Growth and Development of Cotton As Affected by Toxaphene-DDT, Methyl Parathion, and Calcium Arsenate!

Growth and Development of Cotton as Affected by Toxaphene-DDT, Methyl Parathion, and Calcium Arsenate!

LAMAlI C. BROWN, G~1011GBW·. CATHB¥, and CflAIlL~';;;LINCOLN2

AnSTIlACT l?ormulations of the insecticides toxaphene-DDT, methyl para- boll production if tr'eatments were initiated when the oldest bolls thion, and calcium arsenate were utilized in two experiments con- were about 30 days old and continued at weekly intervals for 5 ducted in 1960 to investigate further the inflnence of insecticides weeks. Yield and boll production were not affected by trcatments on growth a nd development of cotton. with methyl parathion. Calcium arsenate reduced yield and boll Insecticide treatments had no significant effect on internode production when t.reatments were initiat.ed at the Hppearance of length, number of internodes, plant height, per cent of bolls shed, first. squares and cont.inued weekly for 12 weeks. Calciurll arsena t.e germination, per cent lint, and the boll components seed index, treatments of less dUlation had no significant effef·t on yield and Downloaded from https://academic.oup.com/jee/article/55/3/298/2207328 by guest on 30 September 2021 lint index, boll weight, Hnd seeds per bolL boll production. An increase in yield and boll production oecurred when tOXH- Number of leaves and dry weight of plants were signifieantly phene-DDT was applied to cotton at weekly intervals for 12 and increased by eertain treHtments of methyl parathion and signifi- 8 weeks beginning with the appearance of first sqnares and first cantly deereased by eel'lain t.reatment.s of caleium 'lI'senate; flowers, respectively; toxaphene-DDT had no effeet 011 yield and toxaphene-DDT had no effeet on lear number and dry weight.

