SOUTHERN BLIGHT, CAUSED BY ATHELIA ROLFSII, IS A SIGNIFICANT YIELD LIMITING PATHOGEN IN WARMPRODUCTION AREAS CIRCUMGLOBALLY. THE OVERARCHING GOAL OF THIS PROJECT IS TO IMPROVE SOUTHERNBLIGHT MANAGEMENT IN ANNUAL CROPS BY DEVELOPING A RISK FORECASTING TOOL THAT CAN BE USED BYGROWERS TO OPTIMIZE INTEGRATED MANAGEMENT STRATEGIES. THIS WILL BE ACHIEVED BY 1) DETERMININGGROWTH THRESHOLDS FOR A. ROLFSII IN A LABORATORY SETTING, 2) DEVELOPING A MODEL TO PREDICT THE RISKOF SOUTHERN BLIGHT IN TOMATO AND POTATO, 3) AND IMPLEMENTATION OF THE MODEL FOR INTEGRATEDMANAGEMENT OF SOUTHERN BLIGHT IN ANNUAL ROTATIONS. THIS WORK WILL BE ACCOMPLISHED THROUGHLABORATORY, COMPUTATIONAL, AND FIELD-BASED RESEARCH IN COLLABORATION WITH GROWERS AND FARMADVISORS IN THE SACRAMENTO AND CENTRAL VALLEYS. THE PRIMARY AFRI PRIORITY AREA ADDRESSED BYIMPROVING SOUTHERN BLIGHT MANAGEMENT IN ANNUAL CROPPING SYSTEMS IS PLANT HEALTH PRODUCTIONAND PRODUCTS. ADDITIONALLY, THE PROJECT IS RELEVANT TO AGRICULTURE SYSTEMS AND TECHNOLOGY THROUGHTHE DEVELOPMENT OF A MOBILE APPLICATION AND WEB PLATFORM TO ASSIST FARMERS WITH THEMANAGEMENT DECISION MAKING. FURTHERMORE, PROJECT OBJECTIVES WILL IMPACT AGRICULTURE ECONOMICSAND ENVIRONMENTAL ASPECTS OF AFRI PRIORITY AREAS THROUGH COST MATRICES OF MANAGEMENT PRACTICESAND OPTIMIZED SPRAYS BASED ON DISEASE RISKS. IN ORDER TO BETTER PREDICT THE ONSET OF SOUTHERNBLIGHT AND TO IMPROVE MANAGEMENT, WE PROPOSE TO DEVELOP A MODEL, BASED ON FUNGAL BIOLOGY ANDWEATHER CONDITIONS, TO PREDICT SOUTHERN BLIGHT RISK. ADDITIONALLY, WE PLAN TO ASSESS DISEASEAMELIORATION AND COST EFFECTIVENESS WHEN INTEGRATING STRATEGIC CROP ROTATIONS WITH MODEL-BASEDFUNGICIDE REGIMENS.