THE EFFECTS OF WATER‘SOLUBLE MOWRUS CGNTENT AND GRANULE SIZE OF MéXED FERTELEZERS ON PHOSPHORUS AVAILABELKFY TO PiANTS Thesis for the Dogma cf M. S. WCWGAN STATE CON-EC?! Loweé! 2’3. Gwen: 1955' 1HESlS This is to certify that the thesis entitled The Effects of Water Soluble Phosphorus Content and Granule Size of Mixed Fertilizers on Phosphorus Availability to Plants presented by Lowell Owens has been accepted towards fulfillment of the requirements for Mdegree in Soil Science WLW Major professor Date W 0-169 THE! '59‘ . ‘\.__. THESIS TFE EFFECTS OF WATER-S )LUBLE PEIJSPFQRUS COT-FTENT AND GRANWLE SIZE 1? FIXED FERTILIZETS 3N PH JRPH JRUS INA ILAB I L ITY T J PLANTS By Lowell D. Owens N AN ABSTRPCT Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of mans-R as SCIENCE 19-55 Approved 0?. L. . 661% {‘45.ng Lowell Owens ABSTRACT 'The Effects of Water-soluble Phosphorus Content and Granule Size of Mixed Fertilizers on Phosphorus Availability to Plants Greenhouse and field experiments were undertaken to investigate the effects of water-soluble phosphorus content and granule size of mixed fertil- izers on the availability of phosphorus to plants. Wheat plants grown in the greenhouse showed no significant differ- ences in dry weight yields resulting from varying the water-soluble phosphorus content of mixed fertilizers having similar N-P205 -K20 ratios. Plant absorp- tion of phosphorus from granular fertilizers was directly proportional to the water-soluble phosphorus content of the fertilizer. The percent of plant phos- phorus derived from pulverant fertilizers was not markedly influenced by the water-soluble phosphorus content. There was a definite relationship between total phosphorus uptake by 3 week old plants and the water ~solub1e phosphorus content of the fertilizer applied, but the relationship was not observed in plants in a later stage of growth. Percent plant absorption of fertilizer phos- phorus decreased as soil pH was increased from 5.5 to 7.5. The phosphorus content of field grown sugar beet plants one month old was directly proportional to the water-soluble phosphorus content of the fertil- izer used. During later stages of growth, phosphorus absorption by the leaves lyr; (34" r? (‘4 Q_)\.I t 5" 1-; )4. Lowell Owens and petioles of beets from plots treated with fertilizers widely varying in their“ water-soluble phosphorus contents were not significantly different. Phosphorus uptake by sugar beet plants was not affected by variations in the mesh size of the materials tested. There were no significant differences in sugar beet yields resulting from fertilizer treatments. THE EFFECTS OF WATER-SOLUBLE PHOSPHORUS CONTENT AND GRANULE SIZE OF MIXED F ERTILIZERS ON PHOSPHORUS AVAILABILITY TO PLANTS By Lowell D. Owens A THESIS Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENC E Department of Soil Science 1955 ACKNOWLEDGMENT The author wishes to express his sincere appreciation to Dr. K. Lawton for advice and encouragement gven during the investigation and for his aid and council in the preparation of the manuscript. He also wishes to thank Dr. L. S. Robertson for his assistance with the field experiment and Drs. R. L. Cook and R. M. Swanson for their helpful suggestions and criticisms . TABLE OF CONTENTS PAGE INTRODUCTION................... 1 REVIEW OF LITERATURE . . . . . . . . . . . . . . 2 Effect of Phosphate Form on Plant Phosphorus Uptake . . . 2 Effect of Fertilizer Granule Size on Plant Phosphorus Uptake . . . . . . . . . . . . . . . . . . . . 4 Effect of Soil Reaction on Fertilizer Phosphorus Uptake . . 6 PROCEDURE . . . . . . . . . . . . . . . . . . . . 8 Greenhouse Experiment . . . . . . . . . . . . . . 8 Field Experiment . . . . . . . . . . . . . . . . 9 EXPERIMENTAL RESULTS AND DISCUSSION . . . . . . . l 1 Greenhouse Experiment . . . . . . . . . . . . . . l 1 Field Experiment. . . . . . . . . . . . . . . . . 3 8 SUMMARY . . . . . . . . . . . . . . . . . . . . . 4 2 LITERATURE CITED . . . . . . . . . . . . . . . . 4 5 MENDIX o o o o o o o o o o o o o o o o o o o o o 4 8 LIST OF TABLES TABLE I. IV. The Relative Uptake of Fertilizer Phosphorus by Wheat Plants from Mixed Fertilizers Varying in Water-Soluble Phosphorus Content and Mesh Size (Soil pH 5.5). . . . . . . . The Relative Uptake of Fertilizer Phosphorus by Wheat Plants from Mixed Fertilizers Varying in Water -Soluble Phosphorus Content and Mesh Size (Soil pH 6.5). . . . . . . . . The Relative Uptake of Fertilizer Phosphorus by Wheat Plants from Mixed Fertilizers varying in Water-Soluble Phosphorus Content and Mesh Size (Soil pH 7.5). . . . . . . . . The Effect of Rate of Application of Mixed Fertilizers on the Uptake of Total and Fertilizer Phosphorus by Wheat Plants Grown on a Hillsdale Sandy Loam Soil Limed to Three pH Levels.................... The Effect of Rate of Application of Mixed Fertilizers on the Dry Weight of Wheat Plants Grown on a Hillsdale Sandy Loam Soil Limed to Three pH Levels . . . . . . . . The Effect of Water-Soluble PhOSphorus Content and Particle Size of a Mixed Fertilizer on the Dry Weight of Wheat Plants Grown on a Hillsdale Sandy Loam Soil Limed to ThreepHLevels................ PAGE 12 13 14 25 38 39 LIST OF TABLES TABLE PAGE VII. The Effect of Water -Soluble Phosphorus Content and Particle Size of Fertilizer on the Phosphorus Content of Sugar Beet Plants and Yield of Beets. . . . . . . . . . . . . 40 FIGURE 1. LIST OF FIGURES PAGE The Relative Uptake of Fertilizer Phosphorus by Three Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and Mesh Size (soil pH 5.5). . . . . . . . . . . 15 The Relative Uptake of Fertilizer Phosphorus by Three Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and Mesh Size (soil pH 6.5). . . . . . . . . . . 16 The Relative Uptake of Fertilizer Phosphorus by Three Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and Mesh Size (soil pH 7.5). . . . . . . . . . . 17 The Relative Uptake of Fertilizer Phosphorus by Six Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and Mesh Size (soil pH 5.5). . . . . . . . . . . 18 The Relative Uptake of Fertilizer Phosphorus by Six Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and MeshSize (soilpH 6.5). . . . . . . . . . . l9 LIST OF FIGURES FIGURE PAGE 6. The Relative Uptake of Fertilizer Phosphorus by Six Week Old Wheat Plants from Mixed Fertilizers Varying in Water—soluble Phosphorus Content and MeshSize (soilpH 7.5). . . . . . . . . . . 20 7. The Relative Uptake of Fertilizer Phosphorus by Eight Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and MeshSize(soilpH5.5). . . . . . . . . . . 21 8. The Relative Uptake of Fertilizer Phosphorus by Eight Week Old Wheat Plants from Mixed Fertilizers Varying in Water-soluble Phosphorus Content and MeshSize (soilpH6.5). . . . . . . . . . . 