An experiment conducted in 19.5!J showed an effect of growing season. Cotton was treated once with a 16-8 dust toxaphene-DDT and calcium arsenate on cotton in the mixture of Strobane® (tel'pene polychlorinates (65% absence of populations of damaging insects (Brown et a!. ch]orine))-DDT at the rate of ]8 pounds pel' acre. The 19(il). In the experiment, insecticide treatments were bollworm was controlled, and no damage was detected in initiated when cotton was at the cotyledonary stage of the experimental plots. plant growth and were terminated after 7, 12, and 16 Experiment .1 consisted of four replications of a split- weekly applications. One of the more significant effects plot design with main plots as fertilizer treatments (N or attributed to treatments of toxaphene-DDT was an in- no N) and sub-plots as insecticide treatments (toxaphene- crease in boll production in plots tl'eated for 12 and 16 DDT, methyl parathion, and an untreated check), Each weeks; bowever, any advantage was offset by a concurrent sub-plot consisted of three rows 50 feet long, Data were reduction in boll size and weight, and yield was not af- taken only from t.he center row. The N plots were side- fected. Trcatmcnts with calcium arsenate for 6 and 12 dressed with 50 pounds of elemental nitrogen pel' acrc, consecutive weeks had no effect on boll production, boll with ammonium nitrate as the carrier, 5 days before the size, boll weight, and yield. However, a significant reduc- initiation of insecticide treatments. The insecticide treat- tion in these components was attributed to 16 weekly ments were begun when cotton first began flowering and applications of calcium arsenate. Height was suppressed were terminated after 8 weekly applications at which time by both toxaphene-DDT and calcium arsenate. Two ex- the plants had "cut-out" and about 11% of the bolls were periments, therefore, were conducted to investigate fur- open. ther the effects of certain insecticides. on growth and Experirnent 2 consisted of four replications of a sp]it- development of cotton. plot design. Main plots were insecticide treatments l\fl';TJIODS.-Two field experiments were conducted at (toxaphcne-DDT, methyl parathion, calcium arsenate, the University of Arkansas Experiment Station, Fayette- and an untreated check). Sub-plots represented timing ville, Arkansas, in 1960. This location was chosen for the with respect to initial insecticide application, which sub- field experiments because naturally occuning populations sequently resulted in differences in total numbe/' of insecti- of insects harmful to cotton are relatively low in the cide applications; i.e., Series 1 was initiated at the ap- Fayetteville area. The insecticides consisted of a mixture pearance of the fil'st squares and insecticide treatments of toxaphene-DDT at a rate of 2 pounds of toxaphene to 1 were continued at weekly intervals for 12 weeks; the pound of DDT applied in 10 gallons of water pel' acre, insecticidc trcatments were begun in Series 2 when cotton calcium arsenate (high suspension) at acre rates of 10 began flowering and were continued at weekly intervals pounds in 10 gallons of water, and methyl parathion at for !) weeks; Scries 3 was initiated when the oldest bolls acre rates of 0.25 pound in 10 gallons of water. The insecti- were about 30 days old and insecticide treatments were cides were applied with a self-propellcd high-clearance continued at weekly intervals for 5 weeks. At the time the rig. The high-clearance rig also was moved through the insecticide t.reatments wcre terminated, thc plants had check plots so that any damage caused by ground machin- "cut-out" (final cessation of flowering and plant growth) ery would be essentially the same in all plots. App]ications and about 12% of the bolls were open. Each sub-plot con- were madc when wind velocity was nil and no drift prob. sisted of three rows 30 feet long. Data were taken only lems were encountered. The cotton variety Plains (Gos- from the center row. sypiurn hirsuturn I .•.) was utilized in both experiments and RESULTS.-Cotton in Experiment 1 showed no response plants were spaced at intervals of one plant per 12 inches I Published with the approval of the Director of the Arkansas Agricaltural of row; row width was 40 inches. The plots were checked Experiment Station. Aceepted lor publication October 9, ]901. for insects several times each week and the only problem 2 Plant physiologist and Research Agronomist~ Crops Uesearch Division. encountered during the growing season was a 3% infesta- Agric. Res. Serviec, United Stntt."s Department of Agriculture, and ]~nto- moJogist-, Agric. Experiment Stlltion) Unh'crsity of ArknnsnsJ l'~n~'ettc\'iIle, tion of bollworm (Heliothis zea (Boddie)) ear]y in the respecti vely. Q98 ./ 1lne. J96:2 BROWN ET AL.: GROWTH O~' COTTON AS AFFEC1'ED BY INSECTICLDES

Table I.-Effects of toxaphene-DDT and methyl para- Table 3.-Yield and number of bolls produced as affected thion on yield, boll production, per cent shed of bolls and by treatments of toxaphene-DDT, methyl parathion, and squares, number of leaves, and dry weight of plants, calcium arsentate, Experiment 2. Experiment 1. INSECTICIDE& TnlING No. o~·BOLl.~ DMY S~;m~~s PRODUC~~D ~O. OF No. Ol~ "'EIGHT IN8 E('TlCl 0 E YIELD BOLLS SHEn LEAVES i)~::R PLANT Tf{~;A'I'.u"]NT (LIJ.) PU.ODU('Erl (%) l'Io;n PI~ANT (G.) Toxaphenc-DDT: Series I 4.38 ]08 TOXH phcnc-D D'l' 7. ~.; 111 4.;.1 8~ ~H.8 l\fcthyl Plll'lllhion 5. S.; ns 46.7 811 38.4 Series 2 4 .•58 113 Cheek 6.1.J. 100 4fi ..5 81 ~l~l.H Series 3 3.77 99

