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ThesisItem Open Access POPULATION DYNAMICS, VARIETAL SCREENING AND MANAGEMENT OF THRIPS, Thrips tabaci Lindeman INFESTING Bt COTTON 2915(JAU, JUNAGADH, 2019-08) Patel Kaushikbhai Ramubhai; Patel Kaushikbhai RamubhaiInvestigations on population dynamics, varietal screening and management of thrips, Thrips tabaci Lindeman infesting Bt cotton were carried out under field condition during Kharif 2018 at Junagadh Agricultural University, Junagadh. For the management of thrips, different ten varieties /genotypes were screened and different combinations of nitrogenous fertilizer doses and soil as well as foliar application of insecticides were evaluated. The incidence of thrips, T. tabaci was commenced from 3 rd week of July and continued till third week of November having a single peak (27.96 thrips /three leaves) during 3rd week of August. Thrips population had negative significant impact due to maximum temperature [r = -0.570*] and significant positive correlation to rainfall [0.768*], morning relative humidity [0.562*] as well as evening relative humidity [0.574*]. Bright sunshine hours were negatively, wind speed, and minimum temperature were positively correlated with the incidence of thrips population but results were not significant. The lowest thrips incidence was recorded in GJHV-541 (3.57 thrips /3 leaves) and GJHV-540 (4.41) genotypes of Bt cotton and was categorized as resistant (R). The highest thrips population was recorded in G.Cot.-460 (11.84), G.Cot.-18 (12.40) and G.Cot.-12 (13.55) variety and it was categorised into susceptible (S) against the pest.….....………….……………………………………………………….………….Abstract Based on both the sprays and pooled over periods, thrips can be effectively managed by nitrogenous fertilizer application of 240 kg /ha and soil and foliar application of fipronil 0.3 G + spinetoram 11.7 SC. Interaction of fertilizer to insecticidal application was found effective in treatment combination [(240 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)] followed by [(240 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)]. While, [(360 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)] and [(360 kg N /ha) + (carbofuran 3 G + spinosad 45 SC)] treatments performed less in giving satisfactory protection to Bt cotton crop against thrips. The highest {2906 kg /ha} seed yield was harvested in the plots treated with [(240 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)] followed by [(240 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)] {2831}. As far as the per cent increase of yield over control concerned, maximum yield loss can be avoided with spray application of [(240 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)] {92.09}, followed by [(240 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)], [(300 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)], [(240 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)] and [(240 kg N /ha)+ (carbofuran 3 G + spinosad 45 SC)]. The highest Incremental Cost Benefit Ratio (ICBR) was calculated from the plots treated with [(240 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)]. But in overall effectiveness of nitrogenous fertilizer and insecticides application [(240 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)] found most effective (first rank) followed by N1I1 [(240 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)] > N1I4 [(240 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)] > N2I2 [(300 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)] > N2I4 [(300 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)] > N2I3 [(300 kg N /ha) + (carbofuran 3 G + spinosad 45 SC)] > N2I1 [(300 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)] > N1I3 [(240 kg N /ha) + (carbofuran 3 G + spinosad 45 SC)] > N3I4 [(360 kg N /ha) + (fipronil 0.3 G + spinosad 45 SC)] > N3I1 [(360 kg N /ha) + (carbofuran 3 G + spinetoram 11.7 SC)] > N3I2 [(360 kg N /ha) + (fipronil 0.3 G + spinetoram 11.7 SC)} and N3I3 [(360 kg N /ha) + carbofuran 3 G + spinosad 45 SC)] against T. tabaciThesisItem Open Access BIOLOGY, SEASONAL INCIDENCE AND MANAGEMENT OF RED SPIDER MITE, Tetranychm urticae KOCH IN OKRA 1998(JAU, JUNAGADH, 2015-06) SIDDHAPARA MUKESH RAMJIBHAI; Dr. V.R. ViraniAn investigations were carried out on biology and management of okra red spider mite, T. urticae at Junagadh