lif‘r": : “ "r ->+-.. F E A .113? ~IOu-I—v—-v:’ ——'i i la... F¢~1A .F‘ 4-.-.‘I-I. ‘J;:j “av-'31...- l __0 0“ in ’f- i“! 4.“ '0‘" "ii-{I bilaéh.‘ This is to certify that the thesis entitled THE EFFECT OF PACKAGING MATERIAL AND STORAGE ON CORN SEED GERMINATION RATES presented by DONALD L . ABBOTT has been accepted towards fulfillment of the requirements for M.S. d . PACKAGING egree 1n fléw/U W T. w. Downes, . Major Mser Date May 5 , 1986 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution ‘DVIESI.J RETURNING MATERIALS: Place in book drop to LJBRARJES remove this checkout from u your record. F__I___NES will be charged if book is returned after the date stamped below. AUG ’. f7 J’I‘El THE EFFECT OF PACKAGING MATERIAL AND STORAGE ON CORN SEED GERMINATION RATES By Donald L. Abbott A THESIS Submitted To Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE SCHOOL OF PACKAGING 1986 ABSTRACT THE EFFECT OF PACKAGING MATERIAL AND STORAGE ON CORN SEED GERMINATION RATES By Donald L. Abbott Hybrid corn seeds with a 98% certified germination rate were pack— aged in four different packaging materials and stored for a period of 18 months (two storage seasons) in an unconditioned shelter and also under controlled high temperature and high humidity conditions. Samples were tested for moisture, headspace gases, and germination rates at three month intervals. After 12 months of uncontrolled storage, the seed ger- mination rates decreased and differences between the four packaging materials became apparent. The effect of package type on germination rates became more pronounced after 18 months. After 3 months of accel- erated storage, all seeds were dead and this part of the study was discontinued. After 18 months of storage, seed stored in plain paper bags decreased to 85.8% germination, seed in paper bags with a plastic inner liner decreased to 88.3% germination, seed in polyethylene bags decreased to 94.5% germination and seed in steel cans decreased to 96.5% germination. DEDICATION This thesis is dedicated to my parents, Gerald and Bertha Abbott. ii ACKNOWLEDGEMENTS I would like to express my sincere appreciation and gratitude to: Dr. Chester J. Mackson, Director, School of Packaging, for his faith in me and his insistence on the continuation of my education. Dr. Theron W. Downes, School of Packaging, for his professional wisdom and guidance which is an essential part of this thesis. Dr. Hugh E. Lockhart, School of Packaging, and Dr. Larry O. Copeland, Seed Specialist, Crop and Soil Science Department, for advice and service as committee members. The faculty and staff of the School of Packaging for their advice and support. Marjorie, my wife, and my children who made this thesis possible and worthwhile. iii TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES SYMBOLS AND TERMS INTRODUCTION LITERATURE REVIEW MATERIALS AND METHODS RESULTS DISCUSSION CONCLUSION RECOMMENDATIONS APPENDIX A. INITIAL SEED MOISTURE DATA APPENDIX B. HEADSPACE GAS DATA APPENDIX C. SEED MOISTURE DATA APPENDIX D. SEED GERMINATION DATA (WARM TEST) APPENDIX E. SEED GERMINATION DATA (COLD TEST) APPENDIX F. CALCULATION OF STANDARD DEVIATION APPENDIX G. CALCULATION OF SEED MOISTURE LIST OF REFERENCES iv Page vii viii 13 24 27 28 29 30 35 40 45 50 51 52 LIST OF TABLES Page TABLE 1. HEADSPACE CARBON DIOXIDE PERCENT. 15 TABLE 2. HEADSPACE OXYGEN PERCENT. 17 TABLE 3. SEED MOISTURE, GRAMS HZO/IOO GRAMS DRY MATERIAL/STANDARD DEVIATION. 19 TABLE 4. GERMINATION RATE (2) WITH STANDARD DEVIATION (WARM TEST). 22 TABLE 5. GERMINATION RATE (Z) WITH STANDARD DEVIATION (COLD TEST). 23 TABLE 6. INITIAL SEED MOISTURE DATA. 29 TABLE 7. HEADSPACE GAS DATA - PAPER BAGS. 30 TABLE 8. HEADSPACE GAS DATA PAPER WITH PLASTIC LINER BAGS. 32 TABLE 9. HEADSPACE GAS DATA - POLYETHYLENE BAGS. 33 TABLE 10. HEADSPACE GAS DATA - STEEL CANS. 34 TABLE 11. SEED MOISTURE DATA - PAPER BAGS. 35 TABLE 12. SEED MOISTURE DATA - PAPER/PLASTIC LINED BAGS. 37 TABLE 13. SEED MOISTURE DATA - POLYETHYLENE BAGS. 38 TABLE 14. SEED MOISTURE DATA - STEEL CANS. 39 TABLE 15. SEED GERMINATION DATA - WARM TEST - PAPER BAGS. 40 TABLE 16. SEED GERMINATION DATA — WARM TEST - PAPER/PLASTIC LINED BAGS. 42 TABLE 17. SEED GERMINATION DATA - WARM TEST - POLYETHYLENE BAGS. 43 TABLE 18. SEED GERMINATION DATA - WARM TEST - STEEL CANS. 44 TABLE 19. SEED GERMINATION DATA - COLD TEST - PAPER BAGS. 45 V TABLE 20. TABLE 21. TABLE 22. SEED GERMINATION DATA - COLD TEST - PAPER/PLASTIC LINED BAGS. 47 SEED GERMINATION DATA - COLD TEST - POLYETHYLENE BAGS. 48 SEED GERMINATION DATA - COLD TEST - STEEL CANS. 49 vi Figure Figure Figure Figure Figure Figure Figure LIST OF FIGURES Storage Container Seed Placement on Germination Paper Headspace Carbon Dioxide Headspace - Oxygen Seed Moisture, Grams HZO/IOO Grams Dry Material Seed Germination Rate (Warm Test) Seed Germination Rate (Cold Test) vii Page ll l4 16 20 21 SYMBOLS AND TERMS S.D. = Standard Deviation Plastic = Low Density Polyethylene Ave. = Average viii INTRODUCTION Corn is the only important cereal that evolved in the New World and is the leading cash crop in the United States (Chapman and Carter, 1976). It is the number one crap in the state of Michigan in both acre- age and dollar value (Erdmann et a1., 1981). Current United States' production is about. 