L.S.D. @ 5% le,.el 1. O~ NS 3.0 iVIean 4.24 ]07

Mcthyl parathion Downloaded from https://academic.oup.com/jee/article/55/3/298/2207328 by guest on 30 September 2021 to fertilizer treatments (no significant differences between Series 1 3.21 ]00 main plots) and no significant fertilizer X insecticide inter- Series 2 3.42 ]()J Series 3 3.60 10() actions. Significant differences among yield, boll production, numbe,' of leaves, dry weight of plants, and earliness, .M.ean 3.41 100 however, were attributed to certain treatments of the insecticides. Both yield and boll production were signifi- Calcium arscna le Series 1 3.00 !)() cantly increased in plots treated with toxaphene-DDT; Series 2 3.47 98 methyl parathion showed no significant effect on yield or Series 3 3.(H 100 boll production (table 1). However, a significantly greater number of leaves and a significant increase in dry weight .Mean 8.3G !Ui occurred in plots treated with methyl parathion; toxa- Cheek phene-DDT did not affect the number of leaves or the dry Series 1 3.li8 100 weight of plants. As shown in table 2, the per cent of open Series 2 3.68 100 bolls on a given date was significantly less in cotton treated Scries 3 3.1i.5 100 with methyl parathion than in the check plots; earliness Mean 100 was not affected by treatments with toxaphene-DDT. There were no significant differences among treatments L.S.D. @ .5% for eomparing with respect to internode length, number of internodes, any two treatment means 0 ..52 8 height, per cent of bolls and squares shed, germination, pel' cent lint, and the boll components seed index, lint production in Series 1 of the calcium arsenate treatment index, boll weight, and seeds pel' boll. Except for data on (table 3). Treatments of methyl parathion showed no per cent of bolls and squares shcd, tabular data from both significant effect on yield and boll production. Experiments 1 and 2 that showed no significant differ- Neither the number of insecticide applications nor thc ences among treatments have been omitted from this number of applications X insecticide interaction showed paper. significance regarding the number of leaves 01' dry weight The analysis of data from Experiment 2 showed the of plants. However, the data showed significance with interaction between insecticides and time of initiation of respect to insecticide treatments. Treatments of methyl treatments (number of insecticide applications within a parathion resulted in a significant increase in number of series) to be significant with respect to yield and boll pro- leaves and dry weight, whereas calcium arsenate caused a duction. There was a significant increase in both yield and significant decrease in number of leaves and dry weight boll production in Series 1 and 2 of the toxaphene-DDT (table 4); toxaphene-DDT showed no effect on leaf num- treatments and a significant decrease in yield and boll ber and dry weight of plants. Earliness was not affected by treatment of toxaphene-DDT or calcium arsenate . Table 2.-Earliness as determined by the per cent of bolls .l\1aturity, however, was delayed by treatment with open at different dates during a period when the first pick- methyl parathion (table 2). The treatments had no effect ing ordinarily would be made. on intel'1lode length, number of internodes, height, pel' cent of bolls and squares shed, germination, per cent lint, P~~nC~;N1'o~' BOLU;OPENON INKI';(,TICIDE rrIU::\T.:\.1 E~T 10/11 10/17 1O/~4 10/31 Table 4.-Per cent of bolls and squares shed, number of ------~- ~- leaves, and dry weight per plant as affected by treatments Experillwlll 1 with toxaphene-DDT, methyl parathion, and calcium arse- Toxaphene-Din' ~·I 3l) 5·1 .5!) nate, experiment 2. Methyl pamthion 'to :33 4H ,5.5 Cheek '26 40 55 (il No.(W DHyWIC1Q111' L.S. J). @ 5% level 5 6 5 5 1NSEC'I"CIllE Smm LEAn~s I'lm PLAN'r TR~~An'mNT (%) PEHPI~ANT (G.) J';~:perillleni !2 Toxaphene-DDT ~2 41 5" 63 Toxaphene-DDT 49.6 92 30.7 Mcthyl paruthion 18 31 4.5 57 Methyl parathion 48.2 ]01 33.4 Caleium arsenate 23 41 ,51; (18 Calcium arsenate 4!J.9 78 28.6 Check 23 40 54 67 Cheek 48.6 89 31.1 L.S.D. @ 5% level 4 6 7 7 L.S.D. @ 5% level NS 8 2.0 sOO JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 55, No. :3 and the boll components seed index, lint index, boll Although there was a tendency toward reduced yield in weight, and seeds per boll. plots treated for longer durations with methyl parathion, DrscusSION.-One of the more important aspects of treatments with methyl parathion had no significant this study was the influence of certain insecticide treat- effect on yield. The number of bolls produced in cotton ments on yield and boll production. The initiation of treated with methyl parathion did not differ from the un- treatments of toxaphene-DDT at the appearance of first treated checks; however, maturity was delayed and an squares (Series 1 of Experiment 2; 12 applications) and earlier frost possibly could have impaired yield. Earliness when cotton began flowering (Experiment 1; 8 applica- was not affected by toxaphene-DDT and calcium arscnate tions, and Series 2 of Experiment 2; 9 applications) re- treatments. sulted in a significant increase in yield and boll produc- The number of leaves and dry weight of plants were tion. Treatments of toxaphene-DDT initiated whcn thc significantly increased in plots trcated with methyl para- oldest bolls were about 30 days old (Scrics 3 of Experi- thion and significantly decreased in plots trcated with Downloaded from https://academic.oup.com/jee/article/55/3/298/2207328 by