields than 2019. Growing season air temperatures were within 5% of the 30-yr average across both years. Dry Bean Response to Nitrogen Rate Across site years N rate did not significantly impact V2 plant stand (data not shown). Sorrato et al. (2014) found N application improved the establishment of dry bean when N was applied pre-sowing in a no-till system due to greater initial plant growth and a reduction in plant mortality during early vegetative stages. However, dry bean does not tolerate N fertilizer to be 116 placed with the seed at planting as salt injury may decrease plant population (Warncke et al., 2009). Thus, the potential to reduce plant stand at early vegetative stages may also exist for high rates of pre-plant and incorporated N (i.e., > 90 lb N/acre) prior to planting. Two inches of rain two days after 2019 planting and one inch of rain six days after 2020 planting may have mitigated risk for salt injury by solubilizing and moving N out of the immediate germination zone (Steinke and Bauer, 2017). Although plant stand reductions did not occur in the current study, growers should use caution when applying high N rates (i.e., > 90 lb N/acre) prior to or at- planting due to potential saltation. Tissue R1 uppermost trifoliate N concentration was significantly (P < 0.01) affected by N rate in both years but not variety-specific (Table 3.03). Compared to no N, 120 lb N/acre increased N concentration in the uppermost trifoliate 18 and 10% in 2019 and 2020, respectively, suggesting greater N availability due to N application likely resulted in increased tissue N uptake. Previous studies found the application of N increased dry bean tissue N concentration (Liebman et al., 1995; Sorratto et al., 2014), and according to Ambrosano et al. (1997), leaf N concentrations between 3.0-5.0% were considered adequate for optimal growth, thus there was no indication of early-season N deficiencies in the current study. Nodulation numbers ranged between 0.9-4.3 and 3.7-7.9 nodules plant-1 across N rates in 2019 and 2020, respectively (Table 3.03). Dry soil conditions (i.e., 10% below the 30-yr average) during July and August 2019 likely reduced nodulation compared to 2020 (Kumarasinghe et al., 1992). However, other environmental factors may influence nodulation including pH, salinity, soil temperature, and P availability (Farid et al., 2016). Nodulation was not affected up to 60 lb N/acre in 2020 with significant decreases at rates > 60 lb N/acre. Results in 2020 agree with Argraw and Akuma (2015) who reported decreased nodulation with increased 117 rates of N fertilizer. Nodulation was significantly affected by variety (P = 0.06) and N rate (P = 0.06) in 2020. Previous research suggested plant nodulation varies between dry bean genotypes and varieties thus impacting response to applied N (Wolyn et al., 1991; Fageria et al., 2013). Compared to the black bean varieties ‘Zenith’ and ‘Black Bear’, the navy bean variety ‘Merlin’, produced 3.5 and 3.4 fewer nodules plant-1, respectively. Aboveground R5 dry matter was significantly affected by N rate (P ≤ 0.01) across years (Table 3.04). At N application rates from 0-150 lb N/acre, aboveground dry matter ranged from 3650 to 5314 lb/acre and 4355 to 6687 lb/acre in 2019 and 2020, respectively. Reduced 2019 aboveground dry matter production was the result of below average precipitation (i.e., less than 10% of 30-yr average) during July and August. Biomass production significantly increased up to 60 lb N/acre with no observed differences at N rates > 60 lb N/acre. Lack of plant height differences suggests additional aboveground production was likely the result of greater canopy density (Table 3). However, growers should be aware to not confuse greater in-season biomass production with increased grain yield. Results agree with previous research observing increased dry matter production following N application (Moraghan et al., 1991; George and Singleton, 1992). However, Edje et al. (1975) found dry matter production peaked at 107 lb N/acre and decreased thereafter when evaluating N rates between 0-178 lb N/acre. Since 1975, dry bean varieties have shifted from a Type III (indeterminate prostrate) to a Type II (indeterminate upright) growth habit partially due to greater harvestability (Soltani et al., 2016). Compared to Type II, type III plants are more vulnerable to disease and lodging due to dense canopy cover and weaker main stems unable to support branches and pods. Through improvements in plant canopy architecture, grain yield has simultaneously increased during this same time due