80,000,000 acres ‘which. require about 25,000,000 bushels of seed that must be harvested, stored, and packaged for the next planting season which could be several years later. The amount of extra (contingency) seed produced, but not sold, to assure market avail- ability is unknown but significant. Much is written about general seed storage conditions (Justice and Bass, 1978). All agree low seed moisture and low storage temperatures are ideal. Some information is available on packaging material selec- tion (Copeland 1976), which shows moisture barrier materials are best, but most of these studies are based on small grass seeds and are in controlled environments. To date, nothing has been published about how the selection of a packaging material can influence hybrid corn seed stored in ambient conditions. Interest in this study was a result of having personal daily con- tact with both agriculture and commercial packaging. This study is restricted to the comparison of a specific commercial hybrid seed that was sealed in four different packaging systems and stored for 18 months (two planting seasons). Random samples of each packaging system were fully tested every three months for changes. The storage conditions selected for this study were those that might be found in an uncondi- tioned warehouse where daily temperature and relative humidity are constantly changing. Controlled storage conditions would have reduced seed deterioration but, from a commercial aspect, is costly and imprac— tical and was not considered for this study. For testing, selected samples were subjected to package headspace gas measurements, seed moisture, and cold and warm germination testing. Headspace gases measured were nitrogen, oxygen, and carbon dioxide, which would give an indication of seed respiration activity if the pack- aging material was of a suitable gas barrier. Only the steel cans had a measurable difference from normal atmospheric gas levels. Seed moisture gain or loss was measured to correlate seasonal humidity changes and packaging influences on seed protection. Seeds packaged in paper bags gained and lost significant moisture relative to seasonal relative humidity changes. Seeds packaged in paper bags with an inner plastic liner also gained or lost moisture, but to a lesser degree than did the paper only bags. Seeds in the plastic bags had a very small initial increase in moisture then remained quite stable for the remainder of the test period. Seeds packaged in steel cans did not show significant changes in moisture during this test period. Germination tests were conducted in accordance with "The Association of Official Seed Analysis Rules for Testing Seeds" and did show a germination difference corre- sponding to the different packaging materials. LIIERAIURE REVIEW Corn is a member of the grass family and is considered by many to be one of nature's most amazing energy storing devices. One small corn seed can turn into a 7 to 10 foot tall plant in just 9 weeks and some 8 weeks later will have produced up to 1,000 seeds (Aldrich, 1969). Delorit (1974) claims that corn is the most valuable crop grown in the United States and that half of the world's crop is grown here. Most of the crop goes into livestock feed for meat and dairy production and some poultry and egg production. About 9% is used for human consumption in a variety of ways. At least 95% of the corn grown is the "dent" type, which can be grown in every state except Alaska. It ranks second to wheat in acreage of field crops in the world. Annual seed require— ments for spring planting in the United States is about 2 million bags of 80,000 seeds each. Authors of seed technology and seed research are in general agree- ment on storage conditions of common seeds. All state that low storage temperature and low seed moisture are the most important factors in maintaining high germination rates. Cromarty (1982) classifies corn seed as "orthodox", where seed aging, which ultimately results in seed death, occurs as a function of time, temperature and moisture content. It is possible to influence the survival period by controlling the seed storage environment. The maxi- mum longevity of seeds can be realized by storage at a low temperature and moisture content (down to 5% moisture). COpeland (1976) states that this year's harvested seed crop would normally be planted 5 to 6 months later and the seeds are equipped to survive until the time and place are suitable for germination. Most species can survive storage much longer than one season when the proper conditions are available, but they cannot maintain viability indefi- nitely and will eventually deteriorate and die. The external factors that have the most influence on seed longevity are the relative humidity and temperature. He cites Harrington (1960) that the sum of the rela- tive humidity, in percentage, plus the temperature in Fahrenheit should not exceed 100 for safe storage. An R.H. above 752 will cause seed moistures to exceed 15%. Copeland (1976) further states that seeds of most species may be stored for several years by careful control of tem- perature and relative humidity but that such storage conditions are too costly for most agriculture seed lots such as corn and, as the seed deteriorates, one can expect delayed emergence, slower rates of seedling growth and development, decreased germination rates, and a decreased resistance to stress. Justice and Bass (1978) state that the purpose of storing seeds is to preserve planting stock from one season until the next and that there are advantages of carrying over seeds for two or more years to accom— modate low crop years and an unknown, changing demand. Seeds are physiologically mature when they attain maximum dry weight and from that point on they gradually lose vigor and eventually die. This life pro- cess can be manipulated but not stopped. They cite research as far back as 1832 that showed seed vitality would be prolonged if stored under conditions that would protect from heat, moisture, and oxygen. They agree that seed moisture content during storage is the most influential factor affecting their longevity. Normal seed respiration combines hexose with oxygen to give off carbon dioxide, water, and heat. This respiration can be reduced by keeping the seed dry and cool. Justice and Bass (1978) have found that storage for 3 to 5 years at ambient temperatures can be safely done in a sealed container after first drying the seeds to 5 - 8 percent moisture. Even longer storage