Agricultural University, Junagadh, Gujarat during 2013-14. Studies on biology of red spider mite, T urticae revealed that both the sexes passed through five stages viz., egg, larva, protonymph, deutonymph and adult with a short resting period known as quiescent. The eggs were laid singly, mostly on the lower surface of leaves. The eggs were smooth, soft, round and translucent white. The incubation period was 3.37 ± 1.07 days with 91.06 ± 3.84 per cent eggs hatching. The average larval, nymphochrysalis, protonymphal, deutochrysalis and deutonymphal periods were 1.78 ± 0.58 and 2.67 ± 0.66, 0.65 ± 0.36 and 0.70 ± 0.34, 2.44 ± 0.57 and 2.83 ± 0.75, 0.74 ± 0.42 and 0.96 ± 0.42, 2.20 ± 0.77 and 2.70 ± 0.88 days for male and female, respectively. The matured deutonymph remained in quiescent stage (teliochrysalis) for 0.80 ± 0.27 days in female. This stage was only found in female T. ^rticae whereas in case of male it was absent. The total developmental period was longer in female (10.66 ± 1.28 days) as compared to male (7.81 ± 1.40 days). The average pre oviposition, oviposition and post oviposition periods were 3.00 ± 1.56 and 1.80 ± 1.13 5-55 ±1.61 and 8.37 ± 1,22, 2.30 ± 1.08 and 3.23 ± 1.04 days in unmated and mated females, respectively. The fecundity for unmated and mated female was 26.15 ± 7 74 and 78.37 ± 13.26 eggs. The male lived shorter (10.10 ± 1.65 days) than the mated (13.40 ± 1.92 days) and unmated (10.85 ± 2.54 days) females. The total life period occupied by T. i^rticae 17.91 ± 2.55 days in male and 24.06 ±2.14 days in female. Seasonal incidence of T. urticae revealed that the mite population observed from 2"'' week of July to throughout crop life. The higher mite population was noticed during 2"'' week of August to 2"*' week of October with peak during month of September, 2013 and October, 2014. The mite activity was declined when last picking was completed. Predatory mites and predatory beetle activity were started from 4"' and 5"^ week of July. Wind speed had highly significant negative correlation while, minimum temperature, moming, evening and mean relative humidity and vapour pressure had negative correlation with mite population during kharif 2013-14.ThesisItem Open Access MANAGEMENT OF MAJOR INSECT PESTS OF MUSTARD 1949(JAU,JUNAGADH, 2014-11) R. L. Kalasariya; Dr. K. L. RaghvaniInvestigations on Management of major insect pests of mustard were carried out at College Farm, College of Agriculture, Junagadh Agricultural University, (Gujarat) during Rabi season of the year 2012-13 and 2013-14. Studies on population dynamics of major insect pests of mustard revealed that incidence of aphid commenced in 3"^^ week of December during 2012-13 and 2013-14. Its population increased, thereafter, gradually and reached to its peaks with 4.92 and 4.26 aphid index in 3'^ and 5^^ week of February during 2012-13 and 2013-14, respectively. Correlation of aphid population with minimum temperature (r = -0.611 ) and evening relative humidity (r = -0.518*) were found significantly negative dunng 2012-13, while significant positive correlation (r = 0.502 ) was noticed with minimum temperature during 2013-14. The incidence of sawfly started in 3'^'' week of December and attained a peak i.e. 3.72 and 3.59 larvae/plant during and 2"'' week of January during 2012-13 and 2013- 14, respectively. The sawfly exhibited highly significant negative correlation with maximum (r = -0.637** and -0.702**), minimum (r = -0.623 and -0.625 ) and mean temperature (r = -0.712** and -0.692**) during 2012-13 & 2013-14, respectively. While, significant positive correlation (r = 0.506*) was observed with bright sunshine hours during 2013-14. The incidence of leaf webber was noticed in d'" week of December and attained a peak activity of 6.89 and 7.88 larvae/plant during the 4' week of February during both years. Leaf webber exhibited significant negative correlation with minimum temperature (r = -0.503*), evening (r = -0.596 ) and mean relative h^idity (r = -0 502*) while significant positive correlation (r - 0.545 ) was found with bright sunshine hours during 2012-13. A significant positive co^elafion was also found with minimum temperature (r = 0.498*) and evening relative humidity (r - 0.509 ) during 2013-14. The incidence of painted bug started in 3'" week of December in both years and attained first peak during the P' week of January i.e. 6.75 