Objective 1: Elucidate biological factors and molecular mechanisms that enhance or reduce fitness characteristics related to survival and growth of enteric pathogens in the produce production continuum. Sub-objective 1A-1I (Refer to uploaded Project Plan) Objective 2: Identify environmental factors that affect the persistence and transmission of enteric pathogens in the produce production environment for risk assessment. Sub-objective 2A-2H (Refer to uploaded Project Plan) Objective 3: Develop methods for the detection and subtyping of enteric bacterial and viral pathogens from produce production environments; to aid epidemiological investigations and to distinguish pathogenic from non-pathogenic strains. Sub-objective 3A-3E (Refer to uploaded Project Plan) Objective 4: Study the ecology of Shiga toxin-producing E. coli (STEC) bacteriophages and its association with bacterial hosts. Objective 5: Development of immuno-, bacteriophage-, and mass spectrometry-based methods for rapid detection of foodborne pathogens.