can be expected if the seed moisture is reduced down 2 1/2 to 5 percent. The National Seed Storage Lab at Fort Collins, Colorado, stores most of their seed in sealed pint sized cans at a temperature of 4°C and an R.H. of 35%. Barton (1961) reports that corn seeds with a moisture content above 15% suffer severe damage at all temperatures and have even greater dam- age with fluctuating temeratures. Whitney (1980) has found that sensitive vegetable seeds can have a normally short storage lengthened to a guaranteed 3 years by packaging in a sealed aluminum/polyethylene laminate material and stored at 18°C, 25% R.H., but suggest that the procedure is not economically feasible for large quantities of common seeds. Bass and Clark (1967) reported that corn seeds maintained a 90% germination rate after 7 years of storage when the seed was dried to 10% moisture, sealed in a moisture-proof container and stored at 4°C and ambient R.H. For maximum longevity, seeds should be dried to 3—7% mois- ture sealed in moisture-proof containers and stored at -10°C. He says that, overall, seed moisture is the most critical factor in seed stor— age. This statement agrees with all other published reports. Treating corn seeds with a fungicide prior to storage does not reduce: germination rates and, according’ to Das et val. (1975), this treatment would generally result in a higher’ germination rate than untreated seeds. Seeds used for this study were treated with a fungi- cide. Justice and Bass (1978) state that several theories have been pro- posed on what causes a seed to deteriorate, none of which satisfactorily explain how seeds deteriorate. Even though the process of deterioration is not clearly understood, the methods for slowing it are well estab- lished. Other articles and books have been written on general seed storage and all agree with previously discussed findings. No publication could be found on studies of corn seed stored in various packaging materials in seasonal ambient conditions of fluctuating temperatures and relative humidity o 1. MATERIALS AND METHODS The following four packaging materials were studied: A. Four ply multi-wall stitched top and bottom paperbags. The three inner layers were unbleached kraft having a basis weight of 60 pounds and a thickness of 6 points. The outside layer was bleached kraft, having a basis weight of 60 pounds and a thick— ness of 7 points. Total surface area of the bag is 1,054 square inches. Seam to surface ratio was 1:29 (inch to inchz). Sur- face area per seed was .013 inZ/seed, 80,000 seeds per bag. Experimental bags were made from donated commercial bags that were cut down to make small bags measuring 6.5 inches by 5.25 inches which provided a total surface area of 68.25 square inches. Seam to surface ratio was 1:65 (inch to inchz). Sur- face area per seed was .114 inz/seed, 600 seeds per bag. Both top and bottom were closed by stitching with cotton thread to duplicate the commercial bags. Side seams were glued. Each testing period, six of these packages were removed to provide 24 warm germination tests and 24 cold germination tests. All other packages provided 12 samples of warm and cold germina- tion tests from 3 packages. B. Four ply multi-walled paper bags with a .7 mil layer of low den- sity polyethylene (LDPE) between layers 2 and 3. The three inner layers of paper ‘were unbleached kraft 'having :1 basis weight of 60 pounds and were 6 points thick. The outside layer was 60 pounds, 7 points bleached kraft and the buried PE was 0.7 mils. Total bag surface area is 1,054 square inches. Seam to surface ratio was 1:29 (inch to inchz). Surface area per seed was .013 inZ/seed. Test bags were cut down from full size commercial bags and measured 6.5 inches by 5.25 inches with a total surface area of 68.25 square inches. Seam to surface area ratio was 1:65 (inch to inchz). Surface area per seed is .114 inZ/seed, 600 seeds per bag. Both top and bottom were closed by stitching with cot- ton thread. The paper side seams were glued. The LDPE side seams were heat sealed. Two mil low density polyethylene tubes. These were made into heat sealed bags measuring 5.5 inches by 4 inches (flat) for a total surface area of 44 square inches. Surface area per seed was .073 in2/seed, 600 seeds per bag. Steel Cans. 302 x 408, exterior tinplate, interior enamel with a machine applied double seamed end. 3. 4. The test seed 'was 'hybrid corn, variety' number 2443, lot number 10,978 with a germination test date of 10-01-81 at 98%. These seeds were supplied by Great Lakes Hybrids, Inc., Ovid, Michigan. The storage container for all seeds stored under ambient conditions was made of wood framing and 1/4 inCh hardware cloth. It measured 48 x 33 x 26 inches. Its purpose was to protect from rodents and other pests that might cause damage to the test packages and seeds. The storage container had six layers of storage that provided for complete air circulation on all external surfaces (see Figure 1) of the test package. Separation of layers was provided by a frame with 4 inch wooden legs and a bed of 1 inch mesh chicken fencing. Each layer held 24 test packages proportioned from all four types of packages. Sampling consisted of removing 6 paper bags, 3 paper/LDPE bags, 3 LDPE bags and 3 steel cans at 3 month intervals without dis- turbing the remaining samples. Accelerated Storage. Accelerated storage testing was done in a high temperature (100°F), high humidity (85%) environment for the purpose of accelerating the seed's deterioration rate, which allows a shelf life determination in a shortened time period. This testing was conducted in a Michigan State University walk-in, controlled envi- ronmental room (Lab-Line Instrument Inc.). 