guest on 30 September 2021 ment 2; 5 applications) had no effect on yield or boll pro- calcium arscnate; leaf number and dry wcight were not duction. An experiment conducted in 1959 (Brown et al. affccted by treatments with toxaphene-DDT. Plants 1961) showed an increase in boll production whcn trcat- treated with mct.hyl parathion also had a tcndcncy to mcuts of toxaphene-DDT werc initiated at the cotylc- grow t.allcrthan untreated plants; however, therc were no donar'y stage of plant development and tcrminated after significant differences among trcatmcnts with respcct to 12 and 16 weekly applications; however, there was a con- height.. current reduction in boll size and boll weight, and yield Evidence of chemical injury to plants was noted once in was not affected. Experiments at Fayettcvillc, Arkansas, plots treated with calcium arscnate in Serics 1 of Experi- showed a significant incrcasc in boll sizeowingto increased ment 2. Immature leaves in the upper portion of plants, amounts of moisture by irrigation during the growing sea- average of three leaves per plant. exhibited a small amount son (Spooner et al. 1958). Also, work on cotton by Brown of leaf burn and the margins of the leaves were crinkled. & Bryan (1961) showed that when rainfall was low or No other evidence of chemical injury was disccrniblc. poorly distributcd, irrigations increased boll size and re- Also, there was no discernible damage to cotton from the sulted in a subsequent increase in yield. At the site of the use of ground machinery. insecticide experiments conducted in 1959 and 1960, the Infestations of insects were not considered sufficicnt amount of moisture during the growing season was 1.51 during the growing season to affect the results of the ex- inches below normal in 1959 and 10.05inches above nor- periments. Also the lack of differenceswith rcspect to per mal in 1960. The "wetter" growing season in 1960 may cent shed of bolls and squares (tablcs 1 and 4) indicate have had some influence on boll size in the present study that the plant responses herein reported were caused pri- and might account in part for the differences in yield marily by the insecticides utilized in this study. when the 1959 results (Brown et al. 1961) are compared Possible adverse effects of insecticides on cotton might with those from the present study conducted in 1960.The not be discernible under certain conditions; e.g., damagc 1959results show that boll production was not influenced caused by insecticides might be compensated in part by when treatments of toxaphene-DDT wcre begun at the the protection from insects afforded by the insecticides. cotyledonary stage of plant development and terminated However, information to date strongly suggests thc pos- when plants began flowering, and no influence on boll sibility that insecticides per se influence the growth and production was noted in the present study when treat- dcvclopment of cotton. It is well known that low concen- ments of toxaphenc-DDT were initiated when the oldest trations of DDT may cause plant stimulation (Chapman bolls wcre 30 days of age. Results to date indicate that the & Allen 1948; Allen & Casida 1951). Work by Goodman effect of toxaphene-DDT on boll production are more (1955) showed that growth and fruitfulness of cotton likely to be manifested when applications of toxaphene- plants treatcd with DDT werc stimulated. A delay in DDT are confined to a period from the appearance of maturity caused by the use of certain insecticides also has first squares until thc termination of flowering. been reported; e.g., Fowler (1956) reported an increase in Treatments of calcium arsenate had no significant vegetativc growth and a later crop when cotton was effect on yield or boll production when applications were treated with parathion, and Walker & Martin (1956) initiated either at the appearance of first flowersor when concluded that Guthion appeared to delay boH matura- the oldest bolls were 30 days of age, 9 and 5 weekly ap- tion. More recent work by Brown et aI. (1961) and plications, respectively. A significant reduction in both Hacskaylo & Scales (1959) showed that certain insecti- yield and boll production occurred when calcillm arsenate cides influenced the growth and development of cotton. treatments were begun at the appearancc of first squares The accumulation of cvidcncc on the effects of insecti- (Series 1 of Experiment 2; 12 applications). Earlier work cides per se on cotton is in some respects relativcly new. by Brown et al. (1961) also showed a significant reduction Thc possible effect of any insecticide on the growth and in yield and boll production whcn calcium arsenate treat- development of cotton may be worth consideration. Also, ments were begun at the cotyledonary stage of plant work involving various solvents or adjuvants used with development and continued for 16 weekly applications; insecticides might be one of the many avenues of ap- however, other treatments of less duration had no signifi- proach to problems relative to the effects of agricultural cant effect on yield or boll production. It appears that a insecticides on cotton. deleterious effect on yield and boll production resulting from treatments with calcium arsenate is manifest only if REPF:RENCIi;S CITED treatments are applied for an exceptionally long period Anen, T. C., and J. E. Casida. 1951. Criteria for evaluat- dming the growing season. ing insecticidal phytotoxicity-aerial growth-root .Tunc 196:2 BROWN ET AL.: GROWTH OF COTTON AS AFFECTED BY INSECTICLDES 301

