1 Soil and Water Science Department, Genetics Institute, University of Florida-IFAS, Gainesville, Florida, USA.
2 Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine, California, USA.
3 Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California, USA.