Effect of Calcium Source, Rate, and Time of Application on Soil Calcium Level and Yield of Peanuts (Arachis hypogaea L.)l

Transcription

1 Effect f alcium Surce, Rate, and Time f Applicatin n Sil alcium Level and Yield f Peanuts (Arachis hypgaea L.)l J. A. Daughtry and F. R. x 2 ABSTRAar Studies were cnducted bth in the labratry and in the field t determine the relative availability f calcium frm several calcium sulfate materials, and their effect n the yield and grade f peanuts. The initial rate f a leaching in the labratry study was greatest fr Phsphgypsum, medium fr the regular finely-grund anhydrite landplaster and least fr the granular anhydrite landplaster. With cntinued leaching the a level extracted after applying the three surces became similar. Sme differences were nted in the rate f leaching that were assciated with sil prperties, primarily catin exchange capacity. n the field, the materials were applied early in the seasn and at flwering. N cnsistent difference existed amng the surces in sil test a r S4-S levels during the grwing perid. These levels were lwer, hwever, late in the seasn if the materials had been applied early rather than at flwering. Similar cnclusins were reached when evaluating the temprary ph drp caused by applying the a surces. Yield and grade f peanuts were affected by applying the a surces in ne field study. The psitive respnse was similar frm the three materials which, in this particular study, were applied nly at flwering. Large-seeded peanuts ften need supplemental calcium in the surface few inches f sil fr prper fruiting (Brady, 1947; Reed and Brady, 1948; lwell and Brady, 1945; Bledse and Harris, 195). Fr the past 25 years, the methd mst cmmnly used t supply this element was described in a review by Yrk and lwell (1951) as fllws: "The best methd f applying gypsum t peanuts appears t be that f dusting the material n the plant at the early flwering stage. This relatively sluble surce f calcium falls arund the plant in the zne f pd frmatin and is present at the time when the need fr calcium is the greatest. t is essential that the gypsum be well distributed thrughut the zne f fruit frmatin. Since there is little residual effect f nrmal applicatins f gypsum (3 t 6 punds per acre), it is necessary t make annual additins f this material." Many pertinent factrs cncerning the methd f supplying calcium are included in this descriptin. The surce f calcium specified is gypsum. Data frm ther investigatrs (Reed and ummings, 1948; lwell and Brady, 1945; Rbertsn, Lundy and Thmpsn, 1965; Hallck, 196) indilpaper N f the Jurnal Series f the Nrth arlina Agricultural Experiment Statin, Nrth arlina State niversity, Raleigh, N.. The use f trade names in this publicatin des nt imply endrsement by the Nrth arlina Agricultural Experiment Statin f the prducts named, nr criticism f similar nes nt mentined. 2Frmer Graduate Student and Assciate Prfessr, Sil Science Department, Nrth arlina State niversity, Raleigh, N cate that gypsum is superir t less sluble surces such as lime. t must be assumed that the particle size is very fine, as indicated by the term "dusting." N studies cncerning the effect f particle size f gypsum applied t peanuts have been reprted. t is unknwn if the finely divided surce was selected n the basis f material availability, lgic r bth. This particle size may have been selected since gypsum must be disslved and the calcium mved frm the surface int the fruiting zne by rainfall. The time f applicatin was set at early flwering which begins abut 4 days after seeding, depending n variety and climatic cnditins, and cntinues fr 7-9 days (Schenk, 1961). Apprximately 1 days after a flwer frms the gynphre, r peg, which elngates frm its base enters the sil. Brady (1947) fund that the critical perid in which additinal calcium was needed was days after each peg reached the sil. Frm this bservatin and data regarding the fruiting perid (Harris and Bledse, 1951) it may be assumed that supplemental calcium is needed in the fruiting zne frm 7 t 135 days after planting. Since this perid encmpasses much f the last half f the grwing seasn, it wuld be lgical t expect that an applicatin during early flwering wuld be mre likely t insure adequate calcium when needed than an earlier applicatin, as at planting. Reed and Brady (1948) fund this tended t be true when they cmpared gypsum applied at seedling emergence and at early blm. Hwever, in three studies where a respnse t gypsum had been btained the later applicatin was significantly better in nly ne. One reasn why an