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Studies on present status of white grub, holotrichia serrata (fabricious) (coleoptera; scarabaeidae) in Belagavi District and its management
(UAS Dharwad, 2013) P. S. Tippannavar; R. R. Patil
Studies carried out in Belagavi district of Karnataka during 2011 and 2012 on species composition, population dynamics, behaviorual pattern of adult white grub, loss estimation, both laboratory and field evaluation of entomopathogens and newer chemical insecticides revealed that Holotrichia serrata and Holotrichia fissa were the dominant species in irrigated and rain fed ecosystem respectively. Adult emergence of H. serrata commenced from 7th Meteorological Standard Week (MSW) (February) and continued upto 18th MSW (May), whereas in rainfed ecosystem adult emergence of H. fissa was recorded from 14th MSW (April) and continued upto 22 MSW (May). Adult trapping with various sources indicated that neem (Azadirichta indica) was the best source to trap the adults of H. serrata. Studies on host range indicated the spread of white grub population from sugarcane to other crops namely, groundnut, soybean, maize, paddy, turmeric and vegetables under kharif and wheat, sorghum and bengalgram under rabi conditions. Fungal pathogens evaluated under laboratory conditions against second instar H. serrata grub revealed that the combination of Metarhizium anisopliae and Beauuveria bassiana @ 4x109 conidia/g was most effective but on par with M. anisopliae and B. bassiana alone @ 4x109 conidia/g. Similar to laboratory conditions field evaluation of fungal pathogens for two years (2011-2012) revealed that higher dosages of fungal pathogens @ 25 kg/ha and FYM @ 125 kg/ha were more effective in reducing grub population significantly. Field evaluation of novel insecticide revealed that significant superiority of imidacloprid + fipronil 80 WG @ 1000 g/ha and on par with rynaxypyr 4G @ 20 kg/ha, lambda cylohothrin 5 EC @1500 ml/ha and imidacloprid 17.8 SL @1000 ml/ha were found superior to other insecticides by recording higher larval mortality. Among the five sugarcane genotypes screened both under protected (M. anisoplieae) and unprotected conditions against H. serrata grub. CoM 265 variety emerged as tolerant followed by CoSnk 03632.
Open Access
Studies on survey, seasonal incidence, varietal screening and management of major insect pests of pigeonpea in the northern transitional zone of Karnataka
(UAS Dharwad, 2013) Bandi Sanjay Maruti; L. Krishna Naik
Investigation on survey, seasonal incidence, varietal screening and management of insect pests of pigeonpea in the northern transitional zone of Karnataka was carried out at MARS, UAS, Dharwad during 2011 to 2013. The pest spectrum of pigeonpea in the northern transitional zone included 31 insect pests belonging to orders lepidoptera, hemiptera, coleopteran, diptera, thysanoptera, hymenoptera and orthroptera. The survey studies revealed that the highest population of insect pests on pigeonpea was recorded in Haveri followed by Dharwad and lowest in Belgaum district. The peak activity of pod borer, Helicoverpa armigera (Hubner) was observed during 48th week (November) for both the years of study. The maximum population of plume moth was noticed at 47th (November) and 48th week (November) during first and second year. The influence of different dates of sowing on pest incidence revealed that the early sown pigeonpea crop (1st week of June, 3rd week of June and 1st week of July) registered lower incidence of pest and higher grain yield. The field screening of pigeonpea cultivars for their tolerance to pest damage revealed that ICP-8863 registered least inflorescence damage by flower webber, Maruca vitrata (Geyer). The cultivar, BSMR-736 suffered with lesser damage by leaf webber (Grapholita critica Meyr.) and gram pod borer (H. armigera). The incidence of bud weevil, Ceuthorhynchus asperulus (Faust), pod bugs (Anoplocnemis phasiana (Fabricius), Riptortus pedestris (F.) and Clavigralla gibbosa Spinola), plume moth, Exelastis atomosa (May.) and pod fly, Melanagromyza obtusa (Malloch) was least on cultivar, GC-11-39. The efficacy of different insecticides tested revealed that indoxacarb 14.5 SC (0.5 ml/l), spinosad 45 SC (0.3 ml/l), emamectin benzoate 5 SG (0.2 g/l) and flubendiamide 480 SC (0.1 ml/l) were highly effective against H. armigera. Among the entomopathogens tested, HaNPV (250 LE/ha) and Bacillus thuringiensis (2.0 kg/ha) were found superior in suppressing the population of H. armigera.