22 9. The Relative Uptake of Fertilizer Phosphorus by Eight Week Old Wheat Plants from Mixed Fertilizers . Varying in Water-soluble Phosphorus Content and MeshSize (soilpH7.5). . . . . . . . . . . 23 10. Effect of Soil pH on the Relative Uptake of Phosphorus by Three Week Old Wheat Plants from Fertilizers of Varying Water-soluble Phosphorus Contents (meshsize4to6). . . . . . . . . . . . . 29 LIST OF FIGURES FIGURE PAGE 11. Effect of Soil pH on the Relative Uptake of Phosphorus by Three Week Old Wheat Plants from Fertilizers of Varying Water-soluble Phosphorus Contents (meshsizel4t020).. .. .. . .. . . . . 3O 12. Effect of Soil pH on the Relative Uptake of Phosphorus by Three Week Old Wheat Plants from Fertilizers of Varying Water-soluble Phosphorus Contents (meshsize-60).............. 31 13. Effect of Soil pH on the Relative Uptake of Phosphorus by Six Week Old Wheat Plants from Fertilizers of Varying Water—soluble Phosphorus Contents (meshsize4to6) .. 32 14. Effect of Soil pH on the Relative Uptake of Pho’sphorus by Six Week Old Wheat Plants from Fertilizers of Varying Water-soluble Phosphorus Contents (meshsizel4t020). . . . . . . . . . . . . 33 15. Effect of Soil pH on the Relative Uptake of Phosphorus by Six Week Old Wheat Plants from Fertilizers of Varying Water-soluble Phosphorus Contents (mESh Size ‘60) g o o o o o o o o o o 0. 0 0 34 IN TR ODUC TION The availability of phosphorus from fertilizers is influenced by certain factors that are inherent in the fertilizer, the plant and the soil. Recent inves- tigations have indicated that if only the fertilizer is considered, the water—sol- uble phosphorus content, the size of the fertilizer particles and the nature of the admixed salts influence the phosphorus absorption and dry matter yield. However, investigations of the interactive effect of solubility and particle size of phosphate fertilizers on the availability of phosphorus to plants has been largely confined to materials insoluble in water. Due to current processing trends in the fertilizer industry, considerable proportion of the phosphorus in many mixed fertilizers is or will be dicalcium phosphate, a relatively water-insoluble compound. Also, at present, increasing amounts of fertilizers are being produced in granular forms. Recent investigations have indicated that there is some correlation between fertilizer granule size and the availability of fertilizer phosphorus to plants. This investigation was undertaken to study the interaction of particle size and water—soluble phosphorus content of mixed fertilizers on the availability of fertilizer phosphorus to plants grown in the greenhouse and in the field. REVIEW CF LITERATURE Effect of Phosphate Form on Plant Phosphorus Uptake In 1949 Dion et a1. (4) found by means of a greenhouse and field ex- periment that there was a significantly greater utilization of fertilizer phos- phorus by wheat plants from mono -ammonium phosphate than from monocal- cium phosphate and tricalcium phosphate fertilizers. Their experiments were conducted on a neutral soil free of excess carbonates or alkali. Somewhat similar results were obtained from experiments performed on Texas soils by Speer et a1. (22) which disclosed that bean plants utilized a greater amount of phosphorus applied in the form of monoammonium phos- phate than in the form of dicalcium or tricalcium phosphate. Martin et al.(9) observed that the degree of ammonification of super- phosphate had no effect on the availability of phosphorus to lettuce plants grown on an acid soil. However, when applied to a calcareous soil the growth response of the lettuce was related to the amount of water-soluble phosphorus in the fertilizer. Rogers (18) compared the relative effects of ammoniated superphos- phate and concentrated superphosphate on several crops grown both in the greenhouse and in the field. He concluded that there is no evidence that a high water—solubility (over 10%) is required for small grains, corn and cotton grown on acid soils in the southeastern states. However, limited tests in Iowa 3 and Nebraska suggest that nitraphosphates of low water—solubility may on alka- . line soils be less effective than the more soluble superphosphate. In 1953 Mitchell et a1. (12) observed that 25 percent of the phosphorus in barley, wheat and cat plants grown on a slightly responsive soil was derived from ammonium phosphate fertilizers, but at the same time there was a corre- sponding decrease in the uptake of soil phosphorus. On highly responsive soils the utilization of fertilizer phosphorus was as high as 33 percent, while the up- take of soil phosphorus was about the same as that on an untreated soil. Experimentation by Hall et a1. (5) has shown that the phosphorus uptake by com plants was greater from superphosphate and metacalcium phosphate than from dicalcium phosphate fertilizers. However, the uptake from superphosphate and calcium metaphosphate, which have widely different water-soluble phosphorus contents, was virtually the same. Using the absorption of fertilizer phosphorus by cotton plants as a measure of phosphorus availability, they observed that on both high and low phosphorus soils, phosphorus Uptake from dicalcium phosphate was less than that from four other phosphate fertilizers, alpha tricalcium phosphate, superphosphate, ammoniated superphosphate and calcium metaphosphate. Similar observations were made by Stanford and Nelson (23) who found that phosphorus absorption by oats was greater from superphosphate than from dicalcium phosphate. Greenhouse studies conducted by Moschler (13) have shown that ammoni- ation of superphosphate lowers its availability to wheat in early stages of growth. 4 Field data suggest that this reduction in availability may be masked by un- favorable growing conditions such as the lack of sufficient moisture. Experiments conducted on irrigated calcareous soils by Olsen et a1. (15, 16) have shown that the total uptake of phosphate from the soil and applied phosphates was about the same from treatments involving fertilizers of widely varying water-soluble phosphorus contents. Calcium metaphosphate furnished less phosphorus to the plants in the early stages of growth than did superphos- phate, but the plants obtained about equal amounts of phosphorus from these fertilizers in later stages of growth. Dicalcium phosphate was not as effective as superphosphate in supplying phosphorus to wheat, barley and sugar beets. Effect of Fertilizer Granule Size on Plant Phosphorus Uptake The effect of granule size of radioactive superphosphate and dicalcium phosphate fertilizers on crop yield, total plant phosphorus uptake and percent fertilizer phosphorus uptake was studied by Starostka et al. (24). Using these results as a criterion for evaluation these workers observed that 14 to 20 mesh size granules of superphosphate were most effective while 28 to 35 siZe gran- ules were the best for dicalcium phosphate fertilizers. Rogers (18), using crop response as a criterion of fertilizer effective- ness, indicated that granules of phosphatic fertilizer coarser than 12 mesh were less effective than finer materials. On the other hand there was some evidence that particles finer than 40 mesh were also inferior. 