bugs/plant. Whereas, second peak i e 7.05 bugs/plant was noticed during the 3 week of Januaiy during 2012-13. Incase of 2013-14, the population of painted bug attained a firct t • 6.95 bugs/plant during 2"' week of Januao- and second pel Te 5 9^ hrf,"' dunng 3' week of Februaiy. Painted bug exhibited highly significant neuat assoemtton wtth maximun. (r = -0.755- and -0.790"). minit^^umTr = T743- -0.726 ), mean temperature (r = -0.847 and -0 789**1 wherenc cjI,-#- correlation (r = -0.498- and -0.497-) was obsen-ed with evaporati™ ^th ' (-1.590?:„d';Sti:et"ve;" anr^"^ respectively. Whereas, negatively high (-1.4828 and -1 2178^ temperature, (1.2479) direct effect were noticed by minimum temperature wind high temperature, respectively, on mustard sawflv nnnniaf,-rx„ -r,. ' and mean Lcinperature wmH o j —® temperature, respectively, on mustard sawfly population Tht^'^JT mean (-2.0215) exerted negatively very high direct effect while mean ^^i^hve humidity and moming relative humidity (1.2839) exhibited negative aL ("1.1341) iefnffelcute nocne pio.pe.u l6a.ti6o3n7 9b,u i5l.d5-1u1p1 o,f 3 l.e0a0f 9W4e babnedr ,2 r.e2s9pe6c4t iwveelrve Pnoh.fv Ppj^'h^® h^i'gghh ddiirreecctt temperature, minimum temperature, moming and evenin^"^^ , maximum respectively, while, mean temperature (-10.893) and mean r^laf humidity wweerree eexxhhiibbiitteedd nneeggaattiivvee aanndd vveerryy hhiigghh ddiirreecctt effect whlmf^!^^ ^^midity ((-"55..117722Q9^) dS^^olflO.'"' Of PaiSb":^™ beetle wPa's™ n"ogt2ic0e1d3 p"o1s4it,i dvierleyc vte erfyf ehcitg ho f(2 m.e0a9n63 t)e amnpde rhaitguhr et la nd nn i • ladybird minimum temperature exhibited negatively very high direct cff,- !' J®^P®®hvely while population. The minimum temperature and mean S f ^ negative (-1.1270) and positive (1.3670) high direct influence onTo f ^'^erted mus ard sawfly respectively. The direct influence of m^^ positively very high (2.2219) while, mean temperature a^^ u ""P'^^hire shoL J exerted negatively very high (-2.0822) and high (-1 35on T sunshine hour of leaf Webber. The mean temperature and mLn briif''''' po^ moderately negative (-0.8748) and positive (0.6957) dire« eS oxhibltS up of painted bug in mustard. ettect on population build Among the different insecticidal schedules tested for tt, • eornplex of mustard showed that schedule 4 (flonicamid 0 02 Z "gainst pest 0.014 per cent, azadirachtin 0.15 per cent and aceohafe + r SubendarTiH found most effective against mustard aphid and painted"h ° per cemf (thiamethoxam 0.006 per cent, emamectin benzoate 0.0025 per® ***''"• ^^hedule 3 kgflia, chlorpynphos + alphamethrin 0.055 per cen^ I fUevi I sawfly and leaf Webber of mustard. found superior against 6116.17.22 4p piern ceenrt ryt^eltd rtnrerieSaste o^vlerf cponrtreo^l rwhpil^e^ utnp'r:o'te'e?t edX''r' was es"fhowS kg/ha wTihthe e1c6o0n.4o mpiecrs coefnditf ifnecrreenats ien s(eocvteirci dcaoln tsrcohle dautl e'r grain viain kgd,, return ?/ha 29674 and ICBR 1:6.27 was obti^h^ed f°°® ne^ yield obtained from schedule 3 i.e. 1218 kgdia S schedule 4 ^/ha 26566 as well as ICBR 1:6.28 was foutd^^i ~ and I''ThesisItem Open Access POPULATION DYNAMICS, YIELD LOSS AND FIELD EFFICACY OF CHEMICAL INSECTICIDES AGAINST Lipaphis erysimi (Kalt.) IN MUSTARD 2569(JAU,JUNAGADH, 2018-06) Bavisa R. V.; Dr. G. M. ParmarPresent investigations on population dynamics, yield loss and field efficacy of chemical insecticides against Lipaphis erysimi (kalt.) in mustard were carried out at Main Oilseeds Research Station, Junagadh Agriculture University, Junagadh during Rabi season, 2016- 17 Aphid population commenced from 4th Week After Sowing (WAS) [1st week of December (49th Standard Meteorological Week- SMW)] with aphid index 0.14 and reached to peak (4.9 aphid index/plant) at 15th week after sowing i.e., 3rd week of February (8th SMW). Thereafter, decreasing trend was observed up to 2nd week of March (11th SMW) as crop reached to its maturity. Relatively higher activity (1 to 4.90 aphid index/plant) was observed during 2nd week of January to 4th week of February (2nd to 9th SMW) i.e. 9th to 16th WAS. However, at the maturity of the crop, the negligible population with more number of winged aphids was observed on green stem of mustard. The correlation matrix indicated that the aphid population had highly significant positive correlation with evaporation (r = 0.627**) and significant and positive relation with minimum temperature (r = 0.514*). Aphid population had positive correlation with bright sunshine hours (0.349), wind speed (0.470), maximum temperature (0.405), mean temperature (0.471), and growing degree day (0.471) while negative relationship with morning relative humidity (-0.452), evening relative humidity (-0.334) and mean relative humidity (-0.423). The avoidable loss in yield of mustard due to mustard aphid, L. erysimi estimated 60.70 per cent. The yield recorded in protected plot was 1559 kg/ha which ………………………………………………………...