early applicatin f gypsum might be less efficient is that calcium frm this surce is subject t leaching. Yrk and lwell (1951) stated there is little residual effect f 3 t 6 punds f gypsum per acre. x (1961) shwed n difference at harvest time in sil test calcium levels between such rates. Therefre, when dealing with a relatively sluble material, time f applicatin may be very imprtant. Fr the past 25 years, the calcium surce used in the Nrth arlina-virginia area was a pwdered calcium sulfate anhydrite cntaining ver 9~~ as4. As a bagged material it was spread in a band ver the rw with small equipment. Hwever, alternative materials are nw available that lend themselves t bulk spreading. Texasgulf, ncrprated, has a byprduct, called Phsphgypsum, frm their phsphate prcessing plant near Aurra, Nrth arlina. nited States Gypsum mpany has begun prducing granular landplaster at their plant in Nrflk, Virginia. T gain infrmatin n materials and their applicatin, studies were cnducted t determine (a) the rate calcium leaches frm each material under a set labratry cnditin and (b) the effect f 68

2 69 PEANT SENE time f applicatin and surce f material n sil test a and S4-S levels and n yield and grade f peanuts. Materials and Methds Three cmmercial materials used t supply calcium were investigated in all studies. The first was the regular "landplaster" that has been used in this area fr many years. t is a dry, pwdered calcium sulfate anhydrite cntaiuing 91 % aso,. The secnd was a mesh granular material with the same cmpsitin as the first. Bth f these were supplied by nited States Gypsum mpany. The third material was "Phsphgypsum'. t has als been called wet landplaster and wetplaster. t is a byprduct frm the phsphate prcessing plant near Aurra, Nrth arlina, which is perated by Texasgulf, ncrprated. The sample f Phsphgypsum used cntained 3 % H 2 and 51 % aso, calculated n a wet basis. t is variable-sized aggregate. Table 1. Sil test data cncerning the sils used in the labratry and field studies.t Sil Nrflk sl Lakeland s Rains fsl ph LABORATORY STDES The rate f disslutin and leaching f the calcium surces was studied by adding the surces t sil in leaching tubes, applying water, aud analyzing the leachate fr calcium. A fiber glass plug, then filter pulp, and finally a filter paper were first inserted in a 3.1 em diameter tube. On this, 65 g f sil were placed and cvered with anther filter paper. This gave a sil depth f 6.5 em (2.6 inches). Three sils were used in the labratry. Sme f their prperties are giveu in Table 1. The Nrflk (Typic Paleudult; fine-lamy, siliceus, thermic) and Rains (Typic Ochraquult; fine-lamy, siliceus, thermic) had similar quantities f extractable a, Mg, and K, while the Lakeland (Typic Quartzipsamment; siliceus, thermic cated) had cnsiderably less. The Nrflk and Lakeland had ph values f 5.8 and 5.7, respectively, but the Rains was mre acid with a ph f 5.. a s4-s Mg K (Kg/ha t 2 em) - - Sils used in labratry studies Sils used in field studies V.W. {glee) Nrflk sl Gldsbr fs Nrflk sl?: P O.M. ('7.) / Analyses cnducted by the Agrnmic Divisin, Nrth aehna Department f Agriculture, Raleigh. Results are calculated n a weight basis.?:.. Lcated at the Peanut Belt Research Statin, Lewistn, and referred t as Nrflk. After the three sils were placed in the tubes, water was added until it just began t drain ut the bttm. Each day thereafter, 1 ml (.52 inches) f water was added and the leachate cllected fr the' analysis. This quantity was selected as it wuld replace mst f the water present in the sil. The tubes were cvered t reduce evapratin. A preliminary study was cnducted with a labratry grade precipitated gypsum (aso, 2H 2, 79 % aso,). At the time the furth 1 ml increment f water was t be applied the gypsum was added by either f tw meth- ds. n ne case, 57 mg gypsum were spread under the surface filter paper and then the next 1 ml HO added. The ther methd was t make a suspensin f that quantity f gypsum in 1 ml HO and add it t the tube. The a cntent f the leachate was checked fr 17 successive increments f water. n these and all subsequent analyses, a was determined by atmic absrptin in a.5 % La slutin. n the final labratry study the three cmmercial calcium materials were applied t the surface f the ss as just described. The rates f the materials were 64 mg f the regular and granular landplaster and 113 mg f Phsphgypsum per tube. An identical prcedure was fllwed with these except that a ttal f 33 increments f water were added. n bth labratry studies each treatment was run in duplicate. FELD STDES