Infection of Cultured Silkworm Eggs with the Nuclear-Polyhedrosis Virus

• Published in: Japanese Journal of Applied Entomology and Zoology Vol. 10; no. 4; pp. 197 - 204
• Main Authors: KANDA, Toshio, KITAZAWA, Toshio, SUGIYAMA, Hachiro, TAKAMI, Takeo
• Format: Journal Article
• Language: Japanese
• Published: JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY 1966
• ISSN: 0021-4914; 1347-6068
• DOI: 10.1303/jjaez.10.197

Intact eggs of the silkworm, Bombyx mori L., which are covered with chorion are suffocated in culture media because of inhibited gas exchange through respiratory canals. When the chorion was taken off, naked eggs developed well in culture media. And, when cultured eggs were infected with the virus, polyhedron formation was confirmed to occur in nuclei of various kinds of their tissues, including those in which polyhedron formation has never been reported at the larval and pupal stages: serosa, yolk cell, amnion, epidermis, tracheal epithelium, ganglion, fore-gut, hind-gut, silk-gland, muscle, fat-body, gonad, blood cell and mid-gut. This is remarkable, because polyhedron formation has never or scarcely been known in intact silkworm eggs, and definite results have not been obtained even by injection of virus in them. Diapause eggs also developed in culture media, though the growth of embryos was delayed 3 to 4 days as compared with cultures of non-diapause eggs. In accordance with this delay of growth, polyhedron formation was retarded or suppressed in cultures of diapause eggs. Culture of naked silkworm eggs can be applied as a simple technique to virus infection experiments under aseptic conditions and of use for studies of many problems of virus infection.