in part to greater N use efficiency and N fixation as modern dry bean varieties may potentially require 118 less N than older varieties (Fageria and Santos, 2008; Akter et al., 2017; Heilig et al., 2017). In contrast to Edje et al. (1975), aboveground dry matter production peaked at a much lower N rate (60 lb N/acre) with no significant decreases in dry matter beyond 60 lb N/acre in the current study. Findings suggest the possibility that modern dry bean varieties may require less N compared to older varieties partially due to improvements in breeding. Precipitation that was 3-6% above 30-yr averages in July and August 2020 coupled with cool September air temperatures and dense canopy biomass may have provided favorable conditions for white mold (caused by Sclerotinia sclerotiorum). White mold did not occur in 2019 potentially due to a low number of sclerotia within the field tested and unfavorable environmental conditions limiting biomass production, canopy development, apothecia production, and plant infection. White mold incidence was significantly influenced by N rate (P = 0.02) and variety (P = < 0.01) in 2020 (Table 3.04). The small red bean variety ‘Viper’ increased white mold incidence up to 73% compared to the black bean varieties ‘Zenith’ and ‘Black Bear’ and 52% compared to the navy bean variety ‘Merlin’. Although ‘Viper’ is classified as a Type II (indeterminate upright short vine) variety, visual observations suggest ‘Viper’ may potentially be more prone to a closed canopy and sclerotinia infection due to a greater vining growth habit compared to ‘Zenith’, ‘Black Bear’, and ‘Merlin’ (Schwartz et al., 1978). However, white mold incidence and severity in commercially acceptable varieties is not solely dependent on plant architectural traits but instead a combination of physiological resistance and plant architectural traits (Schwartz et al., 1987). White mold incidence increased with N application greater than 60 lb N/acre and appeared to coincide with aboveground dry matter production. Thus, growers should take caution not to over apply N as stimulated foliage growth can create a favorable microenvironment for white mold disease and reduce grain yield 119 potential (Miklas et al., 2013). Additional cultural practices including row spacing, seeding rate, irrigation, and variety selection may affect white mold disease risk and should be considered prior to making N management decisions (Coyne et al., 1974; Schwartz et al., 1987; Kolkman and Kelly, 2002; Ando et al., 2007). Nitrogen rate and variety did not interact to affect grain yield indicating N application rates do not require adjustments solely based on variety (Table 3.05). Similar grain yield results were obtained in Alberta, where four commercial dry bean varieties (i.e., great northern, small red, pinto, and pink bean) under irrigation did not interact with N application rates (Mckenzie et al., 2000). Westermann et al. (1981) found more than half of total N uptake occurred during vegetative growth in which N fixation may be inadequate to satisfy plant N demand, suggesting that soil-derived N (i.e., residual soil N and mineralized N) and N fertilizer may be critical components for early-season N requirements (George and Singleton, 1992). However, in addition to varying rates of plant N demand from year to year, estimating N supply from N fixation and soil-derived N sources is difficult in part due to 1) by nature the environment is random and 2) biological processes (i.e., N mineralization and N fixation) which influence N supply are independent (Raun et al., 2019). These uncertainties create ambiguity when attempting to predict the correct amount of N fertilizer to apply prior to planting without also reducing the N fixation capabilities of the plant. The application of N prior to planting can help account for environmental variability and may affect grain yield more so than N applied after emergence. However, unless N fixation and soil-derived N supply cannot meet plant N requirements, the likelihood of a grain yield response to N application may be low (Sorrato et al., 2013; Sorrato et al., 2014). In both years residual soil NO3-N measured 18 lb NO3-N/acre in the top 0-1 ft and N rate did not significantly increase grain yield. Although average grain yield was 120 71% greater across N rates in 2020 compared to 2019 indicating a potentially greater seed N requirement and therefore increasing the likelihood of a grain yield response to N application, data suggest timely precipitation and N supply from N fixation and soil derived N (i.e., 18 lb