Project Number: 8042-32420-006-11-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 1, 2014
End Date: Sep 30, 2018
The purposes of this project are: 1) To determine the duration of survival of fecal indicator bacteria (E. coli) and other enteric bacteria in manure-amended soils in the Northeast U.S. (Vermont), and 2) identify routes of Salmonella spp. and Listeria monocytogenes contamination on cantaloupes during growing and post-harvest transfer operations.
A research or small commercial farm using raw animal manure as fertilizer will be identified in Vermont. Populations of fecal indicator bacteria (FIB) or enteric bacteria will be determined at the outset of manure application and at regular intervals up to 270 days following application. If produce crops are planted during this time, transfer of FIB or enteric bacteria to the produce crop will be examined as well. This will occur at the same site over multiple seasons over the course of three years to determine if 270 days is an appropriate interval between the application of manure fertilizer and harvest of produce. Since 270 days is the ‘no harvest interval’ between manure application and harvest of produce crops, results will be directly pertinent to current rule-making by FDA. Separately, cantaloupes grown in Beltsville in naturally contaminated soils will be analyzed for Salmonella spp. populations to determine extent of pathogen transfer from soil to melon. Post-harvest operations (scrubbing, brushing, washing, air-cooling) will also be examined for their potential to introduce Listeria monocytogenes to uninoculated cantaloupes. These growing and post-harvest practices will attempt to experimentally mimic those practices thought to have occurred in recent cantaloupe outbreaks. Post-harvest operations of cantaloupes will then be evaluated for optimal mitigation strategies to reduce both Salmonella and L. monocytogenes contamination of cantaloupes.