Sandhu, Inderpal SinghCheema, Rupinder Singh2023-12-112023-12-112023Cheema, Rupinder Singh (2023). Biorational management of the major lepidopterous pests of cabbage and cauliflower (Unpublished Ph.D. Dissertation). Punjab Agricultural University, Ludhiana, Punjab, India.https://krishikosh.egranth.ac.in/handle/1/5810202508Chemical pesticides are commonly used to control major lepidopterous pests of cabbage and cauliflower. This approach often results in several negative consequences such as pesticide residues, resistance, pest resurgence and environmental pollution. Therefore, finding alternative and more environment friendly management methods is crucial. To address these issues, this study conducted in rabi seasons of 2020-2021 and 2021-2022 to explore alternative management tactics for major lepidopterous pests like Pieris brassicae, Plutella xylostella, and Spodoptera litura that are safer for the environment. Among the plant products, azadirachtin 0.03%, NSK Powder, turmeric powder and pongamia oil were found effective up to 5 days when applied to cabbage and cauliflower crops against P. brassicae, P. xylostella, and S. litura. However, the standard check spinosad 2.5 SC @ 3 ml/litre recorded maximum per cent reduction and remained effective up to 7 days. Mustard oil, sesame oil, castor oil, and pongamia oil recorded the highest population of natural enemies on cabbage and cauliflower. Cauliflower and cabbage yields were significantly higher with azadirachtin 0.03% @ 25 ml/litre, which was at par with spinosad 2.5 SC. In microbial agents, Bacillus. thuringiensis var kurstaki 0.5% WP (800 and 600 g/acre) was the most effective, followed by Beauveria bassiana 1.0% WP (1.75 kg/acre) against P. brassicae, P. xylostella, and S. litura on both cabbage and cauliflower crops. M. anisopliae and B. bassiana had the highest population of natural enemies on cabbage and cauliflower. Moreover, cauliflower and cabbage yields were significantly higher with spinosad 2.5 SC @ 240 ml/acre, which was at par with B. thuringiensis var kurstaki 0.5% WP (800 and 600 g/acre). Among the various homemade mixtures of natural products, Brahmastra @ 50 ml/litre was the most effective, followed by Agniastra @ 50 ml/l against P. brassicae, P. xylostella, and S. litura on both cabbage and cauliflower up to 5 days. Brahmastra @ 40 ml/litre and desi cow's urine 100% and 500 ml/litre had the highest population of natural enemies on both cabbage and cauliflower crops. Additionally, cauliflower and cabbage yields were significantly higher with Brahmastra @ 50 ml/litre. However, the standard check spinosad 2.5 SC recorded the maximum yield. Among the various non-chemical modules, tested at Fazilka and Ludhiana during rabi season of 20212022, azadirachtin 0.03% + B. thuringiensis var kurstaki 0.5% WP (Module 1) was the most effective against P. brassicae, P. xylostella, and S. litura on both cabbage and cauliflower crops. However, the farmer practice (Chlorantraniliprole 18.5%) recorded the highest per cent reduction, which was at par with spinosad 2.5 SC. The population of natural enemies were at par in all three non-chemical modules on both cabbage and cauliflower crops. Cauliflower and cabbage yields were significantly higher with Module 1. However, the farmer practice recorded the maximum yield.EnglishThesis