Bacterization of Potatoes with Pseudomonas putida and Its Influence on Postharvest Soft Rot Diseases. P. D. Colyer, Former Research Assistant, Department of Plant Pathology, University of Massachusetts, Amherst 01003. M. S. Mount, Professor, Department of Plant Pathology, University of Massachusetts, Amherst 01003. Plant Dis. 68:703-706. Accepted for publication 20 February 1984. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-703.

Preplant treatments of potato seed pieces (cultivar Superior) and postharvest treatments of potato tubers with a Pseudomonas putida isolate antagonistic to Erwinia spp. were evaluated for their effect on soft rot development. The percent weight loss due to soft rot, the surface area and volume of tubers with rot, and the number of toothpick wounds from which rot developed were reduced by 50% in preplant treatments and by 75% in postharvest treatments. Greater soft rot reduction in postharvest treatments may have been the result of greater colonization of the tubers by P. putida.