Open Access
Studies on defoliators and stemfly pests of soybean and their management
(UAS Dharwad, 2013) Prabhu Nayaka; R. H. Patil
Investigations were carried out on different insect pests of soybean at ARS, Bailhongal and MARS, UAS, Dharwad, Karnataka during kharif, 2010-11 and 2011-12. Survey was under taken in four districts of northern Karnataka viz., Dharwad, Belgaum, Haveri and Bagalkot during kharif 2010 and 2011. Among districts surveyed, Belgaum and Bagalkot were identified as hot spots for stem fly while Dharwad and Belgaum were identified as hot spots for defoliators by recording higher incidence. The surveillance in fixed plot study indicated the highest incidence of Melanagromyza sojae during 36th and 37th Meteorological Standard Week (10.10 and 15.00%, respectively). The population of Spodoptera litura ranged from 2.50-3.45 larvae/meter row length, Thysanoplusia orchalcea fom 1.05-1.82 l/mrl and Spilarctia oblique from 1.30-2.15 l/mrl and activity of natural enemies observed on 15 days after sowing. Correlation studies between insect pests and weather parameters revealed that, rainfall had negative correlation (r = 0.55) and maximum temperature (r = 0.71) had positive correlation with S. litura and M. sojae. Seed dressing with thiamethoxam 70 WS @ 3.0 g/kg seed + foliar spray of thiamethoxam 25 WG @ 0.5 g/l at 20 days after sowing proved its superiority over other treatments in managing stem fly by recording high seed yield of 25.64 and 24.42 q/ha during 2010 and 2011, respectively. Among the insecticide, flubendiamide 480 SC 0.2 ml/l was found to be the most effective in managing leaf eating caterpillars by recording highest seed yield of 23.95 q/ha. The simulation studies revealed that 25 per cent defoliation at 20 DAG did not significantly affect the seed yield while at 60 days after germination it was significantly educed the seed yield. Among the genotypes screened for two years PS-1466 and PK-1042 were found resistant to stem fly and high yielding. While JS-335 and Dsb-11 susceptible to high yielding and defoliation as per max-min and min-max method.
Open Access
Crop habitat diversification, planting time and plant geometry for management of chilli pests
(UAS Dharwad, 2013) Sujay Hurali; R. S. Giraddi
Investigations on effect of different cropping systems, planting time and planting geometry; influence of different genotypes on chilli pests and evaluation of new molecules and their effect on natural enemies were carried out during 2008-09 and 2009-10 at the Main Agricultural Research Station, UAS, Dharwad. Lowest incidence of sucking pests, leaf curl index, larval population of Helicoverpa armigera (Hub.) fruit damage with higher yield and net returns were obtained from different cropping systems when compared to sole chilli. The coccinellids and chrysopids were found in large numbers in different cropping systems (intercropping, trap cropping and border/ barrier cropping). Significantly lower level of sucking pest, leaf curl index, larval population of H. armigera and fruit damage was observed in the crop with July 15th planting and 90x60 cm spacing. The interaction effect among date of planting and different spacing was significant. Dry chilli yield was significantly highest with July 15th planting and 90x60 cm spacing (4.21 q/ha) followed by July 30th and 90x60 cm (4.09 q/ha) and July 15th and 75x45 cm (3.81 q/ha). Similar pattern of treatment significance was observed in case of predator population also. The cultivars viz., Sarpan hybrid, Tejashwini and Sankeshwar recorded relatively lower sucking pest population, leaf curl index, larval population of H. armigera and fruit damage when compared to popular varieties viz., Byadagi kaddi and Byadagi dabbi which exhibited these phonological characters at lower levels. Thiamethoxam 25WG @ 1 g/l, abamectin 1.8EC @ 0.5 ml/l, diafenthiuron 50 WP @ 0.75 g/l were found highly effective against sucking pests. Against H. armigera, novaluron 10 EC @ 0.75 ml/l, emamectin benzoate 5SG @ 0.4 g/l and spinosad 45SC @ 0.3 ml/l were found quite promising. Significantly highest yield (4.65 q/ha) recorded in diafenthiuron 50 WP @ 0.75 g/l with higher net returns (Rs 22,661/ ha).
Open Access
Effect of weather parameters on the incidence of major insect pests and their natural enemies in few selected kharif and rabi crops
(UAS Dharwad, 2013) Poornima Matti; Shekharappa
Field studies were carried out to address the effect of weather change on the incidence of insect pests during kharif and rabi 2011-12 and 2012-13 at the Main Agricultural Research Station, Dharwad. Forecasting model for pod damage in greengram depicted minimum temperature and rainy days at four weeks lead time is consistently significant positively associated. Higher shoot fly eggs in kharif sorghum were noticed with increase in both minimum temperature and morning RH. At three week before, incidence of deadheart had positive relationship with evening RH and significant negative association with maximum temperature. Forecasting model for per cent defoliation in soybean at two weeks prior showed that morning RH is consistently significant negative association in normal sown crop. However, rainfall had significant positive relationship with foliage damage. Forecasting model for per cent pod damage due to Helicoverpa armigera in chickpea at four weeks before showed minimum temperature is consistently highly significant and negatively associated. Forecasting models developed for deadheart due to shoot fly in M-35- 1, at three week before in late sown crop and minimum temperature only had highly significant positive correlation, whereas, in DSV-4, evening RH had highly significant positive relationship. Forecasting model for aphids per 5cm central twig in safflower showed that solar radiation at four weeks prior is consistently significant and negatively associated. In intercrop, Bt, spinosad, emamectin benzoate and RPP spray efficacy on lepidopteran pests was higher with rise in evaporation, solar radiation and maximum temperature. Whereas, Beauvenia bassiana showed higher efficacy with rise in morning RH and minimum temperature. Validation of forecasting model for per cent deadheart due to shoot fly infestation on rabi sorghum in late sown condition resulted lead week three model gave minimum error (3.66) and performed better in 2008 than 2009 and 2010 years with high R2 value of 0.71.