………….………….Abstract showed 191.94 % yield increase over control while unprotected plot recorded 825 kg/ha. Testing the bio-efficacy of insecticides, thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015% flonicamide 0.02% and imidacloprid 0.005% successfully checked the incidence of aphid. The next best treatments were clothianidin 0.003%, dimethoate 0.03% and thaicloprid 0.024%. Among the tested insecticides, the highest aphid index was noted in plots treated with dinotefuran 0.008 % and it was less effective treatment among all the evaluated insecticides and was at par with fipronil 0.05 % and imidacloprid 40% + fipronil 40% @ 0.03%. The order of effectiveness of synthetic insecticides was thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015 % > flonicamide 0.02% > imidacloprid 0.005 % > clothianidin 0.003 % > dimethoate 0.03% > thiacloprid 0.024 %> imidacloprid 40% + fipronil 40% @ 0.03% > fipronil 0.05 % > dinotefuran 0.008 %. The maximum yields was found from the plots treated with thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015% (1690 kg/ha) followed by flonicamide 0.02% (1439 kg/ha), imidacloprid 0.005% (1279 kg/ha), and clothianidin 0.003% (1259 kg/ha). The plots treated with the dinotefuran 0.008% (842 kg/ha) recorded the lowest yields. The chronological order of various insecticidal treatments in comparison to control based on yield (kg/ha) was: thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015% > flonicamide 0.02% > imidacloprid 0.005% > clothianidin 0.003% > dimethoate 0.03% > thiacloprid 0.024% > imidacloprid 40% + fipronil 40% @ 0.03% > fipronil 0.05% > dinotefuran 0.008%. The maximum net realization was obtained from the treatment of thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015 % (39590 Rs/ha) followed by flonicamide 0.02% (30303 Rs/ ha) and imidacloprid 0.005% (24383 Rs/ha).The highest ICBR (16.93) was calculated from the plots treated with imidacloprid 0.005% followed by dimethoate 0.03% (15.79) and proved to be more economical insecticide, while fipronil 0.05% (1.10) recorded lower ICBR and proved to be the least economical insecticidal treatment In nutshell, based yield and economics; imidacloprid 0.005% was found to be the most effective and economical insecticidal treatment followed by dimethoate 0.03%, flonicamide 0.02%, thiamithoxam 12.6% + lambda cyhalothrin 9.50% @ 0.015%. Thus, it can be recommended for the management of aphid in mustard.ThesisItem Open Access SEASONAL INCIDENCE, YIELD LOSSES AND FIELD EFFICACY OF INSECTICIDES AGAINST SUCKING PESTS OF SUMMER GROUNDNUT 2520(JAU,JUNAGADH, 2018-03) Bajaniya Mehulkumar Dhirajlal; Dr. V. R. ViraniExperiments were conducted on “Seasonal incidence, yield losses and field efficacy of insecticides against sucking pests of summer groundnut’’ at Instructional Farm, College of Agriculture, Junagadh Agricultural University, Junagadh during summer, 2016. Studies on seasonal incidence of the major sucking pests of groundnut, variety TG-37, revealed that the aphid population initiated from the 1st week after sowing i.e. the fourth week of February with 0.48 nymph/ 3 leaves/ plant. The population of the pest increased gradually from the 1st to 7th week after sowing and reached the peak population (5.44 nymphs/ 3 leaves/ plant) in the 7th week after sowing coinciding with the 2nd week of April. However the second peak of population (4.64 nymphs/ 3 leaves/ plant) was observed in the 8th WAS i.e. the 3rd week of April. Aphid population was found to occur throughout the crop period. The population declined gradually towards the end of the crop period and remained at zero level at the time of harvest i.e. the 13th week after sowing. The correlation matrix indicated that the population of aphids exhibited significant positive correlation with maximum temperature, mean bright sunshine hours and significant negative