10 Fig. 1. Storage Container. Germination Paper. Standard commercially available germination paper was used for the seed bed in accordance with "The Association of Official Seed Analysts Rules for Testing Seeds". Both warm and cold testing was conducted. All seed was placed on the moistened germination paper, 100 seeds per paper, in 2 groups of 50 for ease of counting and statistical analysis (see Figure 2). Cold test samples were stored at 10°C for 7 days prior to testing. Both warm and cold test samples were placed in 25°C germination chambers at the Michigan Crop Improvement Association Laboratory. After seven days, each seed was studied for abnormal or normal germination and recorded as percent germinated. Details of seed germination testing may be found in above cited rules for testing. 11 Fig. 2. Seed Placement on Germination Paper. Scales. All weight measurements were performed with a Mettler P1000 standard platform scale capable of measuring to .01 grams, and a Mettler AE160 capable of measuring to .0001 grams. Headspace Gases. Headspace gases of oxygen, carbon dioxide, and nitrogen were measured by a Carle GC8700 gas chromatograph with a Porapak Q column. Gas peaks were recorded on a Heath—Zenith strip chart recorder model SR204. Initial Mbisture Determination. Initial seed moisture was measured in accordance with AOAC (Methods of Analysis of the Association of 12 Official Analytical Chemists). Sample seed was ground up using a number 20 sieve, weighed on a Mettler balance, and placed in a vacuum oven. The vacuum system was a Michigan State University, Welch Duo Seal Vacuum pump model 1400, and a National Appliance Company Model 583 vacuum oven. Drying conditions were 100°C with a pressure equivalent of approximately 25 mmHg for 5 hours. Con- trolled cooling was in a standard laboratory desiccator. RESULTS Experiments were carried out according to previously described pro- cedures. Results are shown in Figures 3-7 and in Tables 1-22. Figure 3 shows that headspace CO2 changed in the steel cans, all others were unchanged. Figure 4 shows that headspace oxygen decreased in the steel cans with a small decrease in the plastic bag. All others were unchanged. Figure 55 Shows the seasonal affect changing relative humidity has on the test seed. Figure 6 shows the packaged seed germination deterioration over time (warm test). Figure 7 shows the packaged seed germination deterioration over time (cold test). 13 Percent Carbon Dioxide 0.28 0.24 0.20 0.16 0.12 0.08 0.04 14 Paper Bags Paper with Plastic Liner Bags Plastic Bags .UDO Steel Cans l L J O 3 6 9 12 15 18 Months Fig. 3. Headspace Carbon Dioxide. 15 TABLE 1. HEADSPACE CARBON DIOXIDE PERCENT. Time Paper Paper/Plastic Plastic Steel (Months) 32321. Lined Bags Bags 52531. 3 .03 .03 .03 .03 6 .03 .03 .03 .06 9 .03 .03 .03 .07 12 .03 .03 .03 .09 15 .03 .03 .03 .16 18 .03 .03 .03 .20 Percent Oxygen 22 21‘ 20 19 l8 l7 16 15 16 CDC» EDD EDD CF----CD I] C O 0 Paper Bags A Paper with Plastic Lined Bags [3 ‘Plastic Bags II Steel Cans l J I l r l J 3 6 9 12 15 18 Months Fig. 4. Headspace Oxygen. 17 TABLE 2. HEADSRACE OXYGEN PERCENT Time Paper Paper/Plastic Plastic Steel (Months) Bags Lined Bags Bags £323:_ 3 21 21 21 21 6 21 21 21 21 9 21 21 21 20 12 21 21 21 20 15 21 21 21 19 18 21 21 20 19 Seed Moisture, g/100 g Dry Material l8 l8r (D 17 * \ C) C) 15 r A £3 £5 E] 14 - 9 o 1.1 0 Paper Bags A Paper Bagswith Plastic Liner O 12_ [3 Plastic Bags . Steel Cans 11 L l A l l I 3 6 9 12 15 18 Months Fig. 5. Seed Moisture, Grams H20/100 Grams Dry Material. ‘0 TABLE 3. SEED MOISTURE, GRAMS HZOIIOO exams DR! MATERIAL/STANDARD DEVIATION. Time Paper (Months) i§E§L_ 3 16.39/.3 6 13.26/.1 9 15.27/.62 12 17.24/.64 15 16.69/.28 18 12.34/.13 19 Paper/Plastic Plastic Lined Bags Bags 14.53/.03 14.22/.O3 14.08/.13 14.23/.03 15.16/.03 14.48/.03 15.90/.04 14.38/.26 15.82/.67 14.71/.07 14.99/.03 14.63/.03 Steel Cans 13.74/.05 13.69/.01 13.59/.02 13.59/.09 13.69/.O7 13.62/.17 Percent Germination 20 100 ’ U 5 g B? % \ \o A A F U D o :1 \. A 1:] 95 t O 90 ‘ 0 Paper Bags [5 Paper with Plastic Liner Bags ‘3 L E] Plastic Bags . Steel Cans O 235 L i L l I L A A O 3 6 9 12 15 18 Months Fig. 6. Seed Germination Rate (Warm Test) Percent Germination 100 90' 80 70 60 50 40 30 20 10 O uh ob 21 O D t (3 Paper Bags 45 Paper with Plastic Liner Bags [3 Plastic Bags t . Steel Cans 9 1 Months NP |_1 Ln 1“ 00 Fig. 7. Seed Germination Rate (Cold Test). 22 TABLE 4. GERMINATION RATE (1) WITH STANDARD DEVIATION (WARM TEST). Time Paper With (Months) Paper Bags Plastic Liner Plastic Bags Steel Cans 3 98.50 i 1.59 98.08 i 1.24 98.58 t 1.16 99.00 t 0.95 6 98.75 t 1.85 98.83 i 1.34 98.83 t 1.99 99.00 t 1.35 9 99.17 i 1.31 99.50 i 0.90 97.00 i 2.49 99.50 t 0.90 12 97.00 i 2.89 97.83 i 2.62 97.50 t 2.84 99.33 i 0.93 15 93.42 i 3.36 95.67 i 2.33 97.00 t 2.76 99.00 t 1.60 18 85.83 i 6.46 88.33 t 2.93 94.50 t 3.09 96.50 t 2.71 23 Paper With Plastic Liner Plastic Bags TABLE 5. Time (Months) Paper Bags 3 98.29 t 2.01 6 Destroyed 9 Destroyed 12 91.33 t 5.52 15 6.46 i 4.13 18 4.50 i 2.72 98.25 i 1.29 100.00 1 0.00 95.33 i 4.77 95.17 t 2.62 17.17 t 8.38 9.00 t 4.47 99.25 t 0.75 100.00 t 0.00 98.50 i 1.51 93.83 t 4.71 48.17 1 19.00 9.17 t 2.48 GERMINATION RATE (1) WITH STANDARD DEVIATION (COLD TEST). Steel Cans 99.08 t 0.90 100.00 t 0.00 96.83 t 3.46 97.83 t 1.99 63.67 t 11.05 13.33 t 4.38 Rh fit to Res 1'96 and Seed Dani cond at t] facto DISCUSSION Justice and Bass (1978) and others have stated that storage temper- ature and seed moisture content are the most important factors affecting seed longevity, with seed moisture content usually more influential than temperatures. Copeland (1976) cited studies of grass seed packaged in various 'materials that showed the better' moisture barrier ‘materials maintained a higher seed germination rate. The results of this study support published data of general seed storage research. This study does concentrate on a specific species of hybrid corn seed and a specific hybrid out of many hybrid corn seeds. What was found to be true for this particular seed may not apply