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ThesisItem Open Access Population dynamics, effect of intercropping in relation to sowing time and efficacy of insecticides against major insect-pests of chickpea(CCSHAU, 2019) Chitralekha; Yadav, G.S.A two year study (2015-16 and 2016-17) on effect of different management practices such as date of sowing, intercropping and insecticides application and weather variables on population dynamics of Helicoverpa armigera, Spodoptera exigua and Autographa nigrisigna attacking chickpea crop in Haryana, India was conducted at CCS Haryana Agricultural University, Hisar. Residues of lambda-cyhalotrin and novaluron in chickpea pods and grains at recommended and double the recommended dose were also estimated. It was found that date of sowing had significant effect on population of these pests. The larval population of all the three pests was comparatively higher in late sown crop (i.e. sowing done on 15th and 30th November) than in early sown crop (i.e. sowing done on 15th and 30th October). Population of these pests in all the sowing dates generally reached their peaks during the 12th Standred Meteorological Week (SMW) after which there was decline in population. Population of all these pests exhibited significant positive correlation with temperature and sunshine hours during both the the years. Pooled data of the two years indicated that intercropping chickpea with other crops such as coriander, mustard, linseed and barley harboured lesser population of these pests than when intercropped with other crops. Minimum larval population of H.armigera (3.05 larvae/meter row length), S. exigua (1.37 l/mrl) and A. nigrisigna (1.69 l/mrl) were observed in intercropping combinations of chickpea + coriander, whereas maximum in chickpea + fenugreek combinations, being 4.15, 1.73 and 2.04 l/mrl. Among the various insecticides evaluated against these pests, chlorantraniliprole 18.5 EC at 25 g a.i./ha and novaluron 10 EC at 37.5 g a.i./ha proved to be most promising insecticides in reducing larval population, pod damage and increasing grain yield. Residues of lambda-cyhalothrin in chickpea pods and grains at double the recommended dose i.e. 50 g a.i./ha were below maximum residue limit (MRL) while that of novaluron i.e. 75 g a.i./ha above MRL.