Abstract
A disease of carrot plants showing yellowing of leaves and stunting of growth occurred in Hokkaido. Foliage symptoms consisted of chlorotic mosaic, yellowing and malformation of leaflets. The virus, spherical particle with 25 nm in diameter, infected the plants of 30 species from 10 families, and positively reacted with broad bean wilt virus (BBWV) antiserum. In thin sections of the diseased broad bean leaves, crystalline arrays of virus particles and amorphous vesicular body were observed in the cytoplasm. From these results, it is evident that the causal virus is BBWV. When carrot plants were infected with BBWV in the early stages of plant growth, the yield of root crops was reduced by about 30%.
