Silica-Based Nanodelivery Systems Loaded with Matrine for the Brown Planthopper Green Control and Rice Growth Promotion

Botanical pesticides have been shown to be an appropriate technology for crop protection as they present a high level of safety to ecosystems and biodiversity. However, most botanical pesticides have defects of slow action, short persistence, and instability during pest control, which restrict their further development and application. Currently, nanodelivery systems have displayed great promise to solve these deficiencies. Herein, we used mesoporous silica nanoparticles (MSNs) as nanocarriers loaded with botanical pesticide matrine and coated with chitosan to prepare matrine nanoparticles (MaNPs) for controlling Nilaparvata lugens (Stål) on rice (Oryza sativa L.). The results showed that MaNPs possessed excellent stability and high biosafety to nontarget organism tadpoles. Foliar-sprayed 25 mg/L MaNPs decreased the populations of adult and nymph N. lugens and particularly resulted in a 55.1% decrease in nymph N. lugens population and a 74.8% increase in rice shoot biomass, as compared to infected control. Moreover, MaNPs exhibited superior control performance for N. lugens reproduction than conventional matrine pesticides, which was due to the induced higher levels of chemical defense-related compounds in rice plants. Altogether, chitosan-functionalized silica nanodelivery systems could be an effective and eco-friendly nanocarrier for loading botanical pesticides to prepare nanopesticides in sustainable chemistry and promote their green applications in pest management.