growth. Jour. Econ. Ent. 44(.5); 737-46. Goodman, Alan. 1955. Apparent stimulation of the growth Brown, D. A., and B. B. Bryan. ]961. Irrigation and nitrogen of X1730A cotton by an insecticide. Empire Cotton fertilization of cotton in Arka nsas. U uiversity of Growing Rev. 32: 93-101. Arkansas Bull. 648. 56 pp. Hacskaylo, Joseph, and A. 1. Scales. ]959. Some effects of Brown, Lamar C., Charles Lincoln, R. E. Frans, and B. A. Guthion alone and in combination with DDT and of Waddle. 1961. Some effects of toxaphene-DDT and a dieldrin-DDT mixture on growth and fruiting of the calcium arsenate on growth and development of cot- cotton plant. Jour. Ecou. Eut. 52(3): 396-8. ton. Jour. Bcon. Ent. 54(2); 300-11. Spooner, A. E., C. E. Caviness, and W. I. Spurgeon. 1958. Chapman, R. K., and T. C. Allen. ]948. Stimulation and sup- InBuence of timing of irrigation on yield, quality, and pression of some vegetable plants by DDT. Jour. fruiting of Upland cotton. Agron. Jour. 50: 74-77. Beon. Bnt. 4](4): 6Hi-23. Walker, J. K., Jr., and D. F. Martin. 1956. Comparison of Fowler, H. D. ]9.56. Some physiological cffects of attack by certain insecticides for boll weevil and bollworm con-

whiteBy (IJemisia gossypi1Jerda) and of spraying para- trol. Paper presented at the Annual Meeting of the Downloaded from https://academic.oup.com/jee/article/55/3/298/2207328 by guest on 30 September 2021 thion on cotton in the Sudan Gezira. Empire Cotton Southwestern Branch, Entomological Society of Growing Rev. 33: 288-99. America.