residual NO3-N/acre in the 0-1 ft depth and mineralized N) were adequate to satisfy plant and seed N demand. Similar findings were reported by Eckert et al. (2011) and Moraghan et al. (1991), who both observed that N application did not increase grain yield above a soil NO3-N content of 50 and 14 lb NO3-N/acre, respectively. Due to a shorter-growing season (i.e., 85 to 100 d), variable June planting conditions, and the unpredictable nature of biological processes associated with N supply and demand, there is some justification for N application in dry bean to ensure yield potentials. Growers may also wish to consider fertilizer placement options as another method to account for some early- to mid-season weather variability, increase nutrient efficiencies, and improve the overall sustainability of the dry bean cropping system. Post-harvest soil residual NO3-N was significantly influenced by N rate but not dry bean variety across both years. Residual NO3-N remaining in the soil following harvest was similar at N rates between 0-60 and 0-90 lb N/acre in 2019 and 2020, respectively (Table 3.04). Nitrogen application rates > 120 lb N/acre maximized post-harvest soil residual NO3-N indicating application rates were in excess of crop removal. Findings suggest N application greater than grain requirements may potentially increase the risk for environmental N losses due to the ensuing 7–8-month period with little or no plant growth or ground cover prior to spring planting and may also affect the need for starter fertilizer application to the subsequent cash crop. Dry Bean Response to Sulfur Rate and Source Grain yield was significantly influenced by variety in 2020 but not affected by S rate or S source across years (Table 3.06, 3.07). Soil S testing may not be a reliable indicator for grain 121 yield response, and large variations in S concentrations can occur between soil horizons (Warncke et al., 2009; Culman et al., 2020). Soil SO4-S occurrence may be environmentally dependent and site specific, thus soil texture (i.e., SOM) and tissue S concentration may provide a better indication for predicting S availability (Hitsuda et al., 2008; Kaiser and Kim, 2013; Culman et al., 2020). Michigan nutrient management guidelines suggest the critical S concentration within the uppermost trifoliate at R1 is between 0.2%-0.4% S (Vitosh et al., 1995). No S application across both years resulted in tissue S concentrations of 0.25% (Table 3.08) indicating an unlikely response to S application. Field sites consisted of a loam soil with SOM between 2.4 and 2.6% (Table 3.01) suggesting sufficient S may have been available for dry bean growth. Under low soil S conditions nodulation may decrease because S is a key constituent of the nitrogenase enzyme S (Hago and Salama, 1987). However, nodulation was not impacted by S rate which agrees with adequate soil S levels as shown by tissue S concentrations, SOM levels, and lack of grain yield differences. Notably warm soil temperatures at planting (64-68ºF) and S application in more S responsive crops (i.e., corn and wheat) rotated previous to dry bean may reduce the need for supplemental S fertilization. While MESZ is a co-granulated fertilizer containing a mixture of both SO4-S and elemental S, thus providing some degree of early- and late-season S availability, elemental sulfur must oxidize to SO4-S by soil microbes prior to becoming plant available (Norton et al., 2013). To allow time for oxidation to take place prior to crop uptake elemental S may require application several months before the growing season (Havlin et al., 2014; Culman et al., 2020). Previous research has found available S from the application of an elemental S and SO4-S mixture may largely come from the SO4-S component for the first crop or in the subsequent years after S application (Chien et al., 2016; Degryse et al., 2021). In the current study, all S sources were applied prior to planting. Dry bean is a short- 122 season crop (i.e., 85 to 100 d maturity) creating potential difficulties in allowing for the elemental S component within MESZ to oxidize in time for crop uptake. Gypsum is a common mineral mined from surface and underground deposits and is a readily available and cost- effective source of S within Michigan compared to AS and MESZ fertilizers. However, both AS and MESZ fertilizers contain N in addition to S and are therefore beneficial where both N and S are required. Although gypsum is also a source of calcium (Ca), most soils in Michigan contain sufficient Ca for field crop production and in the current study