** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** FIRE BLIGHT, CAUSED BY THE BACTERIUM ERWINIA AMYLOVORA, IS A DEVASTATING DISEASE OF APPLE AND PEAR. IT NOT ONLY REDUCES YIELD BUT ALSO KILLS TREES THEREFORE IS A MAJOR CONCERN TO APPLE AND PEAR GROWERS. BLOSSOM PROTECT, A BIOLOGICAL CONTROL COMPRISED OF THE YEAST AUREOBASIDIUM PULLULANS, IS THE MOST EFFECTIVE BIOCONTROL MATERIAL OF FIRE BLIGHT. ORGANICALLY APPROVED, INTEGRATED DISEASE MANAGEMENT PROGRAM CENTERED AROUND BLOSSOM PROTECT HAS BEEN DEVELOPED AND SUCCESSFULLY USED IN THE PACIFIC NORTHWEST. HOWEVER, BLOSSOM PROTECT CAN CAUSE FRUIT RUSSETING, A DISORDER OF THE CUTICLE OF DEVELOPING FRUITLETS THAT COMPROMISES QUALITY, ESPECIALLY IN HUMID CLIMATES. CONSEQUENTLY, IN THE MORE HUMID EASTERN U.S., THE RISK OF FRUIT RUSSETING FROM BLOSSOM PROTECT HAS SLOWED DEVELOPMENT OF EFFECTIVE ORGANIC MANAGEMENT OF FIRE BLIGHT.THEREFORE, THIS RISK IS A CRITICAL BARRIER FOR ORGANIC TRANSITION WITHIN THE REGION, AND DEVELOPMENT OF METHODS THAT MAINTAIN FRUIT QUALITY BY MITIGATING RUSSETING RISK FROM BLOSSOM PROTECT IS AN IMPORTANT RESEARCH PRIORITY.IN THIS PROJECT, WE AIM TO TEST THREE RUSSETING MANAGEMENT STRATEGIES: 1. THE PROTECTION AND CLEARING STRATEGY TO REMOVE A. PULLULANS AFTER PROTECTION IS FINISHED, 2. THE REMEDY STRATEGY TO IMPROVE FRUIT FINISH USING PLANT GROWTH REGULATORS / MICRONUTRIENTS, AND 3. THE ADJUST STRATEGY TO FINE TUNE THE TIMING / DOSAGE OF BLOSSOM PROTECT.ULTIMATELY, WE AIM TO DEVELOP AN INTEGRATED PROGRAM THAT MAXIMIZE BOTH THE FIRE BLIGHT SUPPRESSION AND RUSSETING MITIGATION. OUR EXTENSION ACTIVITIES INCLUDE DISSEMINATING KNOWLEDGE ON RUSSETING MITIGATION TO THE ORGANIC TREE FRUIT COMMUNITY AND PROMOTING ORGANIC PRACTICES IN EASTERN U.S.