Open Access
Baseline susceptibility and compatibility of pesticides against spodoptera litura (fabricius) and plutella xylostella (linnaeus) in cabbage and their safety to beneficial insects
(UAS Dharwad, 2013) Satish; K. Basavana Goud
Susceptible laboratory strains of Spodoptera litura and Plutella xylostella were used to establish baseline susceptibility for seven insecticides, median lethal concentration of the tested insecticides varied from 0.016 to 62.25 ppm for S. litura. Chlorantraniliprole (0.016 ppm) was highly toxic while lambda-cyhalothrin (62.25 ppm) and spinosad (62.15 ppm) were least toxic. Emamectin benzoate was highly toxic (0.009 ppm) and lambda-cyhalothrin (10.22 ppm) was least toxic to susceptible strain of P. xylostella. Hirebagewadi population of S. litura exhibited greater levels of resistance to the tested insecticides followed by Garag and Madihal populations. Irrespective of insecticides, P. xylostella from Kolar population recorded higher level of resistance followed by Bengaluru and Dharwad population. Endosulfan proved to be safer to Trichogramma chilonis, followed by chlorantraniliprole. Spinosad recorded least mortality to the grubs of Chrysoperla zastrowi sillemi (50.00%) in diet contamination method. Grub mortality of C. z. sillemi ranged from 0.00 to 93.33% at 48 h after treatment in contact residual toxicity method. Emamectin benzoate was highly safer with 13.33 % mortality to adults of C. z. sillemi. All the insecticides tested were toxic to adults of Oomyzus sokolowskii. Endosulfan (46.67%) was relatively safer to Apis cerena followed by Chlorfenapyr (60.74%). Chlorfenapyr was highly safer to Bombyx mori and Samia cynthia ricini. The combination of emamectin benzoate+hexaconazole was more effective in suppressing both lepidopteran pests and Alternaria leaf spot on cabbage. Pesticides at field recommended doses showed no phytotoxicity injury on cabbage crop. Indoxacarb and flubendiamide persisted for longer time (21 days) against S. litura while flubendiamide and chlorantraniliprole against P. xylostella persisted for a longer period of 28 days compared to all other tested insecticides.
Open Access
Biology of cryptolaemus montrouzieri mulsant and management of grapevine mealybug, maconellicoccus hirsutus (green)
(UAS Dharwad, 2013) P. M. Prasanna; R. A. Balikai
The investigation on “Biology of Cryptolaemus montrouzieri Mulsant and management of grapevine mealybug, Maconellicoccus hirsutus (Green)” were conducted during 2009 to 2011. The C. montrouzieri took 3.68, 4.68, 5.80 and 5.58 days to complete first, second, third and fourth instar by feeding 3.02, 7.52, 47.03 and 83.75 mealybugs, respectively. Predatory adult male and female survived for 58.18 and 62.48 days by feeding 38.00 and 42.97 mealybugs, respectively. Among the prediction models developed, the model LW1=68.03 - 0.6X3 (X3 = morning relative humidity) could be used by substituting current week’s weather data, to predict mealybug population a week ahead. Seven predators four, two and one from coccinellids, dipterans and lepidopteran, respectively and twelve hymenopterans parasitoids were recorded on grape vine mealybug. The laboratory experiment showed that, biology and feeding potential of first, second, third and fourth instar and adult male and female of C. montrouzieri was more when fed on second instar than third instar mealybugs. With respect to biorational studied under laboratory and field conditions, the efficacy of neem (NSKE and neem oil) based botanicals mixed with adjuvants with or without entomopathogens were showed higher per cent mortality of different instars of mealybugs as compared to other botanicals tested. Whereas, the different insecticides tested on mealybug were found more effective, among them bifenthrin, imidacloprid 70 WG, imidacloprid 17.8 SL and dichlorvos were highly effective in recording per cent mortality on mealybugs under laboratory and field condition. Regarding grape fruit yield, the imidacloprid 70 WG recorded highest fruit yield (37.92 t/ha), followed by bifenthrin (37.21 t/ha) and imidacloprid 17.8 SL (36.21 t/ha). Among the biorationals, the application of NSKE @ 5% + Dhanuvit @ 1 ml/l (29.82 t/ha), neem oil @ 2% + FORS @ 5 ml/l + M. anisopliae @ 2.0 g/ l (29.69 t/ha) and neem oil @ 2% + Dhanuvit @1 ml/l (29.51 t/ha) registered highest fruit yield.