speci- fically to other hybrid corn seeds found throughout the world and indeed to other hybrids from the same grower where these seeds were obtained. Research by previously cited authors suggests that all corn seeds would react to packaging in a similar manner. Justice and Bass (1978) point out that many other factors, suCh as mechanical damage during harvest and handling, seed maturity at harvest, and other problems do influence seed longevity. This study is directed to the problems of the seed com- panies, the distributors, and the farmers that have uncontrolled storage conditions and are interested in having an acceptable germination rate at the time of planting. Once the research seeds were packaged and put into storage only the factors of seed temperature and seed moisture content influenced natural 24 25 aging of the seed. Harrington (1972) states that each 5°C increase in seed storage temperature will reduce the seed life by about half. Dur- ing this study, which extended over two Michigan winters, the ambient storage temperature varied from a low of -10°C to +35°C with many fluc- tuations between extremes. According to Harrington (1972), this temperature change did harm the seed. This study recognizes the impor- tance of temperature control but is restricted to relative humidity influence and how the packaging material might extend the shelf life of a specific corn seed. Headspace gases were monitored throughout the study period and were found to have measurable changes only where they were fully contained by the package. Only the steel can had a significant change in carbon dioxide and oxygen. All other packaging materials have a gas permeation rate that allowed headspace gases to be in equilibrium with the atmos- phere. Figures 3 and 4, in the Results Section, shows the steel can's ability to retain gases. Figure 5 in the Results Section deals with measurement of moisture in the seed. Moisture changes are influenced by the packaging material's water ‘vapor transmission. rate. Harrington (1960) states, as a ”rule of thumb”, that the life of a seed is halved for each 5°C increase. in. seed storage temperature and for‘ each. 1% increase in seed moisture content. Combining Figures 5, 6, and 7 in the Results Section shows some correlation and generally supports the work of Harrington (1960) and others in seed storage. A warm and a cold seed germination test was conducted in accordance with ”The Association of Official Seed Analysts Rules for Testing Seeds". 26 The warm germination test is a measure of seed viability or the ability to produce a normal seedling. This test is accomplished by pla- cing a quantity of seed between moistened germination paper that is then rolled up in a protective layer of wax paper and placed in a 25°C germi- nation chamber for seven days. .After seven days the seed is observed for normal and abnormal seedlings. The Michigan Seed Foundation requires a minimum of 90% normal seed germination for certification. Only warm germination results are recorded on the seed data card. The cold germination test is conducted to measure seedling vigor. This test is not required by the Michigan Seed Foundation. This test is started the same as for warm testing except 1 cm of moist soil is placed over the seed before rolling the paper up. The rolled up seed is then placed in a cold chamber (10°C) for seven days followed by the warm (25°C) germination chamber for seven days. Evaluation is the same as in the warm test and measures a seed's ability to overcome stress before regular germination. The Michigan Seed Foundation states that a good seed should have a cold test of 75% germination or better, but is a mea— sure of seed vigor and is not recorded on the seed data card for certification. Statistical analysis of seed germination rates does not identify any significant difference of the packaging materials' protective abil- ity until the 15th and 18th month of storage. At the 18th month of storage, seeds in the steel can and the plastic bag tested well above the 90% germination minimum for certification and could have been sold as certified seed. The paper and paper/plastic bags were well below minimum certification and could not have been sold as certified seed. CONCLUSION Packaging material does have a significant influence on stored corn seed germination rates. The steel can, (u: containers of equally high impermeability properties, provides the best protection of stored seed but they are not economically practicable for large quantities of agri- cultural seeds. Multiwall paper bags serve the function of containing and handling bushel size seed packages, but do not provide any protection from cli- matic conditions. The inclusion of a thin layer of plastic in the multiwall paper bags does increase the protection to the seed slightly, but stitch closing and lack of heat sealing of the top and bottom reduces the potential protection qualities of the plastic. Low density polyethylene bags provide significant protection from moisture and do a good job of maintaining germination rates and thus extending the shelf life of corn seeds. Seed stored in the steel cans and the sealed plastic bags passed the warm germination test for certified seed after 18 months of storage. Paper based packages could not have been certified after 18 months of storage. 