correlation with morning relative humidity and wind velosity. The population of whitefly (0.00 whiteflies/ 3 leaves/ plant) appeared from the 1st WAS i.e. the fourth week of February and start to emergence remained active throughout the crop period. The pest population increased gradually and reached the first peak level of 4.56 whiteflies/ 3 leaves/ plant during the 8th WAS coinciding with the second week of April. Later on, it was found to decline drastically (0.12 whiteflies/ 3 leaves/ plant) at the time of harvest of groundnut. Correlation coefficient values stated that the population of whitefly exhibited positive correlation with maximum temperature, and bright sunshine hours. The results indicated that the population of thrips (1.12 thrips/ 3 leaves/ plant) appeared from the 1st WAS i.e. the 4th week of February and remained active throughout the flowering period. The pest population increased gradually and reached a peak level (8.24 thrips/ 3 leaves/ plant) during the 8th WAS coinciding with the second week of March. The population declined gradually during the successive weeks and reached zero level at the time of harvest of groundnut. The correlation coefficient values indicated that the population of thrips exhibited positive correlation with maximum temperature, bright sunshine hours and significant negative correlation with morning relative humidity. Significantly higher yield of 1600 kg/ ha was recorded from the plots protected against the sucking pests of groundnut, while yield of 1240 kg/ ha was recorded from the unprotected plots. The increase in yield in protected plots over unprotected plots was found to be 360 kg/ ha. This showed 22.60 per cent increase in yield and 29.03 per cent avoidable loss. The results from the two sprays on aphids have revealed that flonicamid 0.015 per cent, imidacloprid 0.005 per cent, dinotefuran 0.0010 per cent and thiamethoxam 0.01 per cent were found to be the most effective insecticides. The results of relative efficacy of eleven different insecticides revealed that flonicamid 0.015 per cent and acetamiprid 0.008 per cent gave very good results against the whiteflies. In accordance with the results obtained from two sprays, spinosad 0.015 per cent and fipronil 0.01 per cent were the most effective of the insecticides against thrips population. Flonicamid 0.015 per cent recorded the highest yield (1742 kg/ha) and highest cost benefit ratio (1:84.32) was also obtained from the treatment of dimethoate 0.03 per cent.ThesisItem Open Access BIONOMICS, POPULATION DYNAMICS AND MANAGEMENT OF APHID, Hyadaphis coriandri DAS INFESTING FENNEL 2416(JAU,JUNAGADH, 2017-08) Kanjiya Ravi Rameshbhai; Dr. K. D. ShahKey words: Fennel, aphid, Hyadaphis coriandri, coccinellid predators, bionomics, population dynamics, varietal screening, chemical control. Investigations on bionomics, population dynamics and management of fennel aphid, H. coriandri were carried out under laboratory condition at Department of Entomology and Instructional farm, College of Agriculture, Junagadh Agricultural University, Junagadh during Rabi 2015-16. For the management of aphid, different nine varieties /genotypes were screened and different nine insecticides were evaluated against the pest. The aphid nymphs were moulted four times before attaining the adult stage. Average body length, width, antennal length & cornicle length of first, second, third and fourth instar nymphs were 0.51 + 0.02, 0.30 + 0.01, 0.24 + 0.01 & 0.03 + 0.01 mm; 0.69 + 0.02, 0.36 + 0.02, 0.34 + 0.01 & 0.05 + 0.01 mm; 0.92 + 0.03, 0.45 + 0.02, 0.46 + 0.02 & 0.10 + 0.01 mm and 1.13 + 0.03, 0.60 + 0.06, 0.54 + 0.02 & 0.15 + 0.01 mm, respectively. Average body length, width, antennal length and cornicle length of adult aphid were 1.41 + 0.02, 0.67 + 0.03, 0.68 + 0.02 and 0.21 + 0.01 mm, respectively. The average developmental period of first, second, third and fourth nymphal instar nymphs were 1.44 + 0.51, 2.44 + 0.51, 2.48 + 0.51 and 1.48 + 0.51 days, respectively. The total nymphal duration was 7.19 + 1.60 days. The mean longevity of adult aphid was observed to be 10.14 + 1.49 days with an entire life span of 17.33 + 1.91 days. The pre-reproductive, reproductive and post-productive periods were found to be 1.33 + 0.48, 6.95 + 1.36 and 1.86 + 0.73 days, respectively. The fecundity was observed to be 30.67 + 8.41 nymphs per female and the intrinsic rate of