5 Mitchell et a1 (11) observed that the utilization of fertilizer phosphorus from a granular state was significantly greater than from a pulverized state. Similar results were reported by Sayre (19) who observed that granul- ated fertilizers gave superior yields in all field tests on tomatoes where the fertilizer was applied broadcast. The same occurred with three of four fertil- izers applied in bands. Using cotton yields as a criterion for evaluating the efficiency of var- ious sized superphosphate granules, Mehring (10) stated that for the average circumstances encountered in their experiments the 80 to 150 mesh fertil- izers were the most efficient. Lawton and Vomicil (7) showed that rapid dissolution of phosphorus from the fertilizer granule occurred shortly after it was placed in the soil. Be- tween 50 and 80 percent dissolution of the phosphorus occurred within the first 24 hours in moist soils. However, high concentrations of water-soluble phosphorus around the fertilizer pellet decreased the rate of dissolution. The phosphorus in larger granules was found to migrate the greatest distance. On the other hand Killinger (6) observed from an experiment with cot- ton that fertilizer particle size did not significantly affect the stand or yield. Van der Bauw as quoted by Sherman and Hardesty (20), has stated that granulation reduces the assimilability of Cal-904. However, this is not true in the case of water-soluble phosphates (superphOSphates). Experimentation by Torstensson and Eriksson (25) and also by Franck (21) has disclosed that in pot tests with cats and barley, granulated superphos- pie? [8 fart-are ules . ready 4‘ suitable mmsn arid. T SLEEP)? W superpho: more star acid in th Stu Dhoms fen Phorus on t Celtratlon 1' FIOpemes u however, an compoqus, GIGEI 6 phate was superior to the powdered product. The use of granulated material favored a good root development which partially encircled the fertilizer gran- ules. Franck, as quoted by Sherman and Hardesty (21), has concluded after nearly a decade of phosphate experimentations that "Superphosphate is more suitable in the granular form---The large particles are able to saturate soil zones in such a way as to enable the roots easily to take in the phosphoric acid. The phosphoric acid which has been taken in can be replaced from the supply which has not yet completely reacted with the soil, that is, from the superphosphate particles themselves. The granulated superphosphate is a more stable phosphate and provides a more constant supply of phosphoric acid in the soil." Effect of Soil Reaction on Fertilizer Phosphorus Uptake Studies by Cole et a1. (2) indicate that the addition of soluble phos- phorus fertilizers to calcareous soils results in monolayer sorption of phos- phorus on the surface of calcium carbonate particles. If the phosphorus con- centration is amply high, dicalcium phosphate or a compound with similar properties will form a precipitate. The initial products of these reactions, however, are more soluble in regard to phosphorus than more stable phosphorus compounds, such as hydroxyapatite and fluorapatite, found in calcareous soils. Greenhouse studies on the effect of lime on the availability of applied 7 phosphorus were conducted by Robertson et a1. (17). It was found that lim- ing soils of a high sesquioxide content and low phosphorus level resulted in an increase in applied phosphorus availability up to a pH of 6. 5. Liming the soil beyond pH 6. 5 caused a leveling off or drop in the utilization of fertilizer derived phosphorus. This was due to the formation of an insoluble calcium- phosphorus complex. In 1953 Neller (14) found that liming an acid soil to raise the pH to 6.76 had no effect on the percent uptake of fertilizer phosphorus, however, it decreased the total phosphorus content of cats and millet grown in the green- house. Field studies, though, revealed that liming had no effect on the plant absorption of either the applied or soil phosphorus. Speer et al. (22) observed that the absorption of phosphorus from mono- ammonium phosphate fertilizer was greater on acid soils than on alkaline cal- careous soils. Phosphate fixation studies by Lewis et a1. (8) indicate that on cal- careous soils, a reduction in plant availability of applied phosphorus took place in the first 24 hours, after which it leveled off and tended to maintain a constant level. PROC EDURE ' Greenhouse Experiment The soil used in this experiment was a Hillsdale sandy loam taken from the SW 1/4 of Sec. 20, T 3N, R 1W, Meridian township, Ingham county, Michigan. The pH of the soil was 5. l and the quantity of available phosphorus extractable in 0. 13N HCl was low. Three soil pH levels, 5.5, 6.5, and 7.5 were obtained by liming With precipitated CaCO3 , followed by three weeks moist incubation prior to fertilizer application. Six 12-12-12 fertilizers1 hav- ing variable percentages of their phosphorus water-soluble were used. These percentages were 2 to 3, 8 to 10, 18 to 20, 28 to 30, 40 to 45 and 85 to 90. The fertilizers were synthesized from CaHPO4, NH4H2PO4, NH 4N03 and KCl in slurry mixtures. Phosphorus water-solubility was varied by changing the proportion of ammonium to dicalcium phosphate with adjustments in am- monium nitrate to keep the N to P205 ratio the same. All of the fertilizers were labelled with P32 and prepared in the mesh sizes 4 to 6, 14 to 20 and minus 60 per inch. Except in a fertilizer application rate study all fertilizers were uni- formly mixed with the soil at the rate of 500 pounds per acre. For the appli- cation rate study 14 to 20 mesh sized fertilizers having 28 to 30 percent of their phosphorus water-soluble were applied at the rates of O, 30, 120 and 1The 12-12-12 fertilizers labelled with P32 were prepared by W. L. Hill and associates, Fertilizer and Agricultural Lime Division, Agr. Re- search Service, Beltsville, Md. 180 pounds of P205 per acre. Three replicates of each treatment were em- ployed. The soils were placed in four gallon glazed pots, and Henry variety of spring wheat was planted on March 9th at the rate of 30 seeds per pot. Op- timum moisture conditions were maintained by bringing the soil up to an esti- mated value of moisture equivalent at periodic intervals. Two thinning sam- ples and a final harvest were taken on April 2nd, April 21st, and May 8th, re- spectively. The plant samples were dried at 65°C., weighed, ground and a one gram portion pressed into a pellet at 14, 000 pounds per square inch. After obtaining measurements of their specific activity the pellets were wet ashed with nitric, sulfuric and perchloric acids. Residue of the ash was taken up with 0.2N HCl and phosphorus determined as molybdenum blue by the Dick- man and Bray method (3). Field Experiment Four non-radioactive fertilizersl, including 7-14-14, 6-12-12, 10-20- 20 and 11-22-22 analyses with water-soluble phosphorus contents of 0, 25, 50 and 100 percent, respectively, were used in this experiment. Two particle sizes, 6 to 14 and finer than 35 mesh, of each formulation were tested. This experiment was conducted on Kawkawlin loam soil in Bay County, Michigan. The variation in soil pH from six replications was 6. 