exchangeable Ca levels (1850- 2300 ppm) in 2019 and 2020 suggest no response to Ca was expected (Warncke et al., 2009; Cullman et al., 2020). Compared to MESZ, gypsum increased economic return 20% in 2020 indicating the low cost of gypsum offset lack of yield of differences observed between S sources (Table 3.07). Previous research in dry bean has found nodulation is largely determined by the ratio between N supply and N demand (George and Singleton, 1992; Salvagiotti et al., 2008; Aker et al., 2008; Argraw and Akuma 2015). In 2020 gypsum reduced nodulation up to 2.2 nodules plant-1 compared to AS and MESZ (Table 3.08). However, all S sources were balanced to receive 60 lb N/acre indicating it is unlikely N supply influenced nodulation. Additionally, relatively small differences between nodule number per plant among S sources suggest results may not be biologically significant. Implications for Dry Bean Growers Two black bean, one small red bean, and one navy bean variety responded similarly to N rate, S rate, and S source, implying the application of N and S may not require adjustments based on specific varieties. While a lack of grain yield response to N application suggests N supply from biological nitrogen fixation and soil-derived N (i.e., residual soil NO3-N and mineralized 123 N) were sufficient to satisfy plant N requirements, weather variability can impact early-season N supply and when coupled with a short dry bean growing season (i.e., 85 to 100 d) may support some degree of N fertilizer application to ensure yield potential. Results indicate S application may not be warranted in dry bean grown on fine-textured Michigan soils with > 2% SOM, which agrees with previous reports for this region. Due to the lag time required for elemental S oxidation to SO4-S, the potential for elemental S to contribute to dry bean S requirements may be limited especially considering the short growing season of this crop and the rotation of dry bean with other potentially S responsive crops (e.g., corn and wheat). Although due to lack of grain yield improvements economic return was not impacted by N or S applications, increased input costs from higher N or S rates may decrease profitability without simultaneous grain yield increases. Incremental increases in N rate increased R5 aboveground dry matter accumulation and R1 trifoliate N concentrations but did not translate into greater grain yield. Rather, increased N rates (i.e., ≥ 60 lb N/acre) generally increased the risk for white mold infection and decreased nodulation in one of two years. Thus, growers should be aware of and consider the risks for excess N applications, which may ultimately reduce grain yield potential and increase environmental loss. Future research verifying dry bean response to N and S application on coarse-textured, irrigated soils in which N and S deficiencies may more commonly occur may be warranted. Acknowledgements The authors would like to thank the USDA National Institute of Food and Agriculture, the Michigan Department of Agriculture and Rural Development, the Michigan Dry Bean Commission, Michigan State University AgBioResearch, and the Michigan State University 124 College of Agriculture and Natural Resources for partial funding and support of this research. In addition, the authors would like to thank Andrew Chomas, research farm staff, and undergraduate research assistants for their technical assistance in the field. 125 APPENDICES 126 APPENDIX A: CHAPTER 3 TABLES Table 3.01. Soil chemical properties, mean P, K, and S concentrations (0-8 inches), and NO3-N content (0-1 ft), Richville, MI, 2019-2020. Soil test valuesa Year pH CEC SOM P K S NO3-N ___________________ meq/100 g % ppm___________________ lb/acre 2019 7.8 15.1 2.6 16 124 6 18 2020 7.0 13.0 2.4 43 162 9 18 a Soil test values were obtained prior to fertilizer application. 127 Table 3.02. Monthlya and 30-yr averageb cumulative precipitation and air temperature for the dry bean-growing season (June-September), Richville, MI, 2019-2020. Year June July August September Total _____________________________________ _____________________________________ in 2019 7.0 2.4 1.1 3.8 14.3 2020 1.4 3.2 3.4 2.8 10.8 30-yr avg 3.5 3.1 3.2 3.9 13.7 ˚F _____________________________________ _____________________________________ 2019 65.1 72.7 67.9 64.2 269.9 2020 69.1 74.7 70.6 60.4 274.8 30-yr avg 67.5 71.8 69.7 62.2 271.2 a Monthly precipitation and air temperatures collected from MSU Enviro-weather (https://enviroweather.msu.edu). b 30-yr averages collected from the National Oceanic and Atmosphere