Evaluation of Plant Introductions of Phaseolus spp. for Resistance to White Mold. J. E. Hunter, Department of Plant Pathology, New York State Agricultural Experiment Station, Cornell University, Geneva 14456. M. H. Dickson and M. A. Boettger, Department of Seed and Vegetable Sciences, and J. A. Cigna, Department of Plant Pathology, New York State Agricultural Experiment Station, Cornell University, Geneva 14456. Plant Dis. 66:320-322. Accepted for publication 22 June 1981. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-320.

Higher levels of resistance to white mold (Sclerotinia sclerotiorum) than previously known in Phaseolus vulgaris were detected under growth chamber conditions using a limited-term inoculation method. Fifty percent or higher survival occurred in only 13 of 310 lines from Europe, whereas 16 of 139 introductions with tolerance to root rot survived the white mold test. Most of these originated in Central or South America, although two lines from Turkey had a high level of resistance. A group of F₅ plants derived from P. vulgaris × P. coccineus crosses had a comparatively high survival ratio. The eight lines of P. coccineus subsp. polyanthus from Mexico that were tested all had a high level of resistance. A change in the limited-term inoculation method is described that makes it easier and faster to use for large-scale testing.

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