RNA INTERFERENCE (RNAI) IS A SEQUENCE-SPECIFIC GENE SILENCING MECHANISM AND A PROMISING NOVEL MODE OF ACTION FOR BIOPESTICIDES. EXOGENOUS RNAI OVERCOMES THE TECHNICAL CHALLENGES AND PUBLIC CONCERNS ASSOCIATED WITH TRANSGENIC APPROACHES. IT IS A NEXT-GENERATION PEST MANAGEMENT TOOL FOR CONVENTIONAL AND CONTROLLED ENVIRONMENT AGRICULTURE (CEA) SYSTEMS, A FAST-GROWING SECTOR IN NORTH AMERICA THAT CAN STRENGTHEN OUR FOOD SECURITY. KNOWLEDGE OF THE RNAI MOLECULE'S PERSISTENCE IN THE CEA ENVIRONMENT IS CURRENTLY LIMITED. THE LIMITED STABILITY AND INEFFICIENT UPTAKE OF RNAI BIOPESTICIDES ARE MAJOR CHALLENGES FOR EXOGENOUS RNAI OR SPRAY-INDUCED GENE SILENCING (SIGS) TECHNOLOGY. DIFFERENT DELIVERY TECHNIQUES, INCLUDING CHITOSAN NANOPARTICLES (CNP), HAVE BEEN INVESTIGATED TO FORM MORE STABLE SPRAYABLE RNAI PRODUCTS. MODIFICATION OF THE DSRNA'S STRUCTURE IS ANOTHER PROMISING APPROACH THAT SHOWS POTENTIAL FOR FORMING MORE STABLE SPRAYABLE RNAI WITH ENHANCED CELLULAR UPTAKE. BEFORE IMPLEMENTING THIS APPROACH, IT IS CRUCIAL TO ASSESS THE ENVIRONMENTAL PERSISTENCE AND POTENTIAL UNINTENDED EFFECTS THAT MAY RESULT FROM INCORPORATING NANOPARTICLES ALONG WITH DSRNA STRUCTURE MODIFICATIONS. THE PROPOSED PROJECT WILL DETERMINE THE PERSISTENCE OF CNP-LINEAR VS. CNP-SECONDARY (HAIRPIN- AND PAPERCLIP-) STRUCTURE-DSRNA IN SOILS, SOIL-LESS SUBSTRATES, AND HYDROPONIC CROP PRODUCTION SYSTEMS.ADDITIONALLY, THE PROPOSAL AIMS TO EVALUATE WHETHER MODIFICATION OF THE DSRNA STRUCTURE, ALONG WITH ITS INCORPORATION INTO CNP, HAS DETRIMENTAL EFFECTS ON THE RHIZOSPHERE AND PHYLLOSPHERE MICROBIOTA AND BENEFICIAL MICROBES. THEREFORE, THIS PROPOSAL IS DIRECTLY RELEVANT TO THE PROGRAM AREA PRIORITY 5G. THE OUTCOMES OF THIS PROPOSED WORK WILL GENERATE CRITICAL INFORMATION FOR EVALUATING THE ENVIRONMENTAL PERSISTENCE AND ECOLOGICAL IMPACTS OF SECONDARY STRUCTURED RNAI MOLECULES THAT ARE DESIGNED TO BE MORE STABLE. IN ADDITION, THIS PROPOSED WORK WILL GENERATE ROBUST EVIDENCE ON THE DSRNA'S PERSISTENCE IN CEA SETTINGS.