THIS PROPOSAL FOR $271,036 ADDRESSES THE CRITICAL AGRICULTURAL RESEARCH AND EXTENSION (CARE) PROGRAM AREA PRIORITY AND ADDRESSES FARM BILL PRIORITY A. PLANT HEALTH AND PRODUCTION AND PLANT PRODUCTS. IN PARTICULAR, THE PROPOSED WORK ADDRESSES INSECTICIDE-RESISTANT SOYBEAN APHIDS THAT ARE A REGIONAL PROBLEM THAT HAS NATIONAL SIGNIFICANCE, DUE TO THE REGIONS CONTRIBUTION TO OVERALL SOYBEAN PRODUCTION.COST-EFFECTIVE MANAGEMENT OF SOYBEAN APHID RELIES ON THRESHOLD-BASED APPLICATIONS OF INSECTICIDES. HOWEVER, THE SOYBEAN APHID HAS RECENTLY EVOLVED RESISTANCE TO ONE OF THE MOST COMMONLY USED GROUPS OF INSECTICIDES (I.E., PYRETHROIDS). WITH FEW OTHER PEST MANAGEMENT TOOLS, THE MAGNITUDE AND MECHANISMS OF THIS RESISTANCE PROBLEM NEEDS TO BE ASSESSED AND RESEARCH-BASED RESISTANCE MANAGEMENT RECOMMENDATIONS DEVELOPED AND DISSEMINATED. WE PROPOSE TWO RESEARCH-FOCUSED OBJECTIVES TO: 1) DETERMINE THE GEOGRAPHIC AND TEMPORAL VARIABILITY SOYBEAN APHID RESISTANCE TO PYRETHROIDS; AND 2) DETERMINE GENETIC AND PHYSIOLOGICAL COMPONENTS RELATED TO PYRETHROID RESISTANCE IN SOYBEAN APHID. WE ALSO PROPOSE TWO COMPLEMENTARY EXTENSION FOCUSED OBJECTIVES TO: 3) CHARACTERIZE ATTITUDES OF SOYBEAN GROWERS TOWARD SOYBEAN APHID MANAGEMENT AND INSECTICIDE RESISTANCE; AND 4) DISSEMINATE THE RESULTS AND MANAGEMENT RECOMMENDATIONS DEVELOPED BY THIS PROJECT. THIS PROJECT HAS STRONG SUPPORT FROM AGRICULTURAL STAKEHOLDERS AND WILL BE GUIDED BY INPUT FROM AN ADVISORY BOARD COMPOSED OF MEMBERS FROM THESE GROUPS. OVERALL RESULTS OF THIS PROJECT WILL MITIGATE THE POTENTIAL ECONOMIC AND ENVIRONMENTAL COSTS ASSOCIATED WITH INSECTICIDE RESISTANCE IN THIS PEST.