27 RECOMMENDATIONS The research conducted for this study suggests that if commercial corn seed companies switched from the traditional multiwall paper bags no.a 4 mil low density polyethylene bag they would increase the shelf life of their product. Current cost of a 4 mil LDPE bag measuring 16” x 28" is $0.1318, while a comparable size 4-ply multiwall bag costs $0.23. Therefore, the cost of switching to plastic packaging material should be a plus factor. Moisture protection from a permeation point will be twice as good (4 mil vs. 2 mil) as the material studied in the research. Also, the seed to packaging material area will be reduced from .073 in2 2 per seed in the test bag to .013 in per seed in the commercial size bag, which significantly reduces (82%) the amount of permeating moisture per seed. Graphics should not be a problem on LDPE bags. If necessary, a layer of quality printing paper could easily be laminated to the plastic with little increase in cost. Switching from paper bags to polyethylene bags will result in reducing packaging costs and extending the shelf life of corn seeds and should be considered by commercial seed compan- ies. 28 APPENDIX A INITIAL S- MOISTURE DATA APPENDIX A INITIAL SEED MOISTURE DATA TABLE 6. INITIAL SEED MOISTURE DATA. Date Sample Initial Weight Final Weight Percent H22_ 1-4-82 1 2.0200 g 1.7668 g 12.5347 2 2.0000 g 1.7490 g 12.5500 3 2.0021 g 1.7518 g 12.5019 Average Moisture = 12.5287% g H20/100 g dry matter = 14.3235 g Standard Deviation* = 0.02 *See Appendix F for moisture formula. 29 APPENDIX B HEADSPACE GAS DATA APPENDIX B HEADSPACE GAS DATA TABLE 7. NEADSPACE GAS DATA - PAPER BAGS. Package Batch Batch Date Code % C02 Average % 02 Average 3-21-82 PlR .03 21.0 P4R .03 21.0 PSR .03 21.0 P6R .03 21.0 P7R .03 21.0 P8R .03 .03 21.0 21.0 7-01-82 P2R .03 21.0 P3R .03 21.0 P9R .03 21.0 P10R .03 21.0 PllR .03 21.0 P12R .03 .03 21.0 21.0 9-22-82 P13R .03 21.0 P14R .03 21.0 P15R .03 21.0 P16R .03 21.0 P23R .03 21.0 P24R .03 .03 21.0 21.0 12-15-82 P17R .03 21.0 P18R .03 21.0 P19R .03 21.0 P20R .03 21.0 P21R .03 21.0 P22R .03 .03 21.0 21.0 3~20-83 P27R .03 21.0 P28R .03 21.0 P29R .03 21.0 P30R .03 21.0 P31R .03 21.0 P32R .03 .03 21.0 21.0 30 31 TABLE 7 (Continued) Package Batch Batch Date Code % CO2 Average % 02 Average 6-15-83 P26R .03 21.0 P36R .03 21.0 P37R .03 21.0 P38R .03 21.0 P39R .03 21.0 P40R .03 .03 21.0 21.0 32 TABLE 8. HEADSPACE GAS DATA - PAPER WITH PLASTIC LINER BAGS. Package Batch Batch Date Code % C02 Average % 02 Average 3-21-82 PP2R .03 21.0 PP3R .03 21.0 PPlR .03 .03 21.0 21.0 PP5R .03 21.0 PP9R .03 .03 21.0 21.0 9-22-82 PP6R .03 21.0 PP7R .03 21.0 PPIOR .03 .03 21.0 21.0 PP12R .03 21.0 PPISR .03 .03 21.0 21.0 3-20-83 PPllR .03 21.0 PP13R .03 21.0 PP14R .03 .03 21.0 21.0 6-15-83 PP17R .03 21.0 PP18R .03 21.0 PP19R .03 .03 21.0 21.0 33 TABLE 9. HEADSPACE GAS DATA - POLYETHYLENE BAGS. Package Batch Batch Date Code % CO2 Average % 02 Average 3-21-82 PE4R .03 21.0 PESR .03 21.0 PE6R .03 .03 21.0 21.0 7-01-82 PEIR .03 20.8 PE2R .03 20.8 PE3R .03 .03 20.8 20.8 S.D. ‘3 000 9-22-82 PE7R .03 20.8 PE8R .03 20.8 PE9R .03 .03 21.0 20.9 S.D. = 0010 12—15-82 PE15R .03 21.0 PE16R .03 21.0 PE17R .03 .03 21.0 21.0 3-20—83 PEIOR .03 21.0 PEllR .03 21.0 PE12R .03 .03 21.0 21.0 6-15—83 PE13R .03 20.0 PE14R .03 20.4 PE23R .03 .03 20.4 20.3 S.D. - 0020 34 TABLE 10. HEADSPACE GAS DATA - STEEL CANS. Package Batch Batch Date Code % CO2 Average % 02 Average 3-21-82 SC2R .03 21.0 SC3R .03 21.0 SC4R .03 .03 21.0 21.0 SC5R .06 21.0 SC6R .06 .06 21.0 21.0 9-22-82 SC8R .08 20.0 SC1OR .08 20.0 SCllR .08 .08 20.0 20.0 12-15-82 SC7R .03 20.0 SC9R .04 20.0 SC12R .04 .04 20.0 20.0 SODO=00054 SC14R .16 19.0 SC16R .17 .17 19.7 19.4 SeDo=oOO8 S.D. = 029 6-15-83 SC15R .19 19.6 SC19R .19 19.3 SCZOR .21 .20 19.5 19.5 S.D03001 SOD. = 012 APPENDIX C SEED MOISTURE DATA APPENDIX C SEED MOISTURE DATA TABLE 11. SEED MOISTURE DATA - PAPER BAGS. Initial Final 35 Package weight Weight g H20/100 g Batch Date Code (g) (g) Dry Matter Average S.D. 3-21-82 PlR 201.2 204.3 16.09 P4R 204.3 208.4 16.62 PSR 218.9 222.8 16.36 P6R 188.4 191.9 16.45 P7R 203.4 207.8 16.80 P8R 200.8 203.8 16.03 16.39 0.30 7-01-82 P2R 199.5 197.6 13.24 P3R 199.3 197.6 13.35 P9R 201.8 199.9 13.25 P10R 194.1 192.4 13.32 P11R 201.5 199.3 13.08 P12R 200.6 198.8 13.30 13.26 0.10 9-22-82 P13R 192.9 195.1 15.63 P14R 204.2 206.8 15.78 P15R 195.9 198.5 15.84 P16R 199.2 200.9 15.30 P23R 196.6 197.3 14.73 P24R 200.5 200.5 14.32 15.27 0.62 12-15-82 P17R 212.4 218.3 17.50 P18R 204.4 210.2 17.57 P19R 199.3 204.6 17.37 P20R 208.2 213.7 17.35 P21R 204.0 210.0 17.69 P22R 197.3 200.1 15.95 17.24 0.64 3-20-83 P27R 203.6 208.0 16.80 P28R 192.5 196.2 16.52 P29R 204.4 208.4 16.56 P30R 204.5 209.3 17.01 P31R 203.0 206.5 16.30 P32R 203.3 208.0 16.97 16.69 0.28 Date 6-15-83 36 TABLE 11 (Continued) Initial Package Weight Code (g) P26R 196.6 P36R 194.6 P37R 200.8 P38R 202.4 P39R 196.0 P40R 207.4 Final Weight. g H20/100 g Batch (g) Dry Matter Average S.D. 193.3 12.41 191.3 12.39 197.3 12.33 199.2 12.52 192.5 12.28 203.4 12.12 12.34 0.13 37 TABLE 12. SEED MOISTURE DATA - PAPER/PLASTIC LINED BAGS. Initial Final Package Weight Weight g H20/100 g Batch Date Code (g) (g) Dry Matter Average S.D. 3-21-82 PP2R 200.6 201.0 14.55 PP3R 200.7 201.1 14.55 PPlR 201.8 202.1 14.49 14.53 0.03 7—01-82 PP4R 201.4 201.1 14.15 PPSR 199.8 199.5 14.15 PP9R 200.5 199.8 13.93 14.08 0.13 9-22-82 PP6R 200.3 201.8 15.18 PP7R 199.9 201.4 15.18 PP10R 200.4 201.8 15.12 15.16 0.03 12-15-82 PP8R 200.1 202.9 15.92 PP12R 200.3 203.1 15.92 PP15R 200.8 203.5 15.86 15.90 0.04 3-20-83 PPllR 200.5 204.0 16.32 PP13R 201.5 204.6 16.08 PP14R 200.2 201.5 15.07 15.82 0.67 6-15-83 PP17R 200.6 201.8 15.01 PP18R 200.0 201.2 15.01 PP19R 200.8 201.9 14.95 14.99 0.03 38 TABLE 13. SEED MOISTURE DATA - POLYETHYLENE BAGS. Initial Final Package Weight Weight. g H20/100 g Batch Date Code (g) (g) Dry Matter Average S.D. 3-21-82 PE4R 200.0 199.9 14.27 PESR 200.2 200.0 14.21 PE6R 200.0 199.8 14.21 14.22 0.03 7-01-82 PElR 200.4 200.2 14.21 PE2R 200.2 200.1 14.27 PE3R 200.5 200.3 14.21 14.23 0.03 9-12-82 PE7R 200.3 200.6 14.50 PE8R 200.2 200.5 14.50 PE9R 200.3 200.5 14.44 14.48 0.03 12—15-82 PEISR 200.3 200.8 14.61 PE16R 200.3 200.5 14.44 PE17R 200.0 199.6 14.10 14.38 0.26 PEllR 200.5 201.1 14.67 PE12R 200.1 200.7 14.67 14.71 0.07 6-15-83 PE13R 200.2 200.8 14.67 PE14R 200.2 200.7 14.61 PE23R 199.9 200.4 14.61 14.63 0.03 39 TABLE 14. SEED MOISTURE DATA.