8 to 7.5. Phos- phorus and potassium extractable in 0. 13N HCl averaged 41 and 115 pounds lFertilizers having a 1-2-2 ratio were supplied by the Soil and Fer- tilizer Research Branch, Agr. Relations Division, T.V.A. , Knoxville, Tennessee. 3.? EMS”. MM 0 J i u v, a i . . r (I H t _ e . o I u '\ . i A , I a . i \ . ~ A. — ' . o a _ l‘ t o _ e 9. 10 per acre,respectively. A total of 140 pounds of P205 was applied broadcast, ‘ one half before plowing on April 22nd and the remainder topdressed after plow- ing on May 18th. The experimental design was a randomized block with six replications, each 14 by 31 feet. Beet seed was planted on May 20th in 28- inch rows. Plant samples for total phosphorus analyses were taken from each plot 4 and 8 weeks after planting. On October 8th the beets were harvested. EXPERIMENTAL RESULTS AND DISCUSSION Greenhouse Experiment A greenhouse experiment was designed to measure the plant availability of phosphorus from mixed fertilizers. Variables under investigation included water-soluble phosphorus content and mesh size of fertilizers and soil reaction. The data given in Tables I, II, and 111 (see Appendix for data by repli- cates) and Figures 1 throngh 9 show that the plant absorption of phosphorus from the 4 to 6 and 14 to 20 mesh 12-12-12 fertilizers was markedly increased as the water -soluble phosphorus content was increased. Wheat plants obtained less than 12 and 17 percent of their phosphorus, respectively, from 4 to 6 and 14 to 20 mesh granules of fertilizers containing less than 3 percent of their phosphorus water -soluble. This condition was true for all pH levels. In contrast, the per- cent of plant phosphorus derived from 4 to 6 mesh particles having over 85 per- cent of their phosphorus water-soluble rose at the final harvest to over 75 at pH 5.5 and 6.5, and over 50 at pH 7.5. Large granules with a low content of water- soluble phosphorus did not afford sufficient surface for extensive dissolution and root contact. 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Anna own 3 Flr % I. om om oa o _ \\ \ _ .XJw \I||.l|l|2 \ ./ ”K O\\ L q\\\\\\\\< OH ON on on on 102111110; max; ponzoq moquom 1mg JO queued 6 1|. .An.m ma afiomv ouwm gum: dad pmwpnoo mduosmmonm oapfiaomnnmumz aw mmwmuw> muouaauphoh den“: 80pm upadam ammzx oHo goo: moans up usuonmuogm gouafifipnom Mo oxapga opflpmaom age .N madman noudafipuoh a“ cansaomuaopmz «Shonmmonm mo «noonom om ow on co on 0: mm om 0H T 7, fl m . _ _ _ _ @ guoa omsaa nos ml: 0H 0N T on . o: Y on on zozttxqzo; mos; poataoq cnzoquaqg guatg :0 quoozad l7 .An.m mm afloav oufim Mao: and announce agonmmonm 3933:8033 a.“ wafnhdb unouuganoh 2332 39C 3an 9625 v.8 Moos 0939 hp agonmuonm nougaonoh mo SHED 0531“” SE. .n earn youuagnoh a.“ oapfiaounaouwz 353935 no unmouom om om om ow on o: on . om » OH 0 .l L. w _ w d . .1 q o \4 \\ // \\. 1,9... in - 1|! l..\ /.\q Mnfloa 8.! \. \. l cu .. a /d I; OM acne omnda d . x o: Amos ml: 1% on d‘ 18 ;, on Jazz-[121.105 no.1; ponxoq smoquoqd 1mg :0 among 00 l .Am. n mm adouv exam nae: dam unopqoo unnoamuonm oflgsao¢.nopu: fl mqfihum> «youuaflunoh douflx scum upuaam aaon: ado xaoz Mam by qpuonmuogm noNfiadpuoa mo oxaugu opflgaaom one .: onsmfia “333.3% a.“ oandaonnaopdb 3539935 no unconom om om on cm on o: om om b[oa o —| J _ u _ 4 — fl d 1 Q/, // . // /I l // /o\\\o.\c\ I] .flnas../ L 4\OOI+~H \\Qo .1 \4 J ._ 0 OH ON on on on vow om zest-[11.10; cox; paused moquoqg 4mm :0 41190195 9 l .Am.m mm Haouv ouum :3: 93 33:00 £539an oaapaomnnopms 3.. @538; uuouaaapnoh won“: 395. 33m 23:: v.8 Moo: Nam up «Eggnog .333»qu no oMmpgb ozumaom 2a. .m 03mg Ramadan—nah ‘3 03381333 naoamuonm no «593% om mm! on cm on on on om ca 0 . _ A q _ . _ _ . Q nuoa ml: OH on 303111139; no.1; panama moquoqg 4mm 30 41:03:03 .Am.m mm afiouv oufim duo: dud unoaaoo ushonmuogm oHAaHoalaopdz a“ mqamnd> uuouaaapuoh can“: aéum .anaam paoga ado Moo: «an an canonmuogm nauflaflaaon no oxapga o}dpuaom egg .m onswam nouuaapnoh ad oaanaounfioaa: ushonmaogm Ho pqooaom nv om cm on om on c: on 0N ca 0 9. WM . q» u m . \4 ~ _ .‘ 'l I I \./z .\ . . \ // \\x / \\‘ II -l....|...\ /\ .4 name 00 I . q f . 4\ . \ OH ON on .0“ on 1021111301 max; poatzoq InJoqdboqa guard 30 queoxad 1 2 .Am.m mm Agony ouam new: and unmadoo ndhonmuonm magsaounnopdz da muuhnd> muonaaaahoh don“: Bony .paaam amen: vac x0»: onwam an usuonguonm youdaflpuou no mxauga opflauflom age .5 gunman honaaapuoh a“ capaaownaopdz udhonmnonm Mo unmouom om om o5 om on as on om o” 7 _ A _ fl _ d _ _ // I I o\o .III.I.II:.\\\1\\\\ I/I/ 4 \A \\\o #005 8|- 4 o Ill. 03 ONIJH d .a 3 OH Von on om om om zozttthog mos; pOAtzoq cnzoquoqg aunt; JO annexe; 22 And mm 33 Anna 0N1: naoa ml: . Ago: find 23.230 agonmaonm capsaounuopmr ad wading» =32”:qu «on any“ 393m .595 30 Moo: anmum .3 Eamuonm nonaaaphoh Mo 33pm: 033.33“ one .0 25m: «unaduhoh a.“ oapfiaonluopdx mafimuonm mo 9:093...” om ow 2. 8 on 3 on cm 2 .1 _ _ a . _ _ J _ 4 o I l l I .l Rnfloa OW- 0/0 o\\\\|o 0.." ON on on on om om JOBtIIQJO‘ mos; mung mandsma 111915 JO queued 3; 2 .Am.u mm agony ouam Ago: dud aqopnoo «shonmaonm oandaomunopax a“ wafihnw> nuonaaaauoh can“: Boga .aqaam uaogu ado goo: ”swam ha asuonmaonm noudaaauoh no oxapga o>duaaom oga .m ousmdm noudaauuoh da oanfiaonlfioudr onuonmnoam no «noouom om om on cm on c: on ow ea o W _ m _ q _ _ d _ q. . \ \. \\ // . \\. \\\ 4 .\\\\ IIII |1||| .\\ \ “A“.a 8|- q I: «a Amos ml: anoa omn:a o." .om on c: .on on zozttxazol‘uoxg pOLtIOa Inzoquoqg auutd JO guessed 24 plants can be made from data presented in Tables I, II, and III. It was ob- served tbat as the percentage of water-soluble phosphorus in the 4 to 6 and 14 to 20 mesh sized fertilizers increased from 2 to 85 the variation in uptake of fertilizer phosphorus by wheat plants was more than 0. 65 mg/ gm plant material at the 8 weeks old and more than 1. 