Open Access
Studies on insecticide resistance in leafhopper, amrasca biguttula biguttula (ishida) in bt cotton
(UAS Dharwad, 2013) Sagar D.; R. A. Balikai
Studies on insecticide usage, insecticide resistance and diversity in leafhopper, Amrasca biguttula biguttula (Ishida) across major cotton growing districts of Karnataka and nitrogen induced susceptibility on leafhopper population were under taken at the Department of Agricultural Entomology, College of Agriculture, Dharwad during 2011-2013. The insecticide usage pattern varied greatly between and within the locations indicating no definite insecticide usage pattern among the major cotton growing districts of Karnataka. In all the major cotton growing districts of Karnataka except Mysore, monocrotophos and imidacloprid formulations were the primary choices of insecticides for management of sucking pests in Bt cotton. Among the nine insecticides bioassayed, monocrotophos registered higher LC50 value during both the years followed by imidacloprid, thiamethoxam, acephate and acetamiprid while, the lower LC50 value was registered by fipronil followed by clothianidin. The botanical, azadirachtin 1500 ppm recorded higher LC50 value as compared to other nine insecticides. Leafhopper population of Raichur and Yadgir districts recorded higher LC50 values to almost all insecticides under study, while Mysore district’s leafhopper population recorded lower LC50 values to all insecticides bioassayed. Higher mixed function oxidase enzyme activity was noticed in the leafhopper population of Raichur followed by Yadgir, while lower activity was noticed in Mysore district population. The six district’s leafhopper COI gene sequences were confirmed as A. biguttula biguttula cytochrome oxidase subunit I (COI) gene. COI sequence analysis showed higher similarity among the leafhopper population of major cotton growing districts of Karnataka. The cotton leafhopper population of all the six districts was taxonomically identified as A. biguttula biguttula. The incidence of leafhopper and leaf nitrogen content increased with the increase in the nitrogen dosages. The toxicity results indicated that there was no such striking difference in LC50 values among leafhopper population as influenced by dosages of nitrogen.
Open Access
Investigations on Seasonal Incidence and Management of Mirid Bug, Poppiocapsidea Biseratense Distant Bt Cotton
(UAS Dharwad, 2013) Vinaykumar M. M.; P. S. Hugar
Investigations on seasonal incidence and management of mirid bug, Poppiocapsidea biseratense (Distant) in Bt cotton was carried out at MARS, UAS, Dharwad during 2011-12 and 2012-13 indicated that the incidence of mirid bug started during 38th Meteorological Standard Week (0.17 bug/10 squares) and reached maximum population 5.74 bugs at 47th MSW. Thereafter, the population declined to 3.12, 1.25, 0.79, 0.57 and 0.15 bugs between 48th and 52nd standard weeks of November and December month. During roving survey the highest population of mirid bug was observed in Haveri (average of 8.26 and 6.80 bugs/10 squares) whereas, the lowest incidence was recorded in Bagalkot district with an average of 4.02 and 3.20 bugs during 2011-12 and 2012-13, respectively). In fixed spot survey, the peak incidence of the pest was observed during November II fortnight (8.80 bugs/10 squares) in Dharwad. But, in Belgaum and Haveri district the peak incidence registered (6.20 and 12.2 bugs/10 squares) during October II fortnight, respectively. The effect of different dates of sowing on incidence of mirid bug revealed that the early sown cotton crop (June 1st and June 15th) had registered lowest mirid bug population with highest GOB and yield. The late sown crop suffered much with the increased incidence followed by lowest yield. Field screening of cotton cultivars for their reaction to mirid bug damage revealed that, Chiranjeevi (HxH BG-II), RCH-2Bt and Bunny (NBt) appeared as less prone to mirid bug attack with highest yield. While, the lowest yield was recorded in Nathbaba, DHB-915 and DHH-11 which were more prone to mirid bug. The morphological characters of cotton plant viz., gossypol gland, trichome density, and trichome length were exhibited positive and leaf thickness had negative correlation with mirid bug incidence. The amount of phenol, gossypol and tannin had a negative and total sugar had a positive correlation with incidence of mirid bug. The efficacy of different components tested against mirid bug revealed that the fipronil 5 SC @1 ml/lit found to be superior followed by acephate 75 WP @ 1.0 g/lit in suppressing the mirid bug population.

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