European Journal of Sustainable Agroecosystems

Aphids (Hemiptera: Aphididae) pose a serious threat to the cultivation of Brassica oleracea L. worldwide, causing significant economic losses and requiring sustainable management strategies. This field study evaluated the efficacy of botanical biopesticides from neem (Azadirachta indica), garlic (Allium sativum), chilli (Capsicum annuum) and pongamia (Millettia pinnata) to control aphid populations on cabbage while conserving beneficial arthropods. The experiment was performed in a randomized complete block design with ten treatments and four replications during the 2024 winter season (November 2023–March 2024). Treatments included four formulations of botanical biopesticides, a standard insecticide control, and an untreated control. Results showed that the neem-based biopesticide caused a 78.4% reduction in the aphid population by mid-season, significantly (p<0.05) higher than other botanical treatments. Neem treated plots showed minimum damage to non-target organisms with 72.3% crop protection efficiency. Botanical biopesticide treatments conserved populations of ladybird beetles (Coccinella septempunctata), lacewings (Chrysoperla carnea) and parasitoids with densities 41% higher than synthetic insecticide plots. Neem treatment significantly improved physiological parameters of plants like chlorophyll content and biomass accumulation. Application of neem biopesticide significantly enhanced the marketable cabbage yield by 38.7% (18.5 t/ha) as compared to the untreated control (13.2 t/ha). The combined use of botanical biopesticides with ecological practices was economically viable, environmentally sustainable and reduced dependence on synthetic pesticides by 85 percent. The results suggest that botanical biopesticides can be sustainable tools in cabbage production for integrated pest management (IPM) approaches, contributing to environmental conservation with the objective of food security and agricultural productivity.