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ThesisItem Open Access Avoidable crop losses, Economic Threshold Level and management of Helicoverpa armigera (Hübner) in chickpea(Punjab Agricultural University, Ludhiana, 2018) Akanksha; Ravinder SinghField studies were conducted for two years during rabi 2016-17 and 2017-18 to determine the crop losses, to establish economic threshold level (ETL) and to evaluate the efficacy of various integrated pest mangement (IPM) modules for the management of Helicoverpa armigera (Hübner) in chickpea. The avoidable yield loss of 26.27 per cent was observed in chemical method as compared to 19.59 per cent in mechanical exclusion method over unprotected method. The avoidable crop losses due to H. armigera in chickpea var. PBG 7 was recorded to be 73.50 per cent by insect density method with larval population of six larvae per meter row length. The correlation coefficient for the larval infestation level and the per cent pod damage was significantly positive. However, significantly negative correlation was observed between larval infestation level per meter row and seed yield. On the basis of regression analysis and gain threshold, the EIL and ETL were determined to be 2.086 and 1.56 larvae per meter row, respectively. Among the different IPM modules tested for two years, to test the bioefficacy against H. armigera in chickpea, the treatment with three sprays of indoxacarb 14.5 SC @ 66 g a.i. ha-1 was found to be significantly superior over all other biointensive modules and untreated control but was at par with novaluron 10 EC @ 37.5 g a.i. ha-1 > chlorantraniliprole 18.5 SC @ 25 g a.i. ha-1 > emamectin benzoate 5 SG @ 11g a.i. ha- 1. Results of the study revealed that significantly lowest larval population of zero larvae per meter row, lowest pod damage of 1.41 per cent, highest seed yield of 1950 kg ha-1 and highest C:B of 1:6.9 were found in treatment with three sprays of indoxacarb 14.5 SC @ 66 g a.i. ha-1.