Plant-Mediated RNAi of Non-ATPase Regulatory Subunit Confers Soybean Resistance Against Bean Bug, Riptortus pedestris.

Abstract

Riptortus pedestris, is a major pest threatening soybeans and cause the soybean staygreen syndrome, which has recently become a significant and widespread issue in soybean production. Currently, chemical control remains the primary method for managing R. pedestris in the field, but it contributes to environmental pollution and increases the resistance risk. Plant-mediated RNA interference (RNAi) offers a target-specific and eco-friendly alternative for pest control. While RNAi has been shown to effectively control certain Coleoptera, its effects on piercing-sucking insects, such as R. pedestris, remain poorly understood. In this study, we characterized a non-ATPase regulatory subunit 6 (RPN6) from R. pedestris and demonstrated that downregulation of RPN6 expression significantly increased mortality and reduced oviposition. Phylogenetic analysis revealed that while RPN6 is highly conserved across Hemiptera, the double-stranded RNA (dsRNA) targeting RPN6 is species-specific. We subsequently developed dsRPN6-transgenic soybean lines, and feeding bioassays revealed these transgenic soybean lines exhibited high resistance to R. pedestris, with significantly reduced survival and oviposition rates in the pest. Importantly, the transgenic soybeans displayed moderate staygreen symptoms following infestation by R. pedestris, demonstrating that plant-mediated RNAi targeting of RPN6 confers effective resistance against R. pedestris, providing a promising strategy for bean bug management in agricultural practices.