Incidence of Tomato Ringspot Virus and Tobacco Ringspot Virus in Grapevines in Pennsylvania. C. A. Powell, Pennsylvania Department of Agriculture, Harrisburg 17110. J. L. Longenecker, and L. B. Forer. Pennsylvania Department of Agriculture, Harrisburg 17110. Plant Dis. 74:702-704. Accepted for publication 2 February 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0702.

In southeastern Pennsylvania, tomato ringspot virus (TmRSV) and tobacco ringspot virus (TbRSV) were detected by ELISA both individually and together in declining Cascade grapevines and in symptomless vines adjacent to infected ones but not in other symptomless vines in one vineyard. In a survey of randomly selected grapevines (Vitis spp.) from 12 other vineyards in southeastern Pennsylvania, TmRSV and TbRSV were detected in one and 11 of 60 Seyval and one and two of 35 Chancellor vines, respectively. Forty Chelois grapevines were ELISA-negative for both viruses. In Erie County (the major grape-producing region of the state, located in northwestern Pennsylvania), grapevine varieties Niagara, Chelois, Aurora, and Concord exhibiting a variety of viruslike symptoms were also ELISA-negative for TmRSV and TbRSV. However, two declining Seyval and one declining Cascade grapevines were infected with TbRSV, and two declining Cascade grapevines were infected with TmRSV. Several declining vines of both cultivars were ELISA-negative.