Three Serotypes of Prunus Necrotic Ringspot Virus Isolated from Rugose Mosaic-Diseased Sweet Cherry Trees in Washington. G. I. Mink, Plant Pathologist, Department of Plant Pathology, Irrigated Agriculture Research and Extension Center, Washington State University, Prosser 99350. W. E. Howell, Anabel Cole, and S. Regev. Research Technologist, Former Research Associates, Department of Plant Pathology, Irrigated Agriculture Research and Extension Center, Washington State University, Prosser 99350, Washington State University, College of Agriculture and Home Economics, Pullman 99164. Plant Dis. 71:91-93. Accepted for publication 9 July 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0091.

Three distinct serotypes of Prunus necrotic ringspot virus (NRSV) (designated CH-3, CH-9, and CH-30) were isolated from sweet cherry trees in Washington that showed similar symptoms of cherry rugose mosaic disease. Among more than 50 NRSV isolates serotyped, only one isolate of serotype CH-30 and two isolates of serotype CH-3 were found. Two of these isolates were from trees in Washington known to have been infected before 1970; the other was from Canada. Most NRSV isolates obtained from sweet cherry trees in Washington, almond and cherry trees in California, and pollen from beehives brought to Washington from California were serotype CH-9. This serotype also included isolates A, E, G, and H described earlier in Wisconsin. Serotype CH-9 isolates were transmitted from trees showing a range of symptoms.