The Effects of Percussion on Insect Pests of Grain1

S. W. BAIl_~~Y, Divisl:on of Entomology, Commonwealth Scientific and Indu.stria.l Research Organization, Canberra, A.C. T., A u.stralia

ABSTRACT requirements. However, the method has not been adopted The effects of percussion on grain and on insect pests of grain because existing machines cause excessive breakage of the have been examined. It was found that adults and unprotected grain. It is claimed that this breakage can be avoided by immature stages of the granary weevil (Sitopltilus granarius (1,,)) running the machines at a reduced speed at which free- were killed by a relatively small amount of impact forces. To kill living grain pests are destroyed (Cotton 1958), but as the immature stages living within the grains required the use of most important grain pests have immature stages that fO['cesintense enough to cause excessive breakage of the grain. live within the individual grains, destruction of the free- It is suggested that the survival of immature stages within the living insects only is of little value unless the grain is to be grnin was caused by the physical support provided by the grain, consumed immediately after treatment. As a measure to which prevented severe Battening of the insect. be applied with the object of prolonging the storage life of grain or of meeting quarantine requirements in overseas The use of physical methods of controlling insect pests markets such treatment is of no value. in stored foodstuffs and other products is attractive, as An examination of the literature has not revealed any no residual toxicity hazards are introduced and the in- study of the percussive forces required to kill adult insects are unlikely to develop any significant resistance to sects and their immature stages living within the grain on such methods. the one hand, and those causing breakage of sound grain Many physical agents have been suggested, especially on the other. The present work was undertaken to deter- various forms of heat, light and sound, and more recently mine these forces in the hope that it would be possible to irradiation by gamma rays. l\1:ost of these methods have separate the two effects. so far proved ineffective or impracticable, only heat hav- PRELIMINAHY CONSIDERATIONs.-The "Entoleter" is ing been used on an industrial scale (e.g., Cotton 1958). referred to as a centrifugal machine and it is clear that Heat, howe vcr, has the drawback of slow penetration some authors have thought that centrifugal force is re- through the bulk of material being treated and partly for sponsible for its effectiveness. An examination of the this reason it has not proved very popular. Slow penetra- machine shows that material being treated falls between tion may be overcome by thc use of high-frequency clectric two rapidly spinning discs. Centrifugal force Causes it to fields (e.g., Thomas 195~), but the cost of the necessary move to the periphery of the disc where it is struck by equipment and the running costs are prohibitive for most steel impactors; it then strikes the steel casing and falls stored products. into the hopper below. The material, and any insects in it, The only physical control method in regular large~scale are therefore subject to centrifugal force followed by two use in industry employs the effects of centrifugal force impacts. and percussion, and machines such as the "Entoleter" Centrifugal force v2/gr cannot exceed that due to the have been readily accepted by industries manufacturing peripheral speed of the rotor discs. At the maximum granular and powdery products such as flour. Their ac- speed this is ~oofeet per second on a disc of 8-inch radius. ceptancc is based on their effectiveness (Cotton & The maximum centrifugal force produced is, therefore, Frankenfeld 194~. Parkin] 955), reliability, and simplic- approximately ~,OOO g's. In practice this figure is not ity of operation; they require no chemicals or supervision, likely to be even approached as there will be a great deal need only to be switched on, and are continuous-flow of slip between the disc and the material being treated. devices, thereby fitting in readily with flow production Furthermore, the radial flow of material is in no way methods such as are used in flour mills. restrained. ~Whatever force is realized, will only act on an These advantages would apply equally to the grain- individual insect for a fraction of a second. handling industries which at present have to rely on 1 Accepted for publication October 11, 1961. This paper WfiS endorsed by chemical control with its attendant limitations and labor Dr, Lyman S. Henderson.