single female per day was an average of 4.41 + 1.61 nymphs /day. The activity of aphid, H. coriandri was commenced from 2nd week of February and remained up to 3rd week of March having peak during 4th week of February in fennel crop. Simultaneously, higher population of coccinellids was observed during 4th week of January to 3rd week of March and showed significantly highly positive correlation with aphid population. The lowest aphid incidence was recorded in GF-2 (0.87 A.I. /plant) variety of fennel and was categorized as highly resistant variety. Genotype RF-125 (1.73) found to be highly susceptible (HS) against aphid incidence. The highest coccinellids (5.87 coccinellids /plant) and seed yield (985.19 kg/ha) were recorded from the variety GF-2. The results of nine tested insecticides on aphid, H. coriandri can be effectively managed by spray application of dimethoate 0.003%, flonicamid 0.015% and clothianidin 0.025%. Acetamiprid 0.008%, imidacloprid 0.005% and thiamethoxam 0.01% could also be exhibited satisfactory protection but only up to 50 per cent reduction over control. Thiacloprid 0.021%, difenthiuron 0.05% and dinotefuran 0.01% did not provide satisfactory protection against aphid to fennel crop. Among the different insecticides, dinotefuran 0.01% was found the safer treatment against coccinellid predators as highest number of coccinellids (7.35) was recorded in this treatment. Dimethoate recorded more than 75 per cent reduction in coccinellids population over control and such it was categorized as “harmful”. The per cent increase over control was recorded maximum seed yield loss could be avoided with spray application of flonicamid 0.015% followed by dimethoate 0.03%, clothianidin 0.025%, acetamiprid 0.008%, imidacloprid 0.005% and thiamethoxam 0.01%. Even though the yield and yield increase over control was very low in the treatments i.e., dinotefuran, difenthiuron and thiacloprid, they increased the yield in the range of 24.08 to 33.15 per cent. The highest Incremental Cost Benefit Ratio (ICBR) was calculated from the plots treated with dimethoate (1:54.64). In overall effectiveness of insecticides, flonicamid 50 WG @ 0.015% found most effective (first rank) followed by dimethoate > imidacloprid > acetamiprid > clothianidin > difenthiuron > dinotefuran > thiamethoxam > thiacloprid against H. coriandri.ThesisItem Open Access POPULATION DYNAMICS, YIELD LOSS AND EVOLUTION OF SOME NEWER INSECTICIDES AGAINST SESAME LEAF WEBBER, Antigastra catalaunelis duponchel(JAU,JUNAGADH, 2012-07) R.M. HINSU; V.N. PATELThesisItem Open Access ECO-FRIENDLY MANAGEMENT OF BRINJAL SHOOT AND FRUIT BORER, Leucinodes orbonalis GUENEE THROUGH ORGANIC MANURES AND BIO-PESTICIDES(2013-12) PATEL MAHESHKUMAR LABHUBHAI; BHARODIA R. K.Investigations were carried out on eco-friendly management of brinjal shoot and fruit borer, Leucinodes orbonalis Guenee through organic manures and bio-pesticides at Instructional Farm, College of Agriculture, Junagadh Agricultural University, Junagadh during Rabi 2011 and 2012. During the study, brinjal shoot and fruit borer, Leucinodes orbonalis Guenee was the major pest found infesting this crop in Junagadh area of Gujarat State. Studies on eco-friendly management of brinjal shoot and fruit borer, L. orbonalis through organic manures revealed that maximum (75%) requirement of the nitrogen by the crop provided through the neem cake combined with the inorganic fertilizers recorded the shoot infestation, fruit infestation on number and weight basis. While, FYM recorded the maximum population of natural enemies. Also, maximum yield of healthy brinjal fruits was recorded in the treatment where 75 per cent of the recommended dose of nitrogen was provided through neem cake. Considering the effect of organic manures on morphological characters of brinjal, the treatment where 50 per cent of the required nitrogen was provided through poultry manure and remaining through in inorganic form recorded the maximum plant height, number of leaves per plant, number of flowers per plant and number of fruits per plant. The studies on relationship between pest infestation and morphological characters of brinjal revealed that plant height, number of leaves per plant, number of flowers per plant and ABSTRACT Abstract number of fruits per plant exhibited the negative correlation with the shoot infestation, fruit infestation on number and