ABSTRACT
Infected plants may have double-stranded-(ds)-RNAs when a) the infecting viral genome is ds-RNA, as in phytoreoviruses and cryptoviruses, or b) ds-RNA is produced as a replicating form during the process of replication of single-stranded (ss)-RNA viruses. In the case of certain viruses, such as velvet tobacco mottle virus, ds-RNA may accumulate during replication. This technique of detecting the ds-RNA is useful for the early and rapid recognition of virus infection. The presence of ds-RNA can be detected by either polyacrylamide gel electrophoresis (PAGE) or antiserum reaction with ds-RNA. The quantity of ds-RNA obtained may vary with host-virus combinations (Valverde et aI., 1986). The ds-RNA may be isolated and labeled or cloned as cDNA for developing nucleic acid probes.
