ABSTRACT
Cauliflower mosaic virus (CaMV), the type member, has been studied more extensively than any of the other members and hence most of the discussion will be about this virus. Caulimovirus particles appear roughly spherical in negatively stained preparations, with little visible structural detail. The reported diameter of the particles ranges from about 42 to 50 nm depending on the staining method used. CaMV DNA has short discontinuities or gaps at well-defined sites on both strands of the circular double-stranded molecules. The primary DNA structures of the three CaMV strains which have been sequenced differ from one another by only about 5%. The differences are mainly due to base substitutions but there are also several deletions and insertions. Although the viroplasms of all Caulimoviruses are essentially similar, some minor differences have been noted among distinct strains of CaMV. The cytopathological effects of a number of CaMV strains infecting turnip plants have been compared directly.
