Devendra PrasadGopal Krisna2024-07-112024-07-112000https://krishikosh.egranth.ac.in/handle/1/5810211817Investigation was carried out during winter 1998-99 in the insectory of Entomology Department. Birsa Agriculture University Kanke Ranchi for the management of major insect pests associated with cauliflower under the agro climatic conditions prevailing around Ranchi. Seven insect pests viz diamond back moth, Plutella xylostells (L); aphids, lipaphis erysimi (Kalt)Myzus persicae (Sulz) cabbage caterpillar ,pieris brassicae (L) cabbage semilooper,plusia orichalcea (fab)painted bug, Bagrada hilaris (B) and Bihar hairy caterpillar,Splosoma oblique (Wlk) were observed on cauliflower ,In which diamond back moth abd aphids were categorixed as najor pests. Temperature and relative humidity play an important role for the population buildup of insect pests. Ambient maximum minimum and average temperature ranging from 22.0 to 27.5 degree, 6.64 to 12.00 and 14.89 to 20.0degree c favored the population buildup and multiplication of diamond back moth and aphids. The significance of relative humidity ranging from 51.70 to80.50 per cent (max) , 30.86 to 53.14 per cent (min) and 41.40 to 63.79 per cent (average) was also associated with the population buildup of diamond back moth. However, the range of maximum relative humidity (54.40 -80.50 %), minimum relative humidity (30.85-53.14%) and average relative humidity (41.40-63.80%) were slightly increased for development of aphids. All the insecticides were found to be equally effective against diamond back moth and two species of aphid (L.erysimi and M.persicea) Chlorpyriphos emerged to be very effective synthic insecticide in reducing the population of diamond back moth, L.erysimi and M.persicea ranging from 70.17 to 90.67 percent ,86.67 to 94.53 percent and 80.10 to 93.77 percent respectively .Among biopesticides flufenoxuron (cascade 10DC @ 400ml/ha) appeared to be the most effectiveinsecticide responsible for minimizing the higher population of diamond back moth (65.95-86.49%) L.erysimi (67.00-9400%) and M. persicea (47.00-92.17%) Better results were also obtained with the application of B.t(Dipel) and cartap hydrochloride (caldan). Intercropping with dissimilar hosts were responsible for suppressing the incidence if insect pests. Reduction in the population of diamond back moth,L.erysimi and M persicae ranging from 42.40 to 91.82 percent ,35.06 to 81.25 per cent and 24.97 to87.52 per cent were obtained when coriander was intercropped with cauliflower. The corresponding figures in case of garlic ranged from 54.49 to 90.90 per cent ,33.51 to79.17 per cent and 22.76 to 63.70 per cent respectively .The population of these pests were increased slightly when mustard was intercropped with cauliflower. The highest yield of cauliflower was obtained with the application of chlorpyriphos followed by cypermethrin. However the yield obtained in different treatments except cauliflower .However +mustard and untreated control were nit different significantlyEnglishThesis