50 mg/ gm at the 6 weeks old stage. These relatively wide differences indicate that a direct relationship existed between fertilizer phosphorus uptake and the water-soluble phosphorus content of the fertilizer. In contrast, the variations in uptake of total phosphorus by wheat plants receiving these same treatments were less than 0.90 mg/gm plant material at both the 6 and 8 weeks sampling time, and were generally consid- erably less when compared to corresponding variations in fertilizer phosphorus uptake. Also, no definite relationship could be established between total plant phosphorus uptake and the water-soluble phosphorus content of fertilizer. These data seem to indicate that at later stages of growth the water- soluble fraction of fertilizer phosphorus is the more readily available source of phosphorus to wheat plants. After depletion of this source, phosphorus from the soil is then absorbed by the plant until a relatively near optimum level is reached. This reasoning is further substantiated by data presented in Table IV (see appendix for data by replicates) where soil pH and fertilizer application rates were the only variables considered. As phosphorus applica- tion was increased from 30 to 180 pounds of P205 per acre the uptake of fertil- i_El'u. nou- ~-;:- uv._ I i “ii I .r UNI.» 11.4.3". nNr JW 25 .33 wnfimfiwm some Hm woumotmn you and 3.53 “Ame: .mnoumofinou 085 no owmugd: 6338-833 msuoammoam Ho 360qu on 8 mm was oflm :88 cm 8 3... cm m4 mud om m. mm; on ¢.N 34 o3. mw N.4 mm .o aw 0.N me; mm m .N «w .o omd ma 0.N omd 3 m.m omd 3 w.~ and on w 4 «EN «KN o mg mg 3 N.4 «to; me Wm on; ma. o.m on?“ om: mw 1N mod om «IN .34 cm o4... mo; ONH mm m4 mic vm 0.N wvd ma 0.N and cm a .H m. .N a .N O we we mo w; mmJ mo w.N RJ om m.m we; 03 mo w; 54 on «in me; am 0.N wmofi ONH om N.N mm .0 cm w.N mud mm «SN 86 on o4 o.m 04 t o m.m ma Eton—9h . Enough H3338 mm Ema EMRE mm 329 EMEE R puma EwEE .95“ m 3:3 .95“ A Show .98“ m .flou 89a m ”:33 89a m th m Ema Bod m th m 3de Bod A onus Hum 35 38, “use “use 38. SE sea 38. ”.qu mo mm goo? m goo? 0 flow? m mcazom 3% 32am /{ l|I|‘|\IIIIIIII| .Eo>2 In 025 3 8:5 mom Ewofi bosom @3333 a no :3on ...:muefln “won? l3 ......maonamona “3:93 28 33 Ho ofias ma 8 amswnufi 858 Mo condemned Ho 83 «o Soho 2:. .3 £ng 26 izer phosphorus by 6 and 8 week old plants increased over two-fold in all instances, while the total phosphorus absorption showed no definite varia- tion trend as related to the application rate. These interactions do not hold, however, for the 3 week old wheat plants, in which the uptake of both total and fertilizer phosphorus from 4 to 6 and 14 to 20 mesh fertilizer treatments was directly proportional to the water-soluble phosphorus content of the fertilizer. However, as the amount of phosphorus water-soluble in the fertilizer was increased, the increase in absorption of fertilizer phosphorus was considerably greater than that of total phosphorus. Therefore, the plant absorption of soil phosphorus de- creased as the portion of phosphorus water-soluble in the fertilizer was in- creased. This relationship suggests that limited plant root extension and dissolution of phosphorus out of the granules resulted in total phosphorus ab- sorption that was somewhat below the optimum level of the plant. These limitations wereovercome by increasing root extension and phosphorus dis - solution during later stages of growth. Plant uptake data from 6 and 8 week old plants show that wheat plants were eventually able to absorb a near opti- mum amount of phosphorus regardless of the fertilizer water-soluble phos- phorus content. The relationships between plant uptake of total phosphorus from minus 60 mesh sized fertilizers and the water-soluble phosphorus content of the fertilizer were somewhat similar to those obtained using granular 27 fertilizers. The variations in uptake of total phosphorus at the 3 week ‘ sampling, however, were much smaller than corresponding variations from granular fertilizers. Less than 15 percent difference in percentage of plant phosphorus from pulverant fertilizers was recorded for the entire range of water-solubility, regardless of soil pH or stage of plant growth. The rela- tively uniform plant absorption of fertilizer phosphorus from pulverant materials of low and high water-soluble phosphorus content can be explained on the basis of fixation and dissolution of phosphorus from its compounds. Although essentially insoluble in water, dicalcium phosphate (2 to 3% H20- soluble) in the finely divided state presented considerable surface area for dissolution and root contact, resulting in a fairly high availability. Phos- phorus in pulverized mono ~ammonium phosphate (85 to 90% HZO-soluble) moved quickly out of very fine particles into the soil, where a considerable portion became fixed in the soil into forms not readily available to wheat plants. This reaction left but slightly greater amounts of readily available phosphorus in the soil than did dicalcium phosphate. These two different reactions resulted in soil-fertilizer systems having rather similar amounts of phosphorus available to plants, regardless of the water-soluble phos- phorus content of the fertilizer applied. Plant absorption of phosphorus from 14 to 20 mesh materials of vary- ing water-soluble phosphorus content was intermediate to that from 4 to 6 and minus 60 mesh particles at each pH level. However, the values for plant uptake of phosphorus from these medium sized particles more closely 28 resembled those obtained from the large particles than those obtained from the use of material finer than 60 mesh. From the data in Tables I, II, III, and IV it can be observed that the relative phosphorus contents of the wheat plants at the 8 weeks sampling time were generally somewhat lower for all treatments than those from 3 and 6 week old plants. Liming an acid soil is believed to have resulted in the formation of relatively insoluble calcium phosphates or reduced the proportion of H2P04" ions in the soil solution. As shown by data presented in Tables I, 11, III, and IV and Figures 9 through 18. percent plant absorption of fertilizer phos- phorus was highest from soils at pH 5.5, intermediate at pH 6.5 and lowest at pH 7.5. Tests for available soil phosphorus and field observation indicated a need of phosphate fertilization for optimum crop growth. However, the data presented in Tables V and VI show that the dry weight yields of wheat plants at the full heading stage were not significantly affected by the vari- ables under investigation. Somewhat similar results were reported by Martin et al. (9) who observed that the degree of ammoniation of super- phosphate did not affect the yield of lettuce grown on four acid Califor’nian soils deficient in phosphate. However, when phosphate was applied to a calcareous soil the growth response of the lettuce was related to the amount of water-soluble phosphorus in the fertilizer. Starostka et a1. (24) also re- ...... - J. a n Fails? I, In! it. v .1. filial. t 39:86.1} Fig .3 o» d on: Ado—av announce ushonmuonm oaAfiaoannopaz mnuahm> no unouaaaanoh scum candam anon: dao Moo: conga an udhonmnonm mo oanga obuudaom on» no mg neon mo noommm .oa unawah noudaapuom a“ oagfiaounnmuns canonmncnm no aaoouom 9 2 ow om ow on c: on .ON W u on . _ m.n mm d + .oa VON .8 on on untrue; nor; peatroq IMO‘quOQJ 31mm queued “IE Eiiu again“? .Aom on +2 on? £35 .3038 agonmuonm oapfiaounuoudz waumua> no uhouflnguoh Bonn manna..." pang) Bo x33 3.29 B Buchanan." .