Nanopesticides for managing primary and secondary stored product pests: Current status and future directions

The preservation of agricultural commodities during storage is critical for ensuring food security and minimizing post-harvest losses. Both primary storage pests such as Callosobruchus maculatus, Callosobruchus chinensis, Sitophilus weevils, Rhyzopertha dominica, and Trogoderma granarium, and secondary storage pests like Tribolium castaneum cause significant damage to stored products, resulting in substantial economic losses. Traditional pest control methods, including chemical insecticides, face limitations due to environmental concerns and pest resistance. Consequently, nanoparticle-based insecticides are being extensively suggested as a promising alternative. This review analyzes the available literature on the efficacy of nanoparticles (NPs) against primary and some secondary storage pests. Green synthesis methods using plant extracts and other biological sources are highlighted for the production of environmentally friendly NPs. Studies demonstrate that NPs of alumina, carbon, silica, silver, copper, zinc oxide, nickel oxide, titanium dioxide, nano zeolite, as well as chitosan and polymers exhibit significant insecticidal activity against a variety of pests, in some cases surpassing mortality rates caused by traditional insecticides at recommended dosages. Structural, biochemical and molecular studies reveal that NPs induce oxidative stress, disrupt cellular homeostasis, and cause structural damage in pests. Histopathological evaluations indicate specific organ-related toxicity, emphasizing the need for comprehensive biosafety assessments. Additionally, the integration of NPs with conventional insecticides shows enhanced pest control efficiency, although challenges remain in standardizing synthesis methods and evaluating long-term environmental impacts. This review highlights the potential of NPs in sustainable pest management and underlines the importance of ongoing research to optimize specific formulations for specific groups of pests and ensure safety.