Abstract
Pathogenicity tests with two strains of Bombyx cytoplasmic-polyhedrosis virus, with polyhedra showing hexagonal and tetragonal outlines, to several lepidoperous insects were conducted. A Bombyx virus occluded in hexagonal polyhedron was transmitted to Scopelodes contracta, Dendrolimus spectabilis, Malacosoma neustria testacea, Lymantria dispar japonica, Lymantria mathura aurora, Clostera anastomosis orientalis, Spiralctia subcarnea, and Dictioploca Japonica. On the other hand, a Bombyx virus occluded in tetragonal polyhedron was transmitted to Scopelodes contracta, Dendrolimus spectabilis, Malacosoma neustria testacea, Lymantria dispar japonica, Lymantria mathura aurora, Clostera anastomosis orientalis, Arcte coerulea, Spilarctia subcarnea, and Philosamia cynthia pryeri. The Bombyx virus passed through the larvae of different insect species still retained its infectivity to the silkworm, Bombyx mori.