Administration (https://www.ncdc.noaa.gov/cdo-web/datatools/normals) 128 Table 3.03. Influence of dry bean variety and N rate on tissue N concentration, nodule count, and plant height, Richville, MI, 2019-2020. Plant height Tissue N conc. Nodule number Treatment 2019 2019 2019 2019 2019 2020 ___________ ___________ _____________ _____________ ______ inches % nodules/plant______ Variety Zenith 20 22 ba 4.5 4.6 2.2 7.0 a Black Bear 20 23 ab 4.5 4.5 2.9 6.9 a Viper 21 21 c 4.5 4.6 3.2 4.2 ab Merlin 21 24 a 4.4 4.4 1.0 3.5 b P>F 0.14 0.01 0.93 0.19 0.16 0.02 N rate, lb N/acre 0 20 22 4.0 e 4.2 d 4.3 7.7 a 30 21 22 4.3 d 4.4 cd 3.2 7.9 a 60 21 22 4.4 cd 4.6 ab 1.9 5.0 ab 90 21 23 4.6 bc 4.5 bc 2.6 3.7 b 120 21 22 4.7 ab 4.6 ab 0.9 4.2 ab 150 21 23 4.8 a 4.7 a 1.0 4.0 b P>F 0.49 0.45 <0.01 <0.01 0.34 0.06 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. 129 Table 3.04. Influence of dry bean variety and N rate on R5 aboveground dry matter accumulation, white mold incidence, and post-harvest residual NO3-N (0-1 ft), Richville, MI, 2019-2020. Aboveground dry matter White molda Post-harvest NO3-N Treatment 2019 2020 2020 2019 2020 ______________ ______________ _______ _______ ___________ ___________ lb/acre % lb N/acre Zenith 4545 5445 13 c 27 23 Black Bear 4510 5900 15 c 27 17 Viper 4791 5688 48 a 27 24 Merlin 4667 6326 23 b 29 19 P>F 0.89 0.42 <0.01 0.80 0.16 N rate, lb N/acre 0 3650 cb 4355 c 22 b 20 c 17 c 30 4231 bc 5330 bc 20 b 22 bc 15 c 60 4692 ab 6687 a 29 a 24 bc 17 c 90 5229 a 6443 a 21 b 28 b 19 bc 120 4654 ab 6434 a 29 a 37 a 26 ab 150 5314 a 5791 ab 29 a 35 a 32 a P>F 0.01 <0.01 0.02 <0.01 <0.01 a No data collected in 2019 due to lack of white mold disease. b Least square means within each column followed by a common letter are not significantly different at α = 0.10. 130 Table 3.05. Influence of dry bean variety and N rate on grain yield and economic return, Richville, MI, 2019-2020. Grain yielda Economic returnb Treatment 2019 2020 2019 2020 ____________ ____________ ___________ ___________ lb/acre US$/acre Variety Zenith 2239 3531 cc 634 1021 c Black Bear 2331 3850 b 661 1117 b Viper 2262 4223 a 686 1314 a Merlin 2222 3724 bc 673 1153 b P>F 0.93 0.01 0.80 <0.01 N rate, lb N/acre 0 2324 3637 721 1128 30 2110 3781 632 1156 60 2199 3915 649 1184 90 2335 3807 681 1136 120 2277 3883 647 1146 150 2337 3968 650 1157 P>F 0.87 0.35 0.86 0.87 a Grain yield adjusted to 18% moisture. b Economic return calculated as ((dry bean grain price x grain yield) – partial budget costs)). c Least square means within each column followed by a common letter are not significantly different at α = 0.10. 131 Table 3.06. Impact of dry bean variety and S rate on grain yield and economic return, Richville, MI, 2019-2020. Grain yielda Economic returnb Treatment 2019 2020 2019 2020 ____________ ____________ ___________ ___________ lb/acre US$/acre Variety Zenith 2300 3762 bc 652 1088 b Black Bear 2209 4358 a 623 1267 a Viper 2077 3993 ab 625 1238 a Merlin 2157 4218 a 650 1310 a P>F 0.69 0.08 0.93 0.03 S rate, lb S/acre 0 2172 4040 643 1220 25 2208 4137 648 1246 50 2213 4067 646 1222 100 2150 4088 613 1215 P>F 0.95 0.80 0.80 0.73 a Grain yield adjusted to 18% moisture. b Economic return calculated as ((dry bean grain price x grain yield) – partial budget costs)). c Least square means within each column followed by a common letter are not significantly different at α = 0.10. 132 Table 3.07. Influence of dry bean variety and S source on grain yield and economic return, Richville, MI, 2019-2020. Grain yielda Economic returnb Treatment 2019 2020 2019 2020 ____________ ____________ ___________ ___________ lb/acre US$/acre Variety Zenith 2142 3935 586 1124 Black Bear 2075 4301 566 1234 Viper 2026 4066 592 1244 Merlin 2060 4000 603 1223 P>F 0.94 0.28 0.94 0.21 S source Gypsum 2208 4119 648 aa 1241 d AS 2040 4069 591 ab 1219 e MESZ 1979 4037 521 b 1160 P>F 0.21 0.81 0.02 0.12 a Grain yield adjusted to 18% moisture. b Economic return calculated as ((dry bean grain price x grain yield) – partial budget costs)). c Least square means within each column followed by a common letter are not significantly different at α = 0.10. d AS: ammonium sulfate (21-0-0-24 N-P-K-S). e MESZ: MicroEssentials SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). 133 Table 3.08. Dry bean variety and S rate effects on tissue S concentration and nodule count, Richville, MI, 2019-2020. Tissue S concentration Nodule number Treatment 2019 2020 2019 2020 _____________ _____________ ______ % nodules/plant______ Variety Zenith 0.29 aa 0.25 1.2 3.8 a Black Bear 0.26 b 0.25 3.2 2.5 ab Viper 0.24 c 0.25 4.0 2.2 b Merlin 0.25 bc 0.25 0.9 1.3 b P>F <0.01 0.18 0.17 0.05 S rate, lb S/acre 0 0.25 b 0.25 3.0 2.5 25 0.26 a 0.25 1.8 2.0 50 0.26 a 0.25 2.4 2.3 100 0.27 a 0.25 2.1 3.0 P>F 0.03 0.14 0.34 0.37 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. 