Partial characterisation of a novel Tobamovirus infecting Actinidia chinensis and A. deliciosa (Actinidiaceae) from China

Actinidia chinensis and A. deliciosa plants from China, showing a range of symptoms, including vein clearing, interveinal mottling, mosaics and chlorotic ring spots, were found to contain ~300 nm rod-shaped virus particles. The virus was mechanically transmitted to several herbaceous indicators causing systemic infections in Nicotiana benthamiana, N. clevelandii, and N. occidentalis, and local lesions in Chenopodium quinoa. Systemically- infected leaves reacted with a Tobacco mosaic virus polyclonal antibody in indirect ELISA. PCR using generic and specific Tobamovirus primers produced a 1,526 bp sequence spanning the coat protein (CP), movement protein (MP), and partial RNA replicase genes which showed a maximum nucleotide identity (88%) with Turnip vein clearing virus and Penstemon ringspot virus. However, when the CP sequence alone was considered the highest CP sequence identity (96% nt and 98% aa) was to Ribgrass mosaic virus strain Kons 1105. The morphological, transmission, serological and molecular properties indicate that the virus is a member of subgroup 3 of the genus Tobamovirus.