Evaluation of Neem-Based Biopesticides in Controlling Aphid Population in Brassica juncea: A Review

Abstract

The management of aphid infestations, particularly by Lipaphis erysimi, remains a major challenge in the cultivation of Brassica juncea (Indian mustard), significantly affecting yield and oil quality. Conventional synthetic insecticides, although effective, pose serious environmental and health concerns, while also leading to pest resistance and the elimination of beneficial organisms. Neem (Azadirachta indica)-based biopesticides have gained prominence as eco-friendly alternatives due to their bioactive compounds such as azadirachtin, nimbin, and salannin, which act through antifeedant, growth-inhibiting, oviposition-deterring, and repellent mechanisms. The role of neem-based biopesticides in controlling the aphid population in Brassica juncea. Current scientific evidence on the efficacy of neem-derived formulations, including neem oil, neem seed kernel extract (NSKE), and commercial products, against mustard aphids under laboratory, greenhouse, and field conditions. Neem products consistently show a reduction in aphid populations ranging from 60% to 80%, along with minimal impact on natural predators and parasitoids. Comparative analyses highlight that neem can offer equivalent control to synthetic pesticides when applied properly, especially in early infestation stages. Despite these benefits, issues such as variability in azadirachtin content, short residual activity, and lack of standardisation across commercial formulations present significant limitations. Moreover, the requirement for repeated applications and gaps in farmer awareness affect large-scale adoption. Prospects for neem-based pest control lie in the development of advanced formulations with extended field stability, molecular studies on insecticidal pathways, and better regulatory mechanisms for product quality. Long-term field studies are also needed to assess ecological impacts and yield sustainability. With the support of policy initiatives and extension services, neem has the potential to become a vital component of Integrated Pest Management (IPM) in mustard farming, contributing to safer and more sustainable agricultural systems.