134 Table 3.09. Dry bean variety and S source effects on tissue S concentration and nodule count, Richville, MI, 2019-2020. Tissue S concentration Nodule number Treatment 2019 2020 2019 2020 _____________ _____________ ______ % nodules/plant______ Variety Zenith 0.28 aa 0.26 1.5 bc 4.8 a Black Bear 0.27 b 0.25 2.6 ab 3.2 b Viper 0.25 c 0.25 3.6 a 2.3 bc Merlin 0.26 bc 0.25 0.9 c 1.1 c P>F 0.01 0.19 0.04 0.01 S source Gypsum 0.26 0.25 0.9 b 2.0 b AS 0.27 0.25 2.5 a 3.4 c MESZ 0.26 0.25 3.1 a 3.2 P>F 0.17 0.98 <0.01 0.13 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. b AS: ammonium sulfate (21-0-0-24 N-P-K-S). c MESZ: MicroEssentials SZ (Mosaic Co.) (12-40-0-10-1 N-P-K-S-Zn). 135 APPENDIX B: CHAPTER 3 DATA COLLECTED BUT NOT INCLUDED IN PUBLICATION Table 3.10. Dry bean variety and N rate effects on V2 and R8 plant stand, Richville, MI, 2019- 2020. 2019 2020 Treatment V2 R8 V2 R8 ____________________________ ____________________________ plants/acre Variety Zenith 117502 ba 106051 c 133269 a 126962 b Black Bear 110200 c 108208 c 123809 a 122813 b Viper 133933 a 130115 a 134255 a 139907 a Merlin 121817 b 123892 b 111196 b 109868 c P>F <0.01 <0.01 0.01 <0.01 N rate, lb N/acre 0 120241 116382 126713 119245 c 30 122232 118871 125966 125220 bc 60 122481 114764 130696 122979 bc 90 121983 116258 126713 132190 a 120 116755 116258 123477 126215 ab 150 121485 119867 120241 123477 bc P>F 0.79 0.83 0.16 0.05 a Least square means within each column followed by a common letter are not significantly different at α = 0.10. 136 LITERATURE CITED 137 LITERATURE CITED Akter, Z., Lupwayi N.Z., and Balasubramanian P.M. (2017). Nitrogen use efficiency of irrigated dry bean (Phaseolus vulgaris L.) genotypes in southern Alberta. Canadian Journal of Plant Science, 97(4): 610-619. Adams, M.A., Turnbull, T.L., Sprent, J.I., Buchmann, N. (2016). Legume are different: Leaf nitrogen, photosynthesis, and water use efficiency. Proc. Natl. Acad. Sci. U.S.A. 113, 4098–4103. Ambrosano, E.J., Tanaka, R.T., Mascarenhas, A.A. van Raij, B., Quaggio, J.A., and Cantarella. H. (1997). Legumes and oilseeds. In: B. van Raij et al., editors, Lime and fertilizer recommendations for the State of São Paulo. (In Portuguese.) 2nd ed. Tech. Bull. 100. Inst. Agronômico Campinas, SP, Brazil., p. 189–204. Ando, K., Grumet, R., Terpastra, K., and Kelly, J.D. (2007). Manipulation of plant architecture to enhance crop disease control. CAB Rev., 2(026): 1– 8. Argaw, A., and Akuma, A. (2015). Rhizobium leguminosarum bv. viciae sp. inoculation improves the agronomic efficiency of N of common bean (Phaseolus vulgaris L.). Environ Syst Res., 4, 11. Blaylock, A.D. (1995). Navy bean yield and maturity response to nitrogen and zinc, Journal of Plant Nutrition, 18:1, 163-178. Boswell, C.C., and Friesen, D.K. (1993). Elemental sulfur fertilizers and their use on crops and pastures. Fert. Res., 35:127–149. Chien, S.H., Teixeira, L.A., Cantarella, H., Rehm, G.W., Grant, C.A. and Gearhart, M.M. (2016). Agronomic Effectiveness of Granular Nitrogen/Phosphorus Fertilizers Containing Elemental Sulfur with and without Ammonium Sulfate: A Review. Agronomy Journal, 108: 1203-1213. Chien, S.H., Prochnow, L.I., and Cantarella. H. (2009). Recent developments of fertilizer production and use to increase nutrient efficiency and minimize environmental impacts. Adv. Agron., 102:261–316. Combs, S. M., Denning, J. L., & Frank, K. D. (2015). Sulfate-sulfur. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the North Central Region (pp. 81– 86). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. 138 Combs, S. M., & Nathan, M. V. (2015). Soil organic matter. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 121– 126). