Hypovirulence of chestnut blight fungus conferred by an infectious viral cDNA.

Printer-friendly versionPrinter-friendly versionPDF versionPDF version
TitleHypovirulence of chestnut blight fungus conferred by an infectious viral cDNA.
Publication TypeJournal Article
Year of Publication1992
AuthorsChoi, GH, Nuss, DL
Date Published1992 Aug 7
KeywordsDNA, Viral, Open Reading Frames, Phenotype, Plant Diseases, Restriction Mapping, RNA, Double-Stranded, RNA, Viral, Transformation, Genetic, Virulence, Xylariales

Strains of the chestnut blight fungus Cryphonectria parasitica that contain viral double-stranded RNAs often exhibit reduced virulence. Such hypovirulent strains act as biocontrol agents by virtue of their ability to convert virulent strains to hypovirulence after anastomosis. Transformation of virulent C. parasitica strains with a full-length complementary DNA copy of a hypovirulence-associated viral RNA conferred the complete hypovirulence phenotype. Cytoplasmic double-stranded RNA was resurrected from the chromosomally integrated complementary DNA copy and was able to convert compatible virulent strains to hypovirulence. These results establish viral double-stranded RNA as the casual agent of hypovirulence and demonstrate the feasibility of engineering hypovirulent fungal strains.

Alternate JournalScience
PubMed ID1496400