Field studies were cnducted in 1973 utilizing tw applicatin dates, tw rates, and three surces f calcium materials. The tw times f applicatin were early, as near t planting as pssible, and nrmal, r at the beginning f flwering. Rates were a check, r zer rate, and an amunt t give 76 kg actual aso, per ha (68 b/ acre). The latter was bradcast ver the entire plt. Each plt was 15 m (5ft) lng and tw 9'-cm rws wide. Surces were the three cmmercial materials indicated previusly. A randmized cmplete blck design with six replicatins was used. Tw check plts were included in each replicatin, making a ttal f eight treatments per replicatin. One experiment was initiated n the W. B. Gilliam, Jr. farm near Harrellsville, Hertfrd unty, Nrth arlina, n a Nrflk sandy lam. Flrigiant peanuts were planted April 23 and the calcium materials applied May 22 and July 3. Rainfall was recrded during the seasn. Sil samples were cllected each three weeks after the initial applicatin until harvest. Each sample was cmpsed f 2 cres per plt taken t a depth f 1 em (4 inches). Sil analyses were made by the Agrnmic Divisin, Nrth arlina Department f Agriculture. The crp was dug September 1 and after curing, the yield and grade frm each plt determined. A similar study was initiated n a Gldsbr fine sandy lam (Aquic Paleudult; fine-lamy, siliceus, thermic) at the Peanut Belt Research Statin near Lewistn in Bertie unty. Peanuts were planted n May 3 and the early treatment applied May 4. This experiment was discntinued in midseasn because the entire study received an unscheduled applicatin f landplaster at early flwering. Anther study was then initiated n a Nrflk sandy lam in Field A2 n the Statin. The surces were applied nly nce, July 3, n Flrigiant peanuts that had been planted in early May. The same prcedures as utlined previusly were fllwed and the crp dug September 12. The 3 sites indicated abve will be identified hereafter as Nrflk, Gldsbr, and Nrflk, respectively. S11 test data frm the check plts are presented in Table 1. Results and Discussin LABORATORY STDES Applying the material in suspensin beginning with the 4th increment f water caused much mre rapid leaching f calcium than applying it dry t the sil surface (Figure 1). Maximum calcium cncentratin frm the suspended material was 25 ppm, whereas that frm the dry surface applied was 9 ppm. When added in suspensin the next 9 increments f H 2 (N. 4-12) remved essentially all the c a lei u m that was readily leached. f applied dry, hwever, the initial rate f leaching was cnsiderably slwer fr the first few increments than when applied in suspensin.

3 PEANT SENE 7 The striking difference in leaching rate due t methd f applicatin indicates that if finely divided gypsum is applied in suspensin, particles must be carried dwn int the sil. f spread in this manner, mre water wuld be available t disslve each particle. t wuld be expected that if gypsum were spread dry and then incrprated, as by disking, the rate f leaching wuld be similar t that when applied in suspensin. n cntrast, nt incrprating gypsum will prlng the time that it will supplement the sil a level. 8 4 Nrflk 24 E.. ~16 u <1> +-' -5 8 <1> -.J Suspensin D Dry Number f 1 ml HzO increment Ftg, 1. Effect f 2 methds f applying gypsum n the leachate a cncentratin after applying increments f water. Gypsum applied at arrw just prir t 4th increment. Values are averages frm duplicate analyses frm 3 sils. Minr differences assciated with sil type were nted in the amunt and rate f a leaching. Mre a leached thrugh the Lakeland than the Nrflk r Rains sils. Of the 57 mg gypsum (13,26 ug a) applied in suspensin 87% f the calcium was recvered frm the Lakeland sil between abut the 4th and the 12th extractins. During this same perid 67 and 6% were recvered frm the Nrflk and Rains sils, respectively. When applied dry, the percentages recvered between the 4th and 17th extractins fr the abve three sils were 62, 41, and 3%. This difference due t sil type wuld be expected frm the lwer exchange capacity f the Lakeland. Similar amunts f a were extracted frm the Nrflk and Rains sils, but the rate f leaching thrugh the Rains was slightly slwer. Whereas maximum a cncentratin in the leachate ccurred with the Nrflk at increment number 6, it ccurred with the Rains at increment number 7. n view f the abve results, it was cncluded that in future studies, any material shuld nt be applied in suspensin but shuld be spread n the sil surface. This was dne in the secnd labratry study and three cmmercial materials were evaluated n the three sils. The