«o 339.: «Saddam 2: no we do» no 38E .2 cash nonnaauoh a.“ oanfiaoulnopdb Eggnog no 3.93m .0- om om on 8 on 3 on om 2 o 3 9 q d _ q — _ — q o on .rozunza; nor; WAIIOQ 31110ququ aunt; queue; 3.1 announce agonmuonm oaflfioulfiopd: ’33:: .i‘..' INJ. Ital ‘ .1u .11] r w J >\‘ o. ; IuKV. “W . A8! an: #35 Magnum; no 3333.35” scam «and; v.02; So no»: 3.5. B «flogged Mo 833p 3:38 on... 3 mm :3 no poets .3 93m; Houuaavuoh a.“ oapfiaoolkopdk acnmmonm Ho unconom cm on on 8 on 3 on om 2 o q _ 4 _ a q _ . . c \Q o\ mé mm \\\ ,// \x\ i S q d. N . O n W wurr O \ I. ON \\ / \o 9m mm L. on on on Jeannie; nor; nausea moquoqg 3mg arrears; .. _ ~ J . . I. ~P if .. lvdliv... ~..I. 210.1.» hill‘l‘gh .3 on .a on? Anon—v 3838 35333." £938.33: 3:8.» mo 23:32.." 28m 33.8 use. So ~83 as .3 .Eofiuofl no 3.3%: 3:33 8: no mm do» no 88a .9 93m: nouuaavuoh nu cagsaoonaoads adhonmuonm no «nooaom 2 8 cm on 8 on 3 cm cm 3 o 3 _ _ _ _ _ _ _ _ _ o \o\\\\u\\ \\\\ mgmm \\ . \\ \\ €\ \.\ \.\\\.\ , .\ \3 ma ...8 lld . Q‘\O\ “ tom .mmm low untrue; I01; poawoq woquoqd 41mm gnome; 3 3 .Aom on :H onuu nwoav announce udhonnuoam oagsaounnoams wnahum> no muouaaflouoh 269m «padam anon: So x8: «3 .3 353328 no 83qu 333mm on» no mm :8 .3 38.8 4: 93mg nouaaupuoh a“ canvaounaoud: ndkonmuagm mo «noonom om 8. 2. 8 on 3 on cm 3 o 4 u q J|A _ 1 . fi d .m ma om rozrtrgro; nor; poaraoq Inzoquoqd aunt; queers; “ma. ..1. .9 “Ii?! ‘lthlaltr: .rnilvivlgld a DISIII’ls— .Aoo|_0uam nuoav announce ufihonmwonm oagsaonlaoada wnamnd> mo nausaadanoh scum uaaoam soon: So ”to: n3 .3 ufiosaaofi mo $3.5 3333a 2: no me Gem .3 33.3. .3 9:63 honaaaunom dd capfiaomnampmz adhongmogm no onoouom 4 om 8 2. 8 on 3 on om S o 3. .1 a s _ _ _ . n . \IJ/ \\ \ I \ ...l. lull. I. III I ..l nlll..\ /o \l OH ON on on ow om om .roznuzq no.1; poured monium 3mg moored .3 on a 3.3 £35 .2338 unnonmuonm oHanouluoada waning». no unouaagnoh Ion..." Snag «333 So no... 33..» 3 aonmafim no 9.33 253cm 2: no mm flow. no Sofia .3 93mg 803320..” 5 0353.39.03: 3539.08.” Ho «quench om cm 2. 8 on 3 cm ow 2 o _ _ d d + _ W _ J J o - 5' . 3 o." ./\. l n 2 mm o . I 3 J on o . “.0 N9 d 1 8 n.“ ma 1 a . .1 8 Jeannie; no.1; ponxoq moquoqa 41mm 4119:)er 6‘ 3 .Aom on :H onam nuoav nadopnoo uduonmuogm candaounnoad: mdahuds no unouaaapnoh noun unadam anon: vac Mun: anwfifi hr nauonmiagm no cucumb o>Hp¢aom on» do manaom Ho aooufifi .ma casuah uouaaaonoh ad oanaaoajnoudj udhonmnogm no anoonom om om on 8 on 3 on om- o." o #1, ‘4‘ H _ d a A _ _ o \o L \\\\\\\\W\\\\\& 4K<\o . O\ 0 n4. mm .. a o 00 mm q “A E 1 0H ON on on on om om xeztttaze; I03; poataaq sn;oquoqg zuatg zuOOJOJ .Aow|_0u«u Auoav .aaouaoo unuonmmogm oapfiaonnnoumz wauhum> mo unouuHApuoh noun ouqdam pdons So no; Swan 3 afimgfi no 33% 2.33am 2: 3 mm :8 no 88mm .3 93mg acnaaaphoh a“ oagaaouIQOpmx ashonmuogm Ho anachom 7 om .8 2. 8 on 3 on on 2 o 3 _ fi _ _ _ A _ A _ n4. mm \. \\o / \ \o‘_\ \ I/O\ I a» u.|II....|II |.|I|| I. I. . m.m mm ca ON on on on xeztttho; mos; poataoq InloqdhOQd guuta zuooxoa )I Lrufldwubiki... In“ 38 Table V. The effect of rate of application of mixed fertilizers" on the dry weight of wheat plants" grown on a Hillsdale sandy ' loam limed to three pH levels. Dry weight yield of wheat plants*** Pounds P 0 2 5 H 5.5 H 6.5 H 7.5 per acre p p p pounds gins/pot gms/pot gms/pot 0 13.0 13.3 13.4 30 13.4 13.4 13.7 120 12.9 12.9 13.3 180 13.3 13.9 13.6 L. S. D. at 5% level N.S. N.S. N.S. ‘14 to 20 mesh size and 28 to 30 percent of phosphorus water-soluble. "Six plants per pot harvested 8 weeks after seeding. "*Average of three replications. ported no yield response from varying the mesh sizes of either superphos- phate and dicalcium phosphate fertilizers applied to a sandy clay loam soil. Field Experiment A field experiment was conducted to evaluate the effects of water- soluble phosphorus content and mesh size of four 1-2-2 ratio fertilizers on the phosphorus content of sugar beet plants and yield of beets. Values given in Table VII show that with one exception the two mesh size materials tested, 6 to 14 and minus 35, had no significant effect on total phosphorus uptake by sugar beet plants. 39' .mdoflwonmou 830 no ommuo><3 .3530 152303 Sod moaoflom 9:... 8282 00:.qu hdcooou 0N muaomoaou wcflafimm goo? ”Ems ”mace... mafia manna 0N 3:08am“ wcflafiwm 3695 50m... .m.z 85 22,2 0% 00.0124 0.2 >20 0 00.0 0.. mm 002 5.2 0N.0 w 0N.0 v E 8 0 002 grams: 0.0 00.0 0 NN.0 w 00 om 0N-0Nu02. 5.0 00.0 0 0N.0 w 3 8 0 00 00-00-02 N02 2.10 0 2 .0 0 mm mm 2.20 0.2 0N.0 0 010 v 3 8 0 mm 2.20 0.2 0N.0 0 2 .0 v mm 0 3-3;. 5.02 0N.0 w 2 .0 w E 8 0 0 3-3.4. 803908 280.50 9603 :05 “mm ”:50qu Soon .....osmmfl :83 1.95930 0338- $33 00 .56 Ho SHE 800 oNMm msconmmozm mambmcm 3m; Eon—coo m woflafimm smog Ho :ofluom uoflfitom .muoon 00 Born 98 Emma moon “swam «o “50:00 maonamona 05 no 8223.60 00 05m 20330 new 0:808 msuonmmonm “0338-333 Ho ”.0020 9F .9» 0309 c 41 It was observed however, that as the percentage of water-soluble phosphorus in the fertilizer was increased from 0 to 100 the plant tissue phosphorus content increased from O. 15 to 0.25 percent at the time of the 4 weeks sampling date. This trend indicates that fertilizers with low water-soluble phosphorus contents do not provide enough phosphorus to the plant for optimum growth, when available soil phosphorus is low. This conclusion was further substantiated by the fact that there was a greater prevalence of black root disease in plants on plots receiving the 7-14-14 and 6-12-12 fertilizers. Vigorous young seedlings are not highly suscep- tible to this disease. However, continued dissolution and plant root exten- sion resulted in similar phosphorus absorption from plots treated with ferti- lizers of widely varying water-soluble phosphorus contents. Yield data in- dicate that there were no significant differences resulting from fertilizer treatments. The relatively low yields obtained from all of the plots were due to an unfavorable planting season. Approximately five inches of rain fell in the last week of May, and a poor stand of beets resulted. 