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Develop laboratory systems to determine the bacterial profile (quantity and types of bacteria present in manure, soil, plant, or air) as affected by management system, environment, and time. Isolate bacteriophages for Campylobacter, Salmonella spp., and Yersinia as indicators of bacterial presence and use in control of pathogens. Determine soil chemical properties which impact fate of harmful manure pathogens.
Approach: Develop mechanical system for repeatedly photographing and measuring, over time, the same plated colony on inoculated plates using a rotating stage and position tracking with computer program. Using different culture media and dilutions and spiral inoculated plates, microbial profile changes are determined of gram-negative enteric bacteria as a function of management systems applied in CRIS 6406-12630-003-00D. Samples of swine lagoon effluent and poultry litter are tested for presence of bacteriophages using bacterial 'lawns' of American Type Culutre Collecting in a double-agar-layer plaque assay. Phage is diluted to characterize individual isolates using electron microscopy and standard techniques. Spiked samples and natural manure samples are applied to four well-characterized soils in percolation column studies and in runoff studies. Microbial profiles are determined in water samples collected with simulated rain events as a function of time, temperature, soil characters, and, where appropriate, soil depth.