Relationships between the cryptic and temperate viruses of alfalfa, beet and white clover.

Small isometric virus particles containing double-stranded RNA have been independently reported in Europe and Japan from apparently healthy alfalfa (Medicago sativa), beet (Beta vulgaris), and white clover (Trifolium repens). They have been called cryptic viruses in Europe and temperate viruses in Japan. Serological comparison using immunoelectron microscopy, and polyacrylamide gel electrophoresis of the RNAs indicate that alfalfa cryptic and temperate viruses are the same, beet cryptic virus is probably a mixture of two different viruses, one of which is similar to or the same as beet temperate virus, and white clover temperate virus is a mixture of at least three different viruses, two of them indistinguishable from white clover cryptic viruses 1 and 2, respectively, and the third very likely the same as white clover cryptic virus 3.