42 SUMMARY Greenhouse and field experiments were undertaken to determine the effect of water-soluble phosphorus content and granule size of mixed fertilizers on the availability of phosphorus to plants. In the greenhouse experiment wheat plants were grown on Hills- dale sandy loam soil limed to three pH levels. Field observations and laboratory tests indicated the soil to be low in available phosphorus. Six 12-12-12 fertilizers having from 2-3 to 85-90 percent of their phosphorus water-soluble were used. All the phosphorus in these materials was citrate-soluble. Each fertilizer was labelled with P32 and prepared in mesh sizes of 4 to 6, 14 to 20, and minus 60 per inch. Fertilizers were applied at the rate of 500 pounds per acre and the soil placed in four- gallon jars. The following results were obtained: 1. Plant absorption of phosphorus from granular fertilizers was directly proportional to the water-soluble phosphorus content of the fertilizer, regardless of growth stage. 2. Soil-fertilizer systems resulting from pulverant fertilizer application had similar amounts of phosphorus available to plants regard- less of the water-soluble phosphorus content of the fertilizer. 43 3. Absorption of total phosphorus by 3 week old wheat plants was directly proportional to the water-soluble phosphorus content of all mesh sized fertilizers tested. 4. At later stages of growth no relationship existed between the uptake of total phosphorus by the plant and the water -soluble phos- phorus content of the fertilizer. 5. Percent plant absorption of fertilizer phosphorus was highest from soils at pH 5.5, intermediate at pH 6.5 and lowest at pH 7.5. 6. Phosphorus content of wheat plants was generally less at the full heading stage than at earlier stages of growth. 7. Dry weight yields of wheat plants at the full heading stage were not significantly affected by the variables under investigation. In a field experiment sugar beet plants were grown on Kawkawlin loam soil of pH varying from 6. 8 to 7.5. The soil tested medium for available phosphorus. Four 1-2-2 ratio fertilizers having from 0 to 100 percent of their phosphorus water-soluble were used. All the phosphorus in these materials was citrate-soluble. Mesh sizes 6 to 14 and minus 35 per inch of each formulation were tested. A total of 140 pounds of P205 was applied broadcast, one-half before plowing and the remainder after plowing. The results may be summarized as follows: EB..I¥§IE3 FHH 44 1. Plant absorption of total phosphorus at the 4 weeks sampling was directly proportional to the water-soluble phosphorus content of the fer- tilizer. Four week old sugar beet plants grown on plots treated with fertilizers low in water-soluble phosphorus showed phosphorus deficiency symptoms. 2. During later stages of growth sugar beet plants absorbed similar amounts of phosphorus from plots treated with fertilizers of widely varying water-soluble phosphorus contents. 3. The two mesh sized materials tested, 6 to 14 and minus 35, had no significant effect on phosphorus uptake by sugar beet plants. 4. Sugar beet yields failed to show any significant differences resulting between fertilizer treatments. LITERATURE CITED (1) Blaser, R. R. and McAuliffe, G., "Utilization of phosphorus from various fertilizer materials: I Orchard grass and Ladino clover in New York, " Soil Sci. 68: 145-150. 1949. (2) Cole, C. V., Olsen, S. R., and Scott, C. 0., "The nature of phosphorus sorption by calcium carbonate, " Soil Sci. Proc. 17: 352-356. 1953. (3) Dickman, S. R. and Bray, R. H., "Colorimetric determination of phosphate," Ind. and Eng. Chem., Anal. Ed. 12: 665-668. 1940. (4) Dion, H. G., Spinks, J. W. T., and Mitchell, J. , "Experiments with radioactive phosphorus on the uptake of phosphorus by wheat," Sci. Agr. 29: 167-172. 1949. (5) Hall, N. 8., Nelson, W. L., Krantz, B. A., Welch, C. D., and Dean, L. A., "Utilization of phosphorus from various fertil- izer materials: 11 Cotton and corn in North Carolina, " Soil Sci. 68: 151-156. 1949. (6) Killinger, C. B., "Fertilizer particle size experiment with cotton in 1937," S. Car. Proc. Natl. Joint Comm. Fertilizer Application, 13th Ann. Meeting, pp. 58-59. 1937. (7) Lawton, K., and Vomocil, F. A., "Dissolution and migration of phosphorus from granular superphosphate in some Michigan soils," Soil Sci. Proc. 18: 26-32. 1954. (8) Lewis, G. C., Baker, G. 0., and Snyder, R. S., "Phosphate fixation in calcareous soils," Soil Sci. 69: 55-62. 1950. (9) Martin, W. E. , Vlamis, J. and Quick, J., "Effect of ammoniation on availability of phosphorus in superphosphate as indicated by plant response, " Soil Sci. 75: 41-49. 1953. (10) Mehring, A. L., White, L. M., Ross, W. H., and Adams, J. R., " Effects of particle size on the properties and efficiency of fertilizers," U. S. Dept. Agr. Tech. Bul. No. 485, p. 27. 1935. l alrigfti'i 0:1 9 (ll) (12) 46 Mitchell, J. , Kristjanson, A. M. , Dion, H. G. , and Spinks, ‘ J. W. T. , "Availability of fertilizer and soil phosphorus to grain crops and the effect of placement and rate of application on phosphorus uptake," Sci. Agr. (Ottawa) 32(10): 511-525. 1952. , Dion, H. G., Kristjanson, A. M. and Spinks, J. W. T. , "Crop and variety response to applied phosphate and uptake of phosphorus from soil and fertilizer, " Agron. Jour. 45(1): 6-11. 1953. (13) Moschler, W. W. , "Effect of ammoniation of superphosphate on (14) (15) (16) (17) (18) (19) (20) its availability to wheat, " Proc. 5th Ann. Phosphorus Work Conference Southern Region, pp. 91-92. 1954. Neller, J. R. , "Effect of lime on availability of labeled phosphorus of phosphates in Rutledge fine sand and Marlboro and Carnegie fine sandy loams," Soil Sci. 75 (2): 103-108. 1953. Olsen, S. R. and Gardner, R.,"Utilization of phosphorus from various fertilizer materials: IV SUgar beets, wheat and barley in Colorado," Soil Sci. 68: 163-169. 1949. J Schmehl, W. R., Watanabe, F. 8., Scott, C.O., "Utilization of phosphorus by various crops as affected by source of material and placement, " Colo. Agr. Exp. Sta. Tech. Bul. 42. 1950. Robertson, W. K., Neller, J. R. and Bartlett, F. B., "Effect of lime on the availability of phosphorus in soils of high to low sesquioxide content, " Soil Sci. Proc. 18: 184-187. 1954. Rogers, H. T ., "Crop response to nitraphosphate fertilizer, " Agron. Jour. 43: 468-475. 1951. Sayre, C. B., "Granulated fertilizers," Proc. Natl. Joint Comm. Fertilizer Application, 12th Ann. Meeting, pp. 117-120. 1936. Sherman, M. S. and Hardesty, J. 0, "Review of experimental work on the agronomic effects of particle size of superphos- phate and of mixed fertilizers containing superphosphate or other water -soluble phosphates, " Plant-Food Memorandum Report No. 20, p. 25. 1950. ii ...-In!!! ...;an . . ,y _ fo‘w .ip. '\ I l. V . V\ r. v» n .