CHARACTERIZATION OF AN ISOLATE OF PEPPER MILD MOTTLE TOBAMOVIRUS OCCURRING IN CANADA

A tobamovirus was isolated from tobacco mosaic virus (TMV)-resistant H ungarian cultivars of sweet pepper (Capsicum annuum) in commercial pep per production fields at Richmond, BC, and shown to be a strain of pep per mild mottle virus (PMMV) on the basis of experimental host range, serology, morphology, and cDNA-RNA hybridization. The type strain of P MMV and the very similar Samsun latent strain of TMV (SLV) appeared to be more similar to each other genomically than to the Canadian isolat e. Several tobamoviruses were isolated from buffer-washes of seed furn ished by growers in Richmond and Oliver, BC, but PMMV was isolated onl y from Richmond samples, suggesting that the occurrence of the disease in Canada was a consequence of planting infected or contaminated seed .