A damaging outbreak of arabis mosaic nepovirus in black currant, the occurrence of other nepoviruses in Ribes species, and the demonstration that alfalfa mosaic virus is the cause of interveinal white mosaic in black currant

摘要

Chlorotic mottling and ringspot symptoms were observed on leaves in black currants cv. Baldwin, in the Irish Republic. Severe crop loss was associated with infection by arabis mosaic nepovirus (ArMV) and the presence in the soil of its nematode vector, Xiphinema diversicaudatum. This is only the second report of ArMV damaging a black currant crop. Tomato black ring (TBRV) and raspberry ringspot nepoviruses were detected in single plants of red currant in England and flowering currant (Ribes sanguineum) in Scotland, respectively; each of these infected plants showed foliar chlorotic line-pattern symptoms. This is the first record of TBRV in red currant. A single black currant plant in New Zealand showing symptoms typical of those described for interveinal white mosaic disease, contained alfalfa mosaic alfamovirus (AMV). When AMV particles were purified and concentrated from herbaceous tests plants and mechanically inoculated to young black currant plants, several became infected with AMV and mostinfected plants developed systemic symptoms typical of the original disease. It is concluded that this provides the strongest evidence to date that AMV is the causal agent of interveinal white mosaic disease.