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Coyne, D.P., Steadman, J.R., and Anderson, F.N. (1974). Effect of modified plant architecture of great northern dry bean varieties (Phaseolus vulgaris) on white mold severity, and components of yield. Plant Dis. Rptr., 58: 379– 382. Culman, S., Fulford, A., Camberato, J., and Steinke, K. (2020). Tri-State Fertilizer Recommendations. Bulletin 974. College of Food, Agricultural, and Environmental Sciences. Columbus, OH: The Ohio State University. Degryse, F., Baird, R., Andelkovic, I., and McLaughlin, J.M. (2021). Long-term fate of fertilizer sulfate- and elemental S in co-granulated fertilizers. Nutr. Cycl. Agroecosyst., 120, 31– 48. Eckert, F.R., Kandel, H.J., Johnson, B.L., Rojas‐Cifuentes, G.A., Deplazes, C., Vander Wal, A.J. and Osorno, J.M. (2011). Row Spacing and Nitrogen Effects on Upright Pinto Bean Cultivars under Direct Harvest Conditions. Agronomy Journal, 103: 1314-1320. Edje, O.T., Mughogho, L.K. and Ayonoadu, U.W.U. (1975), Responses of Dry Beans to Varying Nitrogen Levels1. Agronomy Journal, 67: 251-255. Fageria, N.K., and A.B. Santos. (2008). Yield physiology of dry bean. Journal of Plant Nutrition 31: 983–1004. Fageria, N.K., Melo, L.C., and Oliveira, J. de. (2013). Nitrogen Use Efficiency in Dry Bean Genotypes. Journal of Plant Nutrition, 36:14, 2179-2190. Farid, M., Earl, H.J. and Navabi, A. (2016). Yield Stability of Dry Bean Genotypes across Nitrogen‐Fixation‐Dependent and Fertilizer‐Dependent Management Systems. Crop Science, 56: 173-182. Frank, K., Beegle, D., & Denning, J. (2015). Phosphorus. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 61– 66). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. George, T. and Singleton, P. (1992). Nitrogen Assimilation Traits and Dinitrogen Fixation in Soybean and Common Bean. Agronomy Journal, 84: 1020-1028. 139 Glowacka, A., Gruszecki, T., Szostak, B., and Michalek, S. (2019). The response of common bean to sulphur and molybdenum fertilization. International Journal of Agronomy 2019: Article ID 3830712. Goyal, D., Franzen, D.W., Cihacek, L.J. and Chatterjee, A. (2021). Corn response to incremental applications of sulfate-sulfur. Agronomy Journal. Accepted Author Manuscript. Hago, T., & Salama, M. (1987). The Effects of Elemental Sulphur on Shoot Dry Weight, Nodulation and Pod Yield of Groundnut (Arachis hypogaea) under Irrigation. Experimental Agriculture, 23(1), 93-97. Havlin, J. L., Tisdale, S. L., Beaton, J. D., and Nelson, W. L. (2014). Soil fertility and fertilizers: An introduction to nutrient management (8th ed.). Upper Saddle River, NJ: Pearson Prentice Hall. Heilig, J.A., Beaver, J.S., Wright, E.M., Song, Q. and Kelly, J.D. (2017). QTL Analysis of Symbiotic Nitrogen Fixation in a Black Bean Population. Crop Science, 57: 118-129. Hitsuda, K., Toriyama, K., Subbarao, G.V. and Ito, O. (2008). Sulfur Management for Soybean Production. In J. Jez (Ed.), Sulfur: A Missing Link between Soils, Crops, and Nutrition, (pp. 117-142), Madison, WI: ASA, CSSA, and SSSA. Hitsuda, K., Yamada, M. and Klepker, D. (2005). Sulfur Requirement of Eight Crops at Early Stages of Growth. Agronomy Journal, 97: 155-159. Kaiser, D.E., and Kim, K. (2013). Soybean response to sulfur fertilizer applied as a broadcast or starter using replicated strip trials. Agronomy Journal, 105:1189-1198. Kolkman, J.M., and Kelly, J.D. (2002). Agronomic traits affecting resistance to white mold in common bean. Crop Science, 42: 693– 699. Kumarasinghe, K.S., Kirda, C., Mohamed, A.R.A.G., Zapata, F., and Danso, S. K. A. (1992). 13C isotope discrimination correlates with biological nitrogen fixation in soybean (Glycine max (L.) Merrill). Plant Soil, 139, 145–147. Liebman, M., Corson, S., Rowe, R.J. and Halteman, W.A. (1995), Dry Bean Responses to Nitrogen Fertilizer in Two Tillage and Residue Management Systems. Agronomy Journal, 87: 538-546. McGrath, S.P., and Zhao, F.J. (1995). A risk assessment of sulphur deficiency in cereals using soil and atmospheric deposition data. Soil Use Manage., 11:110–114. 140 McKenzie, R. H., Middleton, A. B., Seward, W. R., Gaudiel, K., Wildschut, C., and Bremer, E. (2001). Fertilizer responses of dry bean in southern Alberta. Canadian Journal of Plant Science, 81(2): 343-350. Miklas, P.N., Porter, L.D., Kelly, J.D., and Myers, J.M. (2013). Characterization of white mold disease avoidance in common bean. Eur. J. Plant Pathol., 135: 525– 543. Moraghan, J.T., Lamb, J.A. and Albus, W. (1991). Nitrogen Fertilizer Requirements of Navy Beans in the Northern Great Plains. Journal of Production Agriculture, 4: 204-208. Nascente, A.S., Silveria, P.M, Silvia, J.G., and Ferreira, E.P.B. (2017a). Depth of sulfur fertilization as affecting nodulation and grain yield of common bean. Colloquium Agrariae, 13: 9-18. Nascente, A.S., Stone, L.F., and Melo, L.C. (2017b). Common bean grain yield as affected by sulfur fertilization and cultivars. Revista Ceres, 64(5), 548-552. National Atmospheric Deposition Program. (2020). NADP/NTN monitoring location MI26. NADP. Retrieved from http://nadp.slh.wisc.edu/data/sites/siteDetails.aspx?net=NTN&id=MI26 National Oceanic and Atmospheric Administration. (2019). National climatic data center. NOAA. http://www.ncdc.noaa.gov Norton, R., Mikkelsen, R., and Jensen, T. (2013). Sulfur for plant nutrition. Better Crops Plant Food, 97: 10– 12. Peters, J. B., Nathan, M. V., & Labowski, C. A. M. (2015). pH and lime requirement. