The Potential of Four Dry Bean Cultivars to Serve as Sources of Pseudomonas phaseolicola Inoculum. M. J. Katherman, Department of Plant Pathology, Cornell University, Ithaca, NY 14853. R. E. Wilkinson, and S. V. Beer, Department of Plant Pathology, Cornell University, Ithaca, NY 14853. Plant Dis. 64:72-74. Accepted for publication 7 March 1979. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-72.

Seedlings of the cultivars California Light Red Kidney, Redkloud, Redkote, and HLR (a breeding line with a high degree of halo blight resistance) were inoculated with Pseudomonas phaseolicola and transplanted into small plots containing healthy snap bean plants to assess the ability of inoculated plants to serve as sources of inoculum in the field. The percentage of transplants around which snap bean plants showed symptoms of halo blight was 80% for the cultivar California Light Red Kidney and 40% for the cultivar Redkloud. No significant difference was found among the number of secondary infection centers that developed in plots with Redkote and HLR transplants and in control plots without transplants. There was a direct relationship between a cultivar’s susceptibility to halo blight and its potential to serve as an inoculum source after artificial inoculation.