Abstract
Cucumber plants (Cucumis sativus) with necrotic spots, yellowing and mosaic symptoms were found in Kochi Prefecture, Japan in 1995. The causal agent was identified as Melon yellow spot virus (MYSV) on the basis of host reactions, stability in crude sap, particle morphology, transmission by Thrips palmi, serological relationships and the identity of amino acid sequence of the N protein. This is the first report of the occurrence of MYSV on cucumber, and the name “potted wilt”s was proposed for the disease.