results f the secnd labratry study indicated that the initial rate f a leaching frm the materials was in the rder: Phsphgypsum > regular landplaster > granular landplaster (Figure 2). The rates became mre nearly similar as additinal water was added, thugh, and were essentially the same after increment number 14. t was expected that since the initial rate f leaching was least frm the granular landplaster it wuld eventually have a higher rate than th~ ther materials. This did nt ccur, hwever. n the early stages f this study, mre a leached thrugh the Rains and Lakeland sils than thrugh the Nrflk. These results with the Rains differ frm thse in the preliminary experiment. Althugh surce f material differs between the studies there seems n lgical explanatin fr this discrepancy. At the end f this study much less a was being leached frm the Rains than frm the Nrflk and La~eland.sils when the m~terials were applied. t,s pssible that th~ effective exchange capacity Wth a salt present S greater fr the Rains than fr the ther sils. f s, a may be retained lnger n exchange sites in the Rains. When the first increment f water was leached thrugh these sils, marked differences were bserved in the a cncentratin f the extracted slutin. The rder frm the sils was: Rains> Nrflk > Lakeland. This reflects a difference in the amunt and type f exchange capacity. FELD STDES Three experiments were cnducted in the field. Average sil test a and S4-S levels t a depth f 2 em frm the check plts during the seasn are given in Table 1. n the Nrflk and Nrflk studies bth a and S4-S varied smewhat especially in the first samples taken. There did nt seem t be any assciatin with rainfall pat-

4 71 tern r any ther factr that might explain this. There was a cnsiderable range in a levels amng sils, but the S4-S levels were all quite lw. The increase in sil test a and S4-8 ver that f the check plts resulting frm applicatin f the 3 cmmercial materials is shwn in Figure 3. There was n cnsistent difference amng the materials in increasing the sil test a r n 3 f the 4 cases the increase due t granular landplaster tended t be less than that frm the ther tw surces. This tendency decreased with time. 2 n Phsphgypsum 8 Granular n \ PEANT SENE, \ 'i. \~"",~ \ \ \.~ Regular 4> 1 1.c... E u OL :A--_-=-L _---L _.c f)... (jg f).~ 4> 1.c ọ s Nrflk O~ O : Nrflk,-_6 \ \ \, \ \.. \~~~ --~==~ Gldsbr Nrflk Q 7 7 ~ 9 :z Z ~ i 12 3' ' ' Fig. 3. hange in sil test a and levels during the seasn in relatin t that in the check plts when the 3 materials were applied. Since ittle difference existed amng surces in increasing sil test a and 84-8 the results were averaged. The data are presented in Figure 4 with time after applicatin. N data are reprted fr the sampling immediately after applicatin because the results were t variable. Althugh there is sme scatter in these pints due t lcatin differences, the general trend is fr bth a and 8 1-S t decrease with increasing time after applicatin. Frm 3 t 6 weeks after applicatin a decreased frm an average f 9 t 6, while 84-S decreased frm 17 t 4 kg/ha t a depth f 1 em. Even at the 3-week sampling values were much lwer than the actual amunt applied, which was abut 225 kg a and 18 kg 84-8/ha. Thus, in 3 weeks time a apparently had decreased t 4'% f that applied, while S4-8 had decreased t 9% f that applied. Sme f this culd have been lst in surface runff, but it is likely that much f it had been leached belw the surface 1 cm (4 inches) f sil. Anther means f evaluatin f the amunt f salt in a sil is by the decrease in ph. When salt is added it causes the ph t decrease. As the salt is remved by leaching the ph is increased. The sil ph values f the check plts during the sea- c Q) >,...,. E u ~ f) +J 2 ~ a V>... c rn ~... (1) 1 > a 5 22 ", ~, "c -~.:: ~ /'" "''' 6 12 ~...L...-_-'--_---.&-_--L,,"-- ~ 3 Weeks Nr-flk, early Nrflk, late 6. Gldsbr Nrflk 6.6 /- 6.4 Q. 6.2 tj) 6. \~/ after applicatin Fig. 4. hange in sil test a and S4-8 in relatin t that in the checks at the 3 latins with increasing time after applicatin. Values are averaged acrss the 3 surces Fig. 5. S ph f -1 em samples frm the Nrflk check plts during the seasn. sn n the Nrflk sil are shwn in Figure 5. During the first 3 weeks, between sample and 1, the ph decreased frm abut 6.2 t 5.9 The nly explanatin pssible fr this seems t be that surface evapratin caused salts t accumulate in that layer f sil. During the next 12 weeks the ph increased t almst 6.6, and remained there the next3 weeks. This increase was likely due t leaching f salts frm the -1 em hrizn.

