The Properties of Two Recent Isolates of Cytoplasmic Polyhedrosis Viruses

Abstract

Cytoplasmic polyhedrosis viruses (CPV) were isolated from laboratory cultures of Bombyx mori and Spodoptera exempta. The electrophoretic profile of the RNA segments of both viruses showed similarities with that of type 1 CPV. Whereas the virus isolate from B. mori appeared identical to type 1 CPV (as assessed by serology and comparative mobilities of RNA segments and structural polypeptides), the isolate from S. exempta was distinct. Three of the 10 viral RNA segments did not co-run with type 1 RNA, and the structural polypeptides of polyhedra had different MW. The S. exempta isolate should be included as a new type (type 12) in the classification of these viruses.