Some properties of clover blotch virus.

Clover blotch virus (CBV) was purified by differential centrifugation or precipitation with polyethylene glycol 6000 or 20000. Analytical centrifugation of purified CBV preparations revealed 2 components, the proportions of the lighter (96 S) nad heavier (112 S) being 88 and 12%, respectively. RNA isolated from purified CBV represented a micture of several RNA species of different molecular weight and its infectivity was by about 2 log units lower than that of the original nucleoprotein. CBV virions are isometric with a diameter of 28 nm. CBV is tentatively included into the Cucumovirus group.