Electrophoretic Analysis of Double-Stranded RNA in Stocks of Cultivated Mushroom (Agaricus brunnescens). K. L. Deahl, Research Plant Pathologist, Vegetable Laboratory, Horticultural Science Institute, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705. J. P. San Antonio, and E. L. Civerolo. Plant Physiologist, Vegetable Laboratory, and Research Plant Physiologist, Fruit Laboratory, Horticultural Science Institute, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705. Plant Dis. 71:430-433. Accepted for publication 7 November 1986. 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, 1987. DOI: 10.1094/PD-71-0430.

Because an earlier detailed comparison by electron microscopy indicated that the detection of double-stranded RNA (dsRNA) by polyacrylamide gel electrophoresis (PAGE) was a very reliable diagnostic technique for virus infection in mushrooms, we initiated a study to determine if the PAGE method could be used to detect dsRNA in stock strains used to generate commercial spawns (seed). Sporophores were derived directly from test spawns by covering the spawn with a layer of casing material. Sporophores were grown in environmentally controlled isolation chambers. Based on an extensive evaluation analysis of spawns from eight separate national and international stock programs, 41% of the strains tested contained dsRNA. None of the isolates showed aberrant growth, but several strains had abnormal growth rates. Although fruiting initiation by several of the strains was difficult, there was no correlation between fruiting ability and dsRNA content.

Keyword(s): fungal virus, mushroom disease.