Progress and Opportunities of In Planta and Topical RNAi for the Biotechnological Control of Agricultural Pests

In planta RNAi or host-induced gene silencing (HIGS) has undergone significant advancements that have rendered it efficient and stable at the transgenerational level in plants for regulating host genes and targeting genes of insect pests and plant pathogens. Similarly, topical RNAi or spray-induced gene silencing (SIGS) has garnered considerable attention as an environmentally sustainable, selective, and alternative approach to chemical control of insect pests and plant pathogens. Several biotechnology companies and startups have focused their efforts on RNAi-based solutions for topical application in agriculture. Nevertheless, further technological advancements are required to enhance the efficacy of topical RNAi in agriculture, including improved dsRNA delivery systems, better target gene selection, and addressing biosafety regulatory issues. Herein, this review discusses key advances and bottlenecks in RNAi, and summarizes successful applications of these RNAi-based technologies in agriculture focusing on in planta and topical RNAi to control insect pests and plant pathogens. Furthermore, this review delves into the patenting landscape, biosafety considerations, risk evaluations, and the current regulatory status of RNAi in Latin America. Finally, it explores the contributions of RNAi to plant science, food production, and fostering a more sustainable form of agriculture.