Response of Early- and Late-Planted Soybeans to Natural Infection by Bean Pod Mottle Virus. J. P. Ross, Research Plant Pathologist, ARS, USDA, and Professor (retired), Department of Plant Pathology, North Carolina State University, Raleigh 27695-7616. Plant Dis. 70:222-224. Accepted for publication 26 September 1985. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1986. DOI: 10.1094/PD-70-222.

A field experiment was conducted in 1983 to measure the effect of bean pod mottle virus (BPMV) infection on yields of three cultivars of soybean (Glycine max) planted on 29 June. Plants were subjected to the following treatments: 1) mechanical inoculation with BPMV on 22 July, 2) natural inoculation by transmission of BPMV by bean leaf beetles, or 3) covering with window-screen cages to exclude the vector until 2 August. Yield losses of treatments 1 and 2 compared with 3 for cultivars Centennial, Davis, and Forrest were 19.2 and 15.8, 13.9 and 2.3, and 17.4 and 11.2%, respectively. Severity of symptoms and estimations of percentage of plants infected on 3 August appeared related to yield reductions. Transmission of BPMV occurred in 0.013% of seed harvested from beetle-inoculated Centennial and Forrest. In 1984, Forrest was planted on 2 May, and plots were either covered with screen cages to exclude the vector for 1 mo or exposed to beetle feeding (virus transmission). Plots in the latter treatment yielded 16.7% less than those of caged plants. Results indicate that beetle-transmitted BPMV can significantly reduce soybean yields in both early- and late-planted soybeans.