weight basis. While, all the morphological characters showed positive correlation with shoot infestation, fruit infestation on number and weight basis. Study on bio-efficacy of bio-pesticides against brinjal shoot and fruit borer, L. orbonalis revealed that profenophos (40%) + cypermethrin (4%) 0.04 per cent, NSKE 5 per cent and neemazal 0.005 per cent were found most effective against the pest with minimum shoot and fruit infestation. The treatment of spinosad 0.01 per cent, emamectin benzoate 5 per cent and cartap hydrochloride 0.1 per cent were the next effective treatments against this pest. Significantly maximum yield of healthy brinjal fruits (29051 kg/ha) was recorded in the treatment of profenophos (40%) + cypermethrin (4%) 0.04 per cent, neemazal 0.005 per cent (28002 kg/ha) and NSKE 5 per cent (27261 kg/ha). The treatments with spinosad 0.01 per cent (26520 kg/ha), emamectin benzoate 5 per cent (25779 kg/ha) and cartap hydrochloride 0.1 per cent (25039 kg/ha) were included in the next group of effective treatments. The economics of two spray applications of profenophos (40%) + cypermethrin (4%) 0.04 per cent gave the highest net return followed by neemazal 0.005 per cent. Rest of the treatments viz, NSKE 5 per cent, spinosad 0.01 per cent, emamectin benzoate 5 per cent and cartap hydrochloride 0.1 per cent were the next economic treatments against this pest. Considering the cost benefit ratio of these treatment, neemazal 0.005 per cent and profenophos (40%) + cypermethrin (4%) 0.04 per cent gave the maximum cost benefit ratio. Thus, looking to the effectiveness and economics of different organic manures and bio-pesticides applied against major insect pests of brinjal, it can be concluded that maximum nitrogen requirement of the crop provided through the organic manures followed by two sprays of profenophos (40%) + cypermethrin (4%) 0.04 per cent, neemazal 0.005 per cent or NSKE 5 per cent were economic for the control of brinjal shoot and fruit borer, L. orbonalisThesisItem Open Access POPULATION DYNAMICS, YIELD LOSSES AND MANAGEMENT OF THRIPS, Scirtothrips dorsalis Hood INFESTING CHILLI(2013-10) SHITOLE TUSHAR DADASAHEB; Patel V. N.Key words: Chilli, thrips, leaf curling, losses, management and residue The investigation on population dynamics, yield losses and management of thrips, Scirtothrips dorsalis Hood infesting chilli was carried out at two different location i.e. farmer’s field (Village Devlki, Taluka: Vadia, Dist: Amreli) in North Saurashtra Agroclimatic Zone during 2011 and at Junagadh (South Saurashtra Agroclimatic Zone) during 2012. The population dynamics of thrips, S. dorsalis Hood infesting chilli crop and the leaf curling appeared was studied at different two location (in North Saurashtra Agroclimatic Zone and in South Saurashtra Agroclimatic Zone) during Kharif 2011 and 2012. The results revealed that the thrips infested the chilli crop right from seedling stage to maturity stage of the crop. The thrips infestation commenced in 31st standard week and the pest population multiplied very fast from 33rd to 42nd standard week and reached at peak 84.13/ 3 twig. Thereafter, pest population was decreased. The chilli leaf curling was also appeared with thrips and increased fats from 14 per cent to 81 per cent with increased thrips population. The higher activity of thrips on chilli crop at both the location was found during 41st to 45th standard week. The weather parameters supported high multiplication of the thrips on chilli were maximum temperature 35℃ to 37.1℃ and minimum temperature 18.35℃ to 22.15℃, maximum relative humidity 57.5 per cent to 70 per cent and minimum relative humidity 26 per cent to 31.5 per cent, wind seed 2.65 to 4.35 km/h, bright sun shine hours 7.35 to 9.65 h/day and evaporation rate 5 to 5.6 mm/day with no rain. The correlation study indicated that increased thrips population on chilli crop was highly positive with maximum temperature, while significantly positive correlation with evaporation rate and bright sunshine hours. However, the correlation of thrips population with minimum relative humidity was highly negative, while significantly negative correlation with maximum relative humidity. Non-significant negative correlation between thrips population and minimum temperature and rainy days was exhibited. Correlation between thrips population and leaf curling severity was existed