Superior Leaf Deposition and Subsequent Uptake: Nanocarrier Boosts Cyproflanilide for Enhanced Pest Control.

Chemical pesticides remain indispensable for crop protection, but inefficient delivery and overapplication lead to resistance and environmental risks. Cyproflanilide is a novel meta-diamide insecticide active against a broad range of agricultural pests. Here, we developed a star polycation (SPc) nanocarrier to enhance cyproflanilide delivery and insecticidal activity. Cyproflanilide and SPc self-assembled through hydrogen bonding and van der Waals forces, reducing cyproflanilide particle size from 374 to 154 nm. Complexation with SPc reduced droplet contact angles while increasing cyproflanilide uptake and residue retention in oilseed rape. Bioassays showed that SPc loading reduced the 72 h LC50 values by 5.5-fold against green peach aphids and 3.9-fold against fall armyworms. Transcriptomic analysis suggested that SPc-loaded cyproflanilide altered aphid gene expression associated with defense responses, transport, detoxification, cuticle formation, and juvenile hormone regulation. These findings highlight SPc-based nanodelivery as a promising strategy for enhancing pesticide efficacy and advancing sustainable pest management.