5 PEANT SENE 72 The change in sil ph after applying the 3 cmmercial materials early and at flwering is given in Figure 6. n that applied May 2,2, Phsphgypsum decreased the sil ph mre than the ther surces in the early samplings, while the granular landplaster had the greatest effect in the later samplings. The latter data may indicate that granular landplaster may prvide mre a in slutin late in the seasn. Q. ell c: Q) Ol c: s: -4 6 Phsphgypsum Granular Regular O>~<;~.: "", 1/-/,) ~ c,.,, ,,1' -:" Fig. 6. hange in sil ph at the Nrflk site during the seasn after applicatin f 3 materials early in the seasn and at flwering., /1 " ~D When the materials were applied at flwering their effect in decreasing the sil ph appeared greater than when applied May 22 (Figure 6). Als, the effect remained greater fr 3 samplings r 9 weeks. This wuld suggest less leaching during the latter part f the seasn. On the Gldsbr site the ph was lwer (5.1 average) and shwed little change with either sample number, a rate, r surce f material. On the Nrflk site, hwever, the ph f the check plts increased frm 5.6 t 6. during 4 samplings. All surces initially decreased the ph in a similar manner. During the last 3 samplings the ph increased frm 5.2 t 5.7. Thus, at the last sampling the ph was.3 units lwer if the a materials had been applied. Peanut yields were nt affected by treatment at the Nrflk site. lwell and Brady (1945) estimated that if the sil cntained ver 67 kg alha by sil test a respnse t supplemental a was nt likely t ccur. The sil at the Nrflk site tested 96 kg alha t a depth f 2 em, s these results cncur with their estimate. 9 4 Yields were als determined frm the crp grwn at the Nrflk lcatin. This sil cntained 62 kg alha. Applicatin f the 3 materials increased the yield frm 47 t 55 kg/acre). N difference was nted amng' the 3 cmmercial materials, which were all applied at flwering in this case. Other differences nted in the crp between the check and the plus a treatments at the Nrflk lcatin were: heck Literature ited Landplaster SMK (%) ELK (%) Value ($/acre) Leaf a (%) Leaf S (%) All f the differences in these measurements were statistically significant (P =.1) except that fr leaf a which was just a trend tward being increased when landplaster was applied. Thus, the crp grade and value were increased substantially by each f the cmmercial materials applied. Leaf S was als increased by their use. At the Nrflk site leaf a and S were nt affected by treatment and averaged 1.65 and.18%, respectively. N plant samples were cllected in August frm the Gldsbr site as that study had been terminated by that time. Bledse, R. W. and H.. Harris The influence f mineral deficiency n vegetative grwth, flwer and fruit prductin, and mineral cmpsitin f the peanut plant. Plant Physil. 25: Brady, N The effect f perid f calcium supply and mbtltty f calcium in the plant n peanut fruit filling. Sil Sci. s, Amer. Prc. 12: lwell, W. E. and N.. Brady The effect f calcium n yield and quality f large-seeded type peanuts. Jur. Amer. Sc. f Agrn. 37: x, F. R The effect f plant ppulatin, varius fertilizers, and sil misture n the grade and yield f peanuts. Ph.D. Thesis. Nrth arlina State llege. niv. Micrfilms. Ann Arbr, Mich. Hallck, D. L alcium surces fr peanuts. Va. J. Science : 196 (Abstr.) Harris, H.. and R. W. Bledse Physilgy and mineral nutritin, hap. 4. The Peanut-The npredictable Legume. The Natinal Fertilizer Assciatin, Washingtn, D.. Reed, F. J. and N.. Brady Time and methd f supplying calcium as factrs affecting prductin f peanuts. Jur. Amer. Sc. Agrn. 4: Reed, F. J. and R. W. ummings se f sluble surces f calcium in plant grwth. Sil Sci. 65: Rbertsn, W. K., H. W. Lundy and L. G. Thmpsn Peanut respnses t calcium surces and micrnutrients. Sil rp Sci. Sc. Fla. Prc. 25: Schenk, R Develpment f the peanut fruit. Gergia Agric. Exp. Sta. Bull pp. Yrk, E. T., Jr., and W. E. lwell Sil prperties, fertilizatin and maintenance f Bil fertility, hap. 5. The Peanut-The npredictable Legume. The Natinal Fertilizer Assciatin, Washingtn. D..