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the north central region (pp. 41– 47). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Pias, O.H.C., Tiecher, T., Cherubin, M.R., Mazurana, M., and Bayer, C. (2019). Crop yield responses to sulfur fertilization in Brazilian no-till soils: a systematic review. Rev Bras Cienc Solo., 43:e0180078. Piha, M.I. and Munns, D.N. (1987). Nitrogen Fixation Capacity of Field‐Grown Bean Compared to Other Grain Legumes1. Agronomy Journal, 79: 690 696. Purucker, T, Steinke, K. (2020). Soybean seeding rate and fertilizer effects on growth, partitioning, and yield. Agronomy Journal, 112: 2288– 2301. 141 Raun, W.R., Dhillon, J., Aula, L., Eickhoff, E., Weymeyer, G., Figueirdeo, B., Lynch, T., Omara, P., Nambi, E., Oyebiyi, F. and Fornah, A. (2019). Unpredictable Nature of Environment on Nitrogen Supply and Demand. Agronomy Journal, 111: 2786-2791. SAS Institute. (2012). The SAS System for windows. Version 9.4. Cary, NC: SAS Institute. Sawyer, J.E., and Barker, D.W. (2002). Corn and soybean response to sulfur application on Iowa soils. In: Proceedings of the 32nd North Central Extension–Industry Soil Fertility Conference, Des Moines, IA. 20–21 Nov. 2002. Potash and Phosphate Inst., Brookings, SD. p. 157–163. Schwartz, H.F., Casciano, D.H., Asenga, J.A., and Wood, D.R. (1987). Field measurement of white mold effects upon dry beans with genetic resistance or upright plant architecture. Crop Science, 27: 699– 702. Schwartz, H.F., Steadman, J.R., and Coyne, D.P. (1978). Influence of Phaseolus vulgaris blossoming characteristics and canopy structure upon reaction to Sclerotinia sclerotiorum. Phytopathology, 68: 465– 470. Soltani, A., Bello, M., Mndolwa, E., Schroder, S., Moghaddam, S.M., Osorno, J.M., Miklas, P.N. and McClean, P.E. (2016). Targeted Analysis of Dry Bean Growth Habit: Interrelationship among Architectural, Phenological, and Yield Components. Crop Science, 56: 3005-3015. Soratto, R.P., Perez, A.A.G. and Fernandes, A.M. (2014). Age of No‐Till System and Nitrogen Management on Common Bean Nutrition and Yield. Agronomy Journal, 106: 809-820. Soratto, R.P., Fernandes, A.M., Pilon, C., Crusciol, C.A.C., and Borghi, E. (2013). Timing of nitrogen application on common bean cultivated after single corn or intercropped with palisade grass. (In Portuguese, with English abstract.). Pesqui. Agropecu. Bras., 48:1351– 1359. Stein, D. (2019). 2019 Custom machine and work rate estimates. East Lansing, MI: Michigan State University Extension. Retrieved from https://www.canr.msu.edu/isabella/uploads/files/2019%20MSU%20Custom%20Wo rk%20Rates.pdf Steinke, K., and Bauer, C. 2017. Enhanced efficiency fertilizer effects in Michigan sugarbeet production. Journal of Sugar Beet Research, 54, 2–19. Sulieman, S., Fischinger, S.A., Gresshoff, P. M., and Schulzea, J. (2013). Asparagine as a major factor in the N-feedback regulation of N2 fixation in Medicago truncatula. Physiologia Plantarum, vol. 140, no. 1, pp. 21–31. 142 USDA National Agricultural Statistics Service. (2020). USDA-NASS agricultural statistics 2020. USDA-NASS. http://www.nass.usda.gov Vitosh, M.L., Johnson, J.W., and Mengel, D.B. (1995). Tri-State fertilizer recommendations for corn, soybeans, wheat and alfalfa. E2567. East Lansing, MI: Michigan State University Extension. Warncke, D., & Brown, J. R. (2015). Potassium and other basic cations. In M. V. Nathan & R. Gelderman (Eds.), Recommended chemical soil test procedures for the North Central Region (pp. 71– 73). North Central Region Research Publication 221 (rev.). SB 1001. Columbia: Missouri Agricultural Experiment Station. Warncke, D., Dahl, J., and Jacobs, L. (2009). Nutrient recommendations for field crops in Michigan. Bulletin E2904, East Lansing, MI: Michigan State University Extension. Warncke, D., Robertson, L. S., & Mokma, D. (1980). Cation exchange capacity determination for acid and calcareous soils. In Agronomy abstracts (p. 147). Madison, WI: ASA. Westermann, D.T., Kleinkopf, G.E., Porter, L.K. and Leggett, G.E. (1981). Nitrogen Sources for Bean Seed Production. Agronomy Journal, 73: 660-664. Wolyn, D.J., D.A. St Clair, J. DuBois, J.C. Rosas, R.H. Burris, and F.A. Bliss. 1991. Distribution of nitrogen in common bean (Phaseolus vulgaris L.) genotypes selected for differences in nitrogen fixation ability. Plant Soil, 138:303–311. 143