highly significant. The relationship of appearance of leaf curling and the thrips infesting chilli was studied by three different angles. The percentage of leaf curling (severity) was increased with increased number of thrips per plant. The coefficient of correlation between number of thrips and percentage of leaf curling was strongly positive. After the insect were eliminated by the insecticidal spraying, the growth of plants was normal and without curling within 20 day. While the plant kept as control (untreated) were continued with thrips and pronounced leaf curling recorded. The cell sap of leaves having severe and typical symptoms of leaf curling was inoculated on the healthy tender leaves of potted healthy plants. Leaf curling symptoms not produced in the sap inoculated plants (protected). This result indicated that insect born virus was not responsible for producing the leaf curling in chilli. The experiments on qualitative and quantitative losses caused by thrips, S. dorsalis infesting chilli were conducted at two different location (in North Saurashtra Agroclimatic Zone and South Saurashtra Agroclimatic Zone) during Kharif 2011 and 2012. The result revealed that 62.58 per cent leaf curling, 26.34 per cent plant height, 28.50 per cent branches, 33.39 per cent length and 11.01 per cent width of fruit (green chilli) and 62.83 per cent length and 64.04 per cent width of leaf were reduced due to infestation of the thrips in chilli. Further quality of green chilli i.e. appearance, shape, luster of green chilli was also detoriated. The quantitative (yield of green chilli) losses was ranged 11333 kg/ha (289.77%) to 10911 kg/ha (299.39%) with an average 11122 kg/ha (294.41%). The avoidable loss was 74.34 per cent to 74.96 per cent with average of 74.65 per cent. Bioefficacy of the twelve insecticides was evaluated against thrips, S. dorsalis infesting chilli on farmer’s field. Three application of the insecticides was given at fifteen day interval. The result revealed that significantly the highest reduction in thrips population (7.33 thrips/3 twig) and leaf curling (13.29 per cent) was recorded on chilli crop treated with spinosad 0.009 per cent followed by profenophos + cypermethrin 0.044 per cent, abamectin 0.003 per cent, imidacloprid 0.005 per cent, profenophos 0.05 per cent, acetamiprid 0.008 per cent, diafenthiuron 0.05 per cent and indoxacarb 0.0145 per cent. The maximum thrips population 52.22/3 twig and degree of leaf curling 56.97 per cent was recorded on untreated plants (control). The significantly maximum yield (15278 kg/ha) of green chilli with 229.34 per cent increased over control was recorded from the crop treated with spinosad 0.009 per cent followed by profenophos + cypermethrin 0.044 per cent, abamectin 0.003 per cent and imidacloprid 0.005 per cent. The highest monitoring net return of ` 212780/ha was also recorded from spinosad 0.009 per cent followed by profenophos + cypermethrin 0.044 per cent (` 182220/ha), abamectin 0.003 per cent (` 161660/ha), imidacloprid 0.005 per cent (` 160000/ha), acetamiprid 0.008 per cent (` 145000/ha) and profenophos 0.05 per cent (` 140560/ha). The six insecticidal spray schedule having three to eight insecticidal applications at 30, 20, 15, 12, 10 and 8 days interval were evaluated against chilli thrips. The schedule 6 having eight insecticidal applications at eight day interval starting from 40 day after transplanting was found most effective against chilli thrips and leaf curling. The maximum yield 10875 kg/ha with the highest net monitoring return was also received by the schedule 6. The insecticides applied in schedule 6 were (i) Polytrin C (profenophos 40% + cypermethrin 4%) 0.044 per cent, (ii) abamectin 0.003 per cent, (iii) imidacloprid 0.005 per cent, (iv) spinosad 0.009 per cent, (v) Polytrin C (profenophos 40% + cypermethrin 4%) 0.044 per cent, (vi) acetamiprid 0.008 per cent, (vii) spinosad 0.009 per cent and (viii) imidacloprid 0.005 per cent. The residue of imidacloprid 0.005 per cent, abamectin 0.003 per cent and cypermethrin 0.004 per cent (Polytrin C 0.044%), spinosad 0.009 per cent and profenophos 0.04 per cent was below maximum residue limit (MRL). The residue of these insecticides in/on green chilli was below its maximum residue limit (MRL). But the residue of acetamiprid 0.008 per cent (0.346 mg/kg) was slightly above the maximum residue limit (0.20).
