Disease Note

First Report of Bean Yellow Mosaic Virus on Dry Edible Beans in North Dakota. B. Odhiambo, Department of Plant Pathology, North Dakota State University, Fargo 58105. J. R. Venette, Department of Plant Pathology, North Dakota State University, Fargo 58105. Plant Dis. 69:542. Accepted for publication 7 March 1985. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-542f.

Two widely grown pinto bean (Phaseolus vulgaris L.) cultivars, Olathe and Pindak, showed mosaic virus symptoms 1 mo after planting in North Dakota variety trials during 1981 and 1983. These cultivars are resistant to the type and NY 15 strains of bean common mosaic virus (BCMV). The causal agent was sap-transmissible to the BCMV-resistant bean cultivars Amanda and Widusa and was not transmitted through seed. The pathogen induced systemic infection in white and yellow sweet clovers and in gladiolus. Infective sap had a dilution end point of 10^–3–10^–4 and a thermal inactivation point at 50–55 C and was noninfectious after aging 3–4 days. Virus particles (flexuous rods about 657 nm long) reacted strongly with bean yellow mosaic virus (BYMV) but not BCMV antisera in ELISA. We concluded the pathogen is a strain of BYMV, possibly from weed clovers.