\ . \ Q a . It '\ o a u n 0 pk . / (v I O o . Q o !\ O . o . v V. I e v C o t D 47 (21) , "Review of experimental work on the agronomic effects of particle size of superphosphate and of mixed fertilizers containing superphosphate or other water- soluble phosphates, " Plant-Food Memorandum Report No. 20, p. 29. 1950. (22) Speer, R. J., Allen, S. E., Maloney, M., and Roberts, A., "Phosphate fertilizers for the Texas Blacklands, " Soil Sci. 72: 459-464. 1951. (23) Stanford, G. and Nelson, L. B., "Utilization of phosphorus from various fertilizer materials: 111 Oats and alfalfa in Iowa," Soil Sci. 68: 157-161. 1949. (24) Starostka, R. W., Caro, J. H. and Hill, W. L., "Availability of phOSphorus in granulated fertilizers, " Soil Sci. Proc. 18: 67-71. 1954. (25) Torstensson, G. and Eriksson, S., "The fixation of phosphoric acid in Cytta soils," Lantbruks-Hogskol. Ann. 5: 377- 403. 1938. Chem. Abs. 32: 5140. 1938. .nl'- a. .n..rl.ln~ APPENDIX 49 Table 1. The relative uptake of total and fertilizer phosphorus by wheat plants from mixed fertilizers varying in water-soluble phosphorus content and mesh size (soil pH 5.5). Portion Mesh of P Plant P from fertilizer sampling date size H20-sol. 3weeks 6weeks 8weeks Total plant phosphorus Sampling date 3 weeks 6 weeks 8 weeks % 2t03 4to6 8to 10 18 to 20 28 to 30 40 to 45 85 to 90 14t020 2t03 8to 10 mg/ gm plant material 0.21 0.14 0. 14 0.48 0.48 0.48 0.64 0.60 0.55 mg/gm plant material 2.3 1.5 2.3 2.3 2.2 2.2 2.2 2.1 2.1 2.4 2.4 2.2 2.6 --- 1.9 3.0 2.4 1.8 2.7 2.3 1.6 3.2 2.1 1.2 3.2 2.6 2.1 3.2 2.5 1.5 3.3 2.4 1.8 3.2 2.3 2.1 3.2 3.0 1.7 4.1 2.5 1.1 4.2 2.6 1.1 4 4 2.5 1.6 4.4 2.7 1.5 4 l 2.9 1.4 1.6 2.4 1.8 2.2 2.7 2.4 2.1 --- 2.1 2.4 --- 2 0 2.2 2.4 2.1 2 2 2.1 2.0 50 Table 1 (cont. ). 0.81 0.72 18 to 20 006 221 134 o o o 222 0.82 0.99 0.99 0.91 8 8 28 to 30 0.69 0.77 0.86 1.25 1.33 1.42 1.46 1.89 1.89 40 to 45 2.1 2.9 2.5 2.8 O 7 5 o o 0 l l l 5 _ 9 O _ O 2 n l 3 5 2 o o o 3 3 3 7 2 6 8 l l o O o 0 1 1 7 - 8 8 _ 0 o _ o l — 2 6 7 1 8 O o o 2 2 l 0 9 0 t 5 8 2.4 2.6 0.96 0.71 0.62 0.62 0.79 0.62 0.46 0.54 0.37 iZto 3 minus 2.2 2.7 60 2.2 2.3 2.0 2.8 0.78 0.65 8to 10 1.8 0.82 1.05 0.82 0.96 0.68 0.64 0.67 18 to 20 0.64 810 o o o 122 200 o o o 222 0.62 0.75 0.67 0.62 5 4 28 to 30 090 o o o 212 340 222 462 o o o 222 0.67 7 8 0.75 8 7 0.63 6 5 40 to 45 1.8 51 Table 2. The relative uptake of total and fertilizer phosphorus by wheat. plants from mixed fertilizers varying in water-soluble phosphorus content and mesh size (soil pH 6.5). Portion Mesh of P size HZO-sol. Plant P from fertilizer Sampling date 3 weeks 6 weeks 8 weeks Total plant phosphorus Sampling date 3 weeks 6 weeks 8 weeks % 2t03 4to6 8to 10 18 to 20 28 to 30 40 to 45 85 to 90 14t020 2t03 8to 10 mg/ gm plant material 0. 10 0. 10 0. l4 0. 10 0. 10 0. 10 0.21 0. 14 mg/ gm plant material 2.7 2.3 2.0 2.5 2.3 1.6 2.4 1.9 2.0 2.5 2.3 1.5 2.6 2.3 2.1 2.4 ~-— 1.7 2.4 2.1 2.1 2.0 2.2 2.3 3.1 2.3 1.9 3.4 2.0 1.4 3.2 2.0 1.8 2.9 2.5 1.5 3.0 2.5 1.2 3.8 2.0 1.4 3.4 2.1 1.6 4.2 2.9 1.3 4.6 2.6 1.3 4.0 2.6 1.3 2.4 2.0 1.8 2.5 2.4 1.3 2.6 2.1 1.8 2.4 2.0 1.8 2.6 2.0 2.1 2.5 1.8 1.7 52 Table 2 (cont.). 172 coo 17 22 2.9 3.1 0.47 0.47 0.55 0.51 0. 68 0. 64 0. 51 0. 60 0. 60 18 to 20 0.56 0. 69 0. 60 28 to 30 43 12 3O 22 98 o o 22 0.95 0. 69 0. 60 0.99 1.08 0.99 0.99 1.08 1.03 40 to 45 2.0 2.1 2.9 3.0 3.7 0.71 1.04 1.08 1.91 1.79 1.71 1.83 1.87 1.83 85 to 90 2.9 3.6 2.2 3.8 220 0.. 222 535 o o o 222 633 o o o 222 0.58 0.50 0. 46 0.46 2 to 3 ---- 0.25 0.29 minus 60 0.78 0.70 0.31 8to 10 203 o o o 222 788 o o o 221 853 o o o 222 0.68 6 6 0.37 3 3 18 to 20 0.50 0.33 28 to 30 0.58 0. 54 0.38 40 to 45 0.44 0.57 0.47 85 to 90 53 Table 3. The relative uptake of total and fertilizer phosphorus by wheat plants from mixed fertilizers varying in water- -soluble phosphorus content and mesh size (soil pH 7. 5). Portion Plant P from fertilizer Total plant phosphorus MeSh of P Sampling date Sampling date size 1120-501. 3 weeks 6 weeks 8 weeks 3 weeks 6 weeks 8 weeks % mg/ gm plant material mg/ gm plant material 4 to 6 2 to 3 0.10 0.10 0.10 2.4 --- 1.1 0.10 0.10 0.10 2.4 2.0 1.8 0.10 0.10 0.10 2.5 2.1 1.3 8 to 10 ---- 0.52 0.26 2.9 2.4 1.5 0.39 0.61 0.26 2.6 2.4 1.0 0.30 0.56 0.22 2.6 1.9 1.0 18 to 20 0.77 0.77 0.38 2.9 1.9 0.9 1 06 0.81 0.34 3.2 2.4 1.5 0.94 0.64 0.34 3.0 2.3 1.4 28 to 30 0.87 0.69 0.39 3.0 2.5 1.5 0.78 0.87 0.35 3.1 2.3 1.9 0.95 0.95 0.35 --- 2.1 1.5 40 to 45 1.34 1.18 0.39 3.2 2.7 1.1 1.38 1.10 0.59 3.6 2.8 1.4 1.18 1.02 0.59 3.1 2.4 1.7 85 to 90 1.73 1.69 0.86 3.5 2.9 1.7 2.34 1.64 0.83 3.9 2.8 1.4 1.81 1.77 0.70 3.9 2.9 1.4 14 to 20 2 to 3 0.08 0.08 0.16 2.6 2.4 1.8 0.08 0.08 0.12 2.5 2.8 1.7 0 08 0.08 0 12 2.5 1.7 1.7 8 to 10 0.20 0.28 0.16 2.3 2.3 1.8 0 24 0.24 0.20 2.5 2.2 2.2 0.24 0.24 0.24 2.8 2.4 2.3 54 Table 3 (cont.) 2.1 2.3 0.60 0.26 0.55 18 to 20 2.2 0.69 0.43 0.43 28 to 30 1.08 0.56 0.731 40 to 45 0.92 0.87 1.71 1.33 1.66 1.37 1.33 1.33 85 to 90 3.3 1.7 1.9 2.9 0.47 0.25 0.25 0.29 0.21 0.25 0.21 0.12 0.21 21x>3 rninus 2.3 2.4 60 2.2 2.9 0.26 0.31 0.22 8to 10 023 222 482 o o o 222 929 000. 222 0.27 0.46 18 to 20 0.21 0.21 0.21 28 to 30 2.1 0.37 2.7 2.8 0.37 0.37 0.37 1.8 2.8 2.8 2.9 0.42 0.33 0.46 40 to 45 0.50 0.37 0.47 851D 90 '— It] .4... I 55 Table 4. The effect of rate of application of mixed fertilizers“ on the relative uptake of total and fertilizer phosphorus by wheat plants grown on a Hillsdale sandy loam soil limed to three pH levels. Pounds Plant P from fertilizer P205 Sampling date Total plant phosphorus Sampling date per acre 3 weeks 6 weeks 8 weeks 3 weeks 6 weeks 8 weeks pounds mg/ gm plant material mg/ gm plant material pH 5.5 0 1.8 2.8 2.0 1.5 3.3 1.5 1.6 3.1 2.0 30 0.60 0.73 0.48 2.5 2.9 2.1 0.60 0.78 0.48 2.4 --- 2.4 0.48 0.73 0.60 2.2 2. 2.1 120 1.25 1.77 1.25 2.6 2.7 1.8 1.34 1.77 1.08 2.7 --- 1.9 1.38 1.56 1.12 2.5 2.2 1.6 180 1.64 1.64 1.25 3.3 2.8 2.0 1.68 1.99 1.25 3.3 2.7 2.0 1.56 1.68 1.30 3.2 --- 1.5 pH 6.5 0 1.9 2.8 1.9 2.3 2.3 2.0 2.1 2.5 1.8 30 0.43 0.48 0.43 2.7 2.0 2.1 0.39 0.56 ---- 2.4 --- 1.9 0.39 0.43 0.39 2.7 --- 1.8 120 1.12 1.25 ---- 3.2 2.2 2.1 1.08 1.21 0.91 2.9 2.5 1.9 1.04 1.12 0.99 2.9 2.4 2.3 180 1.30 1.68 1.21 3.1 2.5 2.5 1.34 1.56 0.86 2.9 2.2 1.1 1.21 1.47 0.99 2.9 2.4 1.6 56 Table 4 (cont. ) pH 7.5 1.8 1.7 2.5 2.3 2.8 2.5 2.1 2.5 ...-1.. .4. . . killing-["453 6278 I... 2222 0777 I... 3222 0508 3337 00.0 0000 5998 3330 O... 0001 0062 3328 .00. 0000 0 0 3 2 l . .9 EH! 3165!: 2.1 l l 1 l 2.5 2.2 2.7 3.0 2.1 2.7 2.9 3.0 2.8 3.0 0.86 0.82 0.86 0.65 0.73 1.17 0.99 1.43 1.12 1.21 0.73 0.91 1.12 1.04 0.99 180 *14 to 20 mesh size and 28 to 30 percent of phosphorus water-soluble. . n.‘ w} *w r V" aulv cc 2 <5 saws—1:35:12? m May 26 '58 ...“A.,__.« .. _ I 7 -— a- \ MICHIGAN STATE UNIVERSITY LIBRARIES mum HI |||3|| 4 3 1293 031017 30