- STEEL CANS. Initial Final Package Weight Weight g H20/100 g Batch Date Code (g) (g) Dry Matter Average S.D. 3-21-82 SCZR 254.2 252.9 13.74 SC3R 251.5 250.1 13.69 SC4R 259.5 258.3 13.80 13.74 0.05 SCSR 247.4 246.0 13.68 SC6R 256.1 254.7 13.70 13.69 0.01 9-12-82 SC8R 249.0 247.4 13.59 SC10R 241.4 239.8 13.57 SC11R 254.1 252.5 13.61 13.59 0.02 12-15-82 SC7R 245.2 243.5 13.53 SC9R 250.3 248.6 13.55 SC12R 257.8 256.4 13.70 13.59 0.09 3-20-83 SC13R 256.4 255.0 13.70 SC14R 256.5 254.9 13.61 SC16R 256.0 254.7 13.74 13.69 0.07 6-15-83 SC15R 250.6 249.0 13.59 SC19R 253.7 251.8 13.47 SC20R 243.1 242.0 13.81 13.62 0.17 APPENDIX D SEED GERMINATION DATA (WARM TEST) APPENDIX D SEED GERMINATION DATA.(WARM TEST) TABLE 15. SEED GERMINATION DATA - WARM TEST - PAPER BAGS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 PlR 95 - 99 - 96 - 100 P4R 98 - 96 - 99 - 99 P5R 99 - 96 - 100 - 100 P6R 98 - 98 - 99 - 96 P7R 98 - 100 - 100 - 100 P8R 99 - 99 - 100 - 100 98.5 1.59 7-01-82 P2R 100 - 100 - 98 - 94 P3R 100 - 100 - 96 - 100 P9R 98 - 96 - 96 - 100 P10R 100 - 100 - 96 - 100 P11R 100 - 100 - 100 - 100 P12R 100 - 98 - 98 - 100 98.6 1.85 9-22-82 P13R 98 - 100 - 100 - 98 P14R 100 - 98 - 100 - 100 P15R 100 - 98 - 100 — 98 P16R 100 - 100 - 96 - 100 P23R 96 — 100 - 100 - 98 P24R 100 - 100 - 100 - 100 99.2 1.31 12-15-82 P17R 98 - 98 - 92 - 96 P18R 98 - 100 - 94 - 94 P19R 100 - 100 — 96 - 96 P20R 100 - 98 - 98 - 98 P21R 98 - 100 - 96 - 100 P22R 92 - 100 - 90 - 96 97.0 2.89 3-20-83 P27R 100 - 90 - 90 - 92 P28R 98 - 98 - 98 - 88 P29R 92 - 90 - 94 - 96 P30R 9O - 90 - 90 - 96 P31R 94 - 94 - 92 - 92 P32R 92 - 92 - 96 - 98 93.4 3.36 40 Date 6-15-83 41 TABLE 15 (Continued) Package Batch Code Germination % Average P26R 86 - 94 - 94 - 96 P36R 84 - 80 - 76 - 74 P37R 88 - 8O - 92 - 76 P38R 90 - 84 - 92 - 76 P39R 92 - 90 - 92 - 88 P40R 86 - 84 — 82 - 84 85.8 Standard Deviation 6.46 42 TABLE 16. SEED GERMINATION DATA.- NARM.TEST - PAPER/PLASTIC LINED BAGS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 PP2R 97 - 96 - 98 - 97 PP3R 97 - 100 - 100 - 98 PPlR 98 - 99 - 99 - 98 98.1 1.24 7-01-82 PP4R 100 - 98 - 98 - 100 PPSR 96 - 100 - 98 - 98 PP9R 100 - 100 - 98 - 100 98.8 1.34 9-22-82 PP6R 100 - 98 - 100 - 100 PP7R 100 - 98 - 100 - 98 PPIOR 100 - 100 - 100 - 100 99.5 0.90 12-15-82 PP8R 100 - 100 - 98 - 100 PP12R 98 - 94 - 94 - 94 PP15R 96 - 100 - 100 ~ 100 97.8 2.62 3-20-83 PPllR 94 - 94 - 96 - 94 PP13R 94 - 94 - 98 - 98 PP14R 100 - 94 - 98 - 94 95.7 2.23 6-15-83 PP17R 96 - 86 - 90 - 88 PP18R 86 - 90 - 88 - 86 PP19R 86 - 86 - 88 - 90 88.3 2.93 TABLE 17. Date 3-21-82 7-01-82 9-22-82 12-15-82 3-20-83 6-15-83 43 SEED GERMINATION DATA - WARM TEST - POLYETHYLENE BAGS. Package Code PE4R PESR PE6R PElR PE2R PE3R PE7R PE8R PE9R PE15R PE16R PE17R PE10R PEllR PE12R PE13R PE14R PE23R 98 98 98 100 96 100 100 96 92 92 92 100 94 100 96 96 88 92 Germination - 100 96 - 98 98 - 99 99 - 100 98 - 100 100 - 100 94 - 100 94 - 98 98 - 96 98 - 100 98 - 98 96 - 100 98 - 100 98 - 92 100 - 94 100 - 98 94 - 98 98 96 100 99 100 98 100 100 100 96 96 98 98 100 98 96 96 92 94 96 Batch Average 98.6 98.8 97.0 97.5 97.0 94.5 Standard Deviation 1.16 1.99 2.49 2.84 2.76 3.09 44 TABLE 18. SEED GERMINATION DATA - HARM TEST - STEEL CANS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 SC2R 98 - 99 - 97 - 99 SC3R 99 - 100 - 99 - 100 SC4R 100 - 100 - 99 - 98 99.0 0.95 7-01-82 SC1R 100 - 100 - 100 - 100 SCSR 96 - 100 - 98 - 100 SC6R 98 - 98 - 98 - 100 99.0 1.35 9-22-82 SC8R 100 - 100 - 98 - 98 SC10R 100 - 100 - 100 - 98 SC11R 100 - 100 - 100 - 100 99.5 0.90 12-15—82 SC7R 100 - 100 - 98 - 100 SC9R 98 - 100 - 98 - 100 SC12R 98 - 100 - 100 - 100 99.3 0.98 3-20-83 SC13R 100 - 100 - 100 - 100 SC14R 100 - 96 - 98 - 100 SCl6R 96 - 100 - 98 - 100 99.0 1.60 6-15-83 SC15R 92 - 96 - 100 - 98 SC19R 92 - 98 - 98 - 96 SC20R 100 - 98 - 94 - 96 96.5 2.71 APPENDIX E SEED GERMINATION DATA (COLD TEST) APPENDIX E SEED GERMINATION DATE (COLD TEST) TABLE 19. SEED GERMINATION DATA - COLD TEST - PAPER BAGS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 PlR 98 - 96 - 98 - 95 P4R 96 - 96 - 95 - 94 PSR 97 - 100 - 97 - 99 P6R 100 - 100 - 99 - 100 P7R 99 - 100 - 100 - 100 P8R 100 - 100 - 100 - 100 98.3 2.01 7~01~82 PZR P3R P9R THIS BATCH CONTAMINATED P10R N0 GERMINATION PllR P12R 9-22-82 P13R P14R P15R THIS BATCH CONTAMINATED P16R N0 GERMINATION P23R P24R 12-15-82 P17R 90 - 88 - 80 - 84 P18R 96 - 98 - 88 - 92 P19R 96 - 96 - 92 - 90 P20R 86 - 88 - 80 - 88 P21R 86 - 96 - 96 - 96 P22R 96 - 96 - 96 - 98 91.3 5.52 3-20-83 P27R 8 - 6 - 4 - 4 P28R 6 - 4 - 4 - 0 P29R 6 - 0 - 8 - 12 P3OR 16 - 14 - 12 - 12 P31R 8 - 4 - 4 - 6 P32R 4 - 4 - 6 - 4 6.5 4.13 45 Date 6-15-83 Package Code P26R P36R P37R P38R P39R P40R 46 TABLE 19 (Continued) Batch Germination % Average 8 - 4 - 6 - 6 2 - 2 - 4 - 6 0 - 6 - 4 - 6 4 - 6 - 8 - 8 2 - 8 - 2 - 2 0 - 6 - 0 - 8 4.5 Standard Deviation 2.72 47 TABLE 20. SEED GERMINATION DATA - COLD TEST - PAPER/PLASTIC LINED BAGS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 PP2R 99 - 99 - 98 - 100 PP3R 99 - 98 - 97 - 96 PPlR 99 - 99 - 99 - 96 98.3 1.29 7-01-82 PP4R 100 - 100 - 100 - 100 PPSR DESTROYED PP9R 100 - 100 - 100 - 100 100.0 0.00 9-22-82 PP6R 82 - 96 - 100 - 96 PP7R 96 - 98 - 96 - 100 PP10R 96 - 92 - 94 — 98 95.3 4.77 12-15-82 PP8R 94 - 96 - 96 - 98 PP12R 100 ~ 96 - 92 - 96 PP15R 96 - 94 - 90 - 94 95.2 2.62 3-20-83 PPllR 10 ~ 6 ~ 26 ~ 20 PP13R 10 - 6 - 30 - 26 PP14R 16 - 26 - 14 - 16 17.2 8.38 6-15-83 PP17R 6 - 10 - 8 - 10 PP18R 2 - 4 - 10 - 8 PP19R 10 - 8 - 12 - 20 9.0 4.47 48 TABLE 21. SEED GERMINATION DATA - COLD TEST - POLTETHYLENE BAGS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 PE4R 100 - 98 - 99 - 98 PESR 100 - 100 - 100 - 99 PE6R 99 - 99 - 99 - 100 99.3 0.75 7-01-82 PElR 100 - 100 - 100 - 100 PE2R 100 - 100 - 100 - 100 PE3R 100 - 100 - 100 - 100 100.0 0.00 9-22-82 PE7R 98 - 98 - 100 - 98 PE8R 100 - 100 - 96 - 100 PE9R 98 - 96 - 98 - 100 98.5 1.51 12-15-82 PE15R 96 - 98 - 92 - 92 PE16R 96 - 96 - 88 - 98 PE17R 82 - 96 - 96 - 96 93.8 4.71 3-20-83 PEIOR 18 - 26 - 56 - 28 PEllR 60 - 62 - 64 - 24 6-15-83 PE13R 6 - 12 - 10 - 10 PE14R 8 - 8 - 4 - 10 PE23R 12 - 10 - 8 - 12 9.2 2.48 49 TABLE 22. SEED GERMHNATION DATA - COLD TEST - STEEL CANS. Package Batch Standard Date Code Germination % Average Deviation 3-21-82 SC2R 99 - 98 - 100 - 100 SC3R 100 - 100 - 98 - 100 SC4R 98 - 99 - 99 - 98 99.1 0.90 7-01-82 SC1R 100 - 100 - 100 - 100 SC5R 100 - 100 - 100 - 100 SC6R 100 - 100 - 100 - 100 100.0 0.00 9-22-82 SC8R 100 - 96 - 100 - 88 SC10R 98 - 100 - 98 - 100 SCllR . 