Sustainable pest management: synergistic mechanisms of mesoporous silica‐mediated Bacillus thuringiensis delivery in Plutella xylostella control

BACKGROUND: Bacillus thuringiensis (Bt) has emerged as a promising biopesticide globally due to its target specificity, environmental safety, biodegradability, and lack of residual toxicity and a low likelihood of inducing insect resistance. However, its practical application faces critical limitations due to UV sensitivity and short-field persistence, constraining broader commercial development. RESULTS: /g). The binding process of the two is mainly dominated by hydrogen bonds, and hydrophobic interaction is synergistic. Compared to raw Bt powder, MSN-Bt significantly enhanced insecticidal efficacy against Plutella xylostella (diamondback moth), offering UV protection and reduced degradation to maintain bioactivity and stability. Anti-washing experiments show that its wettability, adhesion and rain washing resistance are improved. At the same time, the highest cumulative release rate can reach 97.12% under alkaline conditions. MSN-Bt further induced reactive oxygen species (ROS) production in the insect midgut, exacerbating damage to epithelial cells and microvilli, thereby accelerating disruption of the digestive system. Bioassays confirmed that MSN-Bt effectively minimized cabbage leaf damage caused by P. xylostella, whereas pure MSN showed no pesticidal activity. Moreover, MSN and the composites did not significantly affect the non-target organisms. CONCLUSION: MSN can serve as eco-friendly and efficient carriers for biological pesticides, offering a novel strategy for the stable delivery of Bt and enhancing its practical application in sustainable agriculture. © 2026 Society of Chemical Industry.