Isolation of Three Viroids and a Circular RNA from Grapevines

Abstract

SUMMARYAnalysis of nucleic acids from grapevine tissues by two-dimensional gel electrophoresis demonstrated the presence of two bands of circular RNA. The smaller RNA contained about 300 nucleotide residues and was identified as hop stunt viroid by nucleotide sequencing. The larger RNA band was a mixture of species and contained similar amounts of two components, referred to as RNA la and RNA lb, and in addition a trace amount of citrus exocortis viroid (CEV) which became detectable only after inoculation of the mixture to tomato. The identity of CEV was determined by probe hybridization and nucleotide sequencing. Both RNAs la and lb are distinct from CEV and have estimated sizes larger than those of CEV and other viroids reported so far. RNA la preparations were infectious in cucumber and in tomato and the recovered viroid had unique properties. We have provisionally named this viroid Australian grapevine viroid. Evidence for the autonomous replication of RNA lb was not obtained.

Hop Stunt Viroid Strains from Dapple Fruit Disease of Plum and Peach in Japan

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Citrus exocortis viroid and Hop Stunt viroid Doubly infecting grapevines in Brazil

“…Despite the stunting and yellowing symptoms that HSVd induces in cucumber, no disease symptoms are observed in grapevines infected by this viroid. CEVd was also isolated from symptomless grapevines in Spain, Australia and California (García-Arenal et al, 1987;Rezaian et al, 1988;Semancik and Szychowski, 1992).…”