96 - 96 - 94 - 96 96.8 3.46 12-15-82 SC7R 96 - 100 - 100 - 100 SC9R 100 - 98 - 98 — 96 SC12R 94 - 98 - 96 - 98 97.8 1.99 3-20-83 SC13R 60 - 66 - 72 - 70 SC14R 70 - 60 - 56 - 80 SC16R 50 - 52 - 80 - 48 63.7 11.05 6-15-83 SC15R 12 - 14 - 14 - 20 SC19R 8 - 6 - 14 - 12 SCZOR 14 - 22 - 12 - 12 13.3 4.38 APPENDIX B CALCULATION OF STANDARD DEVIATION APPENDIX P CALCULATION OF STANDARD DEVIATION \jl (x-u)2| n - 1 SOD. 8 U) 0 U o 11 Standard Deviation M 11 Sum of measured data Measured data >4 It Mean of the measurements T: 11 n = Number of measurements 50 APPENDIX C CALCULATION OF SEED MOISTURE APPENDIX C CALCULATION OF SEED MOISTURE WF - (Wo x 0.8747) 100 = g H20/100 g dry matter Wo x 0.8747 WF = Final corn sample weight Wo = Original corn sample weight 0.8747 = Original dry matter weight of 1 gram of corn seed 51 LIST OF REFERENCES LIST OF REFERENCES Aldrich, S.R. and Leng, E.R. 1969. Modern Corn Production. F & W Publishing Corp., Cincinnati, OH. AOAC. 1980. Official Methods of Analysis, 13th Ed. Association of Official Analytical Chemists, Washinton, DC. Bass, L.N. and Clark, D.C. 1967. Varietal Difference in Longevity of Vegetable Seed and Their Response to Various Storage Conditions. Proceedings, American Society Horticulture Science. 91:521. Barton, L.V. 1961. Seed Preservation and Longevity. Interscience Publishers, NY. Bender, F.E., Douglas, L.W. and Kramer, A. 1982. Statistical Methods for Food and Agriculture. AVI, Connecticut. Bockhart, A.S., Rogers, J.S. and Richmond, T.R. 1969. Effects of Various Storage Conditions on Longevity of Cotton, Corn and Sorghum Seeds. Crop Science, Vol. 9, March-April 1969. Brooker, D., Bakker-Arkema, F. and Hall, C. 1974. Drying Cereal Grains, 3rd printing, 1981. AVI Publishing company, Westport, CT. Canode, C.L. 1972. Germination of Grass Seeds as Influenced by Storage Conditions. Crop Science. Jan.—Feb. 1972, 79:80. Cavers, P.B. 1974. Germination Polymorphism in Rumex Crispers: The Effects of Different Storage Conditions on Germination Responses of Seeds Collected from Individual Plants. Canadian Journal of Botany. 52:575-583, March 1974. Christensen, C., ed. 1974. Storage of Cereal Grains and Their Products. 2nd ed. American Association of Cereal Chemists, Inc. St. P3111, MN. Chapman, S. and Carter, L. 1976. Crop Production Principles and Practices. W. H. Greeman and Co., San Francisco, CA. Copeland, L.O. 1976. Principles of Seed Science and Technology. Burgess, Minneapolis, MN. Copeland, L.O. 1977. High Quality Seed. Extension Bulletin E-1161. Cooperative Extension Service, Michigan State University. East Lansing, MI. 52 53 Cromarty, A.S., Ellis, R.H. and Roberts, E.H. 1982. The Design of Seed Storage Facilities for Genetic Conservation. International Board for Plant Genetics Resources. Rome. Das, N.D., Babu, D.V.N. and Setty, P.T. 1975. Seed Treatment and Its Effect on Storage, Germination and Seedling Height. Pesticides. Jan. 1975. p. 47. Delorit, R.J., Greub, L.J. and Ahlgren, H.L. 1974. Crop Production, 4th ed. Prentice Hall. NJ. Douglas, J.E. 1980. Successful Seed Programs: A Planning and Management Guide. Westview Press. Boulder, CO. Erdmann, M., Rossman, E. and Robertson, L. 1981. Profitable Corn Production in Michigan. Cooperative Extension Service, Michigan State University. East Lansing, MI. Finney, E.E., ed. 1981. CRC Handbook of Transportation and Marketing in Agriculture, Vol. II. CRC Press Inc., Boca Raton, FL. Grabe, D.F. and Isely, D. 1969. Seed Storage in Mbisture Resistant Package. Seed World. 1969, 104(2):2-5. Hanlon, J. 1984. Handbook of Package Engineering, 2nd ed. McGraw Hill Book Co., New York. Harrington, J.F. 1960. Drying, Storing, Packaging to Maintain Germination Vigor, Part I. Seedsmens Digest. Jan. 1960, p. 16. Hellum, A.K. 1973. Seed Storage and Germination of Block Poplar. Canadian Journal of Plant Science. Jan. 1973, p. 227-228. Isely, D. and Bass, L.N. 1959. Seed and Packaging Material. Proceedings of the 14th Hybrid Corn Industry Research Conference. p. 101. Jain, N.K. and Saha, J.R. 1971. Effect of Storage Length on Seed Germination in Jute. Journal of Agronomy. July-August, 1971, p. 636- 637. Jugenheimer, R.W. 1976. Improvement of Seed production and Uses. Wiley-Interscience Publication. New York. Justice, O.L. and Bass, L.N. 1978. Principles and Practices of Seed Storage . Agriculture Handbook No. 506. U.S. Government Printing Office. Washington, DC. Mangelshorf, P. 1974. Corn, Its Origin, Evolution and Improvement. The Belknap Press of Harvard University Press. Cambridge, MA. 54 Neal, N.P. and Davis, J.R. 1956. Seed Viability of Corn Inbred Lines as Influenced by Age and Conditions of Storage. Argon Journa. 48:383. Singh, J.N. and Maurya, M.L. 1972. Effect of Storage Conditions on Germination of Soybean Seeds. Bulletin of Grain Technology. Sept. 1972. p0 158“167o Srivastava, K. and Sareen, K. 1972. Germination of Soybean Seeds as Affected by different Storage Conditions. Bulletin of Grain Technology. Sept. 1972, p. 190-196. Thompson, J.R. 1979. An Introduction to Seed Technology. John Wiley and Sons. New York. Whitney, T. 1980. New Package Gives Seeds a Longer Life. Canadian Packaging. March 1980. p. 25. Wilton, A.C. and Rogler, G.A. 1978. Longevity of Alfalfa Seed Storage and Germination. Crop Science. -Nov.-Dec. 1978, p. 1091-1093. Hill 032 11111111131111111111