Viruses Infecting Six Species of Perennial Clover (Trifolium spp.) in Field Evaluations of Plant Introductions and Cultivars. R. Alconero, USDA, ARS, Northeast Regional Plant Introduction Station, Geneva, NY 14456. Plant Dis. 67:1270-1271. Accepted for publication 2 June 1983. 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, 1983. DOI: 10.1094/PD-67-1270.

Enzyme-linked immunosorbent assay (ELISA) was used to detect bean yellow mosaic virus (BYMV), clover yellow vein virus (CYVV), white clover mosaic virus (WCMV), and red clover vein mosaic virus (RCVMV) in 1-yr-old plants established in the field for germ plasm evaluations and in feral clover plants growing adjacent to cold frames and evaluation fields. Severe virus infections were observed in accessions of Trifolium hybridum, T. pratense, and T. repens that coincided with a higher proportion of multiple infections found in these species. T. ambiguum and T. medium were less affected and fewer multiple infections were detected. T. alpestre was intermediate in its response to virus infections in the field. All four viruses were detected in T. pratense and three (CYVV, WCMV, and RCVMV) in feral T. repens plants growing adjacent to cold frames and evaluation fields.