Peanut Mottle Virus in Texas Snap Beans. M. J. Silbernagel, USDA-ARS, Washington State University, Prosser, WA 99350-9687. L. J. Mills, Washington State University, Prosser, WA 99350-9687. Plant Dis. 75:430. Accepted for publication 3 December 1990. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0430B.
Peanut mottle virus (PMV) caused systemic necrosis of leaves, petioles, stems, and pods of snap bean (Phaseolus vulgaris L.) in west Texas during 1987. Host range, symptomatology, electron microscopy, and serology of the Texas snap bean isolate (PMV-TS) were within the parameters of PMV-M and PMV-N (1). Inoculations at bloom of the cultivar Del Monte 0441, from which PMV-TS was isolated, reproduced the disease observed in the field. This is the second report of PMV damage on beans in the United States; the first incidence was recorded in 1983 in New York (2) in a bean field near peanut (Arachis hypogaea L.). Because the virus is seedborne in peanuts (1), aphid transmission from peanuts to beans was the presumed source of inoculum. Use of resistant cultivars (2) and isolation of bean crops from peanut fields should control the disease. Symptoms induced by PMV on some bean cultivars may be confused with systemic necrosis caused by strains of bean common mosaic virus (BCMV). Systemic necrosis of stems and pods caused by BCMV is pronounced in vascular bundles, whereas necrosis caused by PMV is superficial.