FOODBORNE PATHOGENS SUCH AS SALMONELLA, LISTERIA, AND E. COLI O157:H7 FREQUENTLY CAUSE HUMAN ILLNESSES AND OUTBREAKS LINKED TO CONTAMINATED FRESH PRODUCE. FRESH PRODUCE SAFETY IS A HIGH PRIORITY FOR FOOD SAFETY AND PUBLIC HEALTH. DUE TO THE LACK OF EFFECTIVE INTERVENTION STRATEGIES FOR PATHOGEN REDUCTION, CURRENT PRODUCE INDUSTRY RELIES MAINLY ON CHLORINATED WATER WASHES FOR SURFACE DECONTAMINATION FOR FRUITS AND VEGETABLES. POWER ULTRASOUND IS A GREEN TECHNOLOGY AND HAS DEMONSTRATED A GREAT POTENTIAL IN ENHANCING PATHOGEN REDUCTION AT LABORATORY-SCALES. IN THIS STUDY, WE WILL EVALUATE THE EFFECTIVENESS OF PLANT-SCALE POWER ULTRASOUND TECHNOLOGY FOR PATHOGEN REDUCTION DURING FRESH PRODUCE WASHING, AND PROVIDE SCIENTIFIC BASIS FOR COMMERCIAL IMPLEMENTATION OF THIS GREEN TECHNOLOGY IN INDUSTRIAL WASHING AND SANITATION PRACTICE. TREATMENTS AND CONDITIONS DURING FRESH PRODUCE POST-HARVEST PROCESSING CAN TRIGGER A NUMBER OF ADAPTATION AND STRESS RESISTANCE MECHANISMS IN PATHOGENIC BACTERIA, ALLOWING SMALL POPULATIONS OF PATHOGENS TO SURVIVE AND SUBSEQUENTLY CAUSE CROSS CONTAMINATION IN THE WASHED PRODUCTS. USING ADVANCED RNA SEQUENCING TECHNOLOGY, WE WILL INVESTIGATE THE EFFECTIVENESS AND UNDERLYING MOLECULAR MECHANISMS OF CHLORINATED WATER WASHES, COUPLED WITH POWER ULTRASOUND AS A HURDLE TECHNOLOGY, IN REDUCTION OF BACTERIAL PATHOGENS ON WASHED PRODUCE SURFACE. A FUNDAMENTAL UNDERSTANDING OF THE STRESS RESISTANCE AND SURVIVAL MECHANISMS OF FOODBORNE PATHOGENS ON PRODUCE SURFACE AS WELL AS IN PERSISTENT RESERVOIRS WILL PROVIDE CRITICAL DATA FOR OPTIMIZING TREATMENT CONDITIONS AND DEVELOPING MODELS FOR RISK ASSESSMENT. COLLECTIVELY, THIS PROJECT WILL DELIVER HIGHLY NOVEL AND PRACTICAL SOLUTIONS TO IMPROVE THE SAFETY OF FRESH PRODUCE.