Incremental cost benefit ratio of different insecticides and bio-pesticides against chilli thrips (Scirtothrips dorsalis Hood) on chilli crops (Capsicum annum L.)

Abstract

The present investigation entitled “Studies on population dynamics of thrips (Scirtothrips dorsalis Hood) in chilli (Capsicum annuum L.) and its management through eco-friendly approaches in changing climate scenario” was carried out during the kharif seasons of 2022-2023 and 2023-2024 at the Student’s Instructional Farm, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.). The primary objective of the study was to evaluate the effectiveness of various chemical and bio-pesticide treatments against thrips infestation in chilli under changing climatic conditions, along with assessing their economic viability through Incremental Cost Benefit Ratio (ICBR) analysis. Across both years, the treatment with Imidacloprid 17.8 SL @ 0.2 ml/l proved to be the most effective, recording the highest mean yields and ICBR. In 2022-23 with an ICBR of 1:7.20. In the subsequent year, it maintained its superiority with a yield of 105.35 q/ha, ICBR of 1:22.17. Among other synthetic options, Acetamiprid 20 SP, Spinosad 45 SC and Thiamethoxam 25 WG also exhibited substantial effectiveness, with ICBRs ranging from 1:17.44 to 1:21.71 and moderate yield enhancements. Ecofriendly treatments such as Neem Oil (1500 ppm), Beauveria bassiana and Metarhizium anisopliae showed lower effectiveness in comparison to chemical treatments but still offered environmentally safer alternatives. Neem Oil and B. bassiana resulted in mean yields between 85-92 q/ha and ICBRs around 1:7.4-1:9.5 across both seasons. Although M. anisopliae performed the least effectively, with yields around 80 q/ha and the lowest ICBR values (1:3.72-1:3.79), it still outperformed the untreated control.