Characterization of four isolates of Bombyx mori nucleopolyhedrovirus

Bombyx mori nucleopolyhedroviruses (BmNPVs), isolated from a sericultural K orean farm, were purified and characterized by their DNA restriction patter n, virus replication, polyhedra production and gene structures. The EcoR I and Sal I fragments showed similar overall patterns with minor difference b ut distinguishable patterns in each isolate. There was no significant diffe rence in the virus replication pattern, yield of total polyhedra production and polyhedra morphology, but the yield of released polyhedra by BmNPV-K1 in Bm5 cells was 2 to 5 times higher than that of other isolates. In compar ative studies of p10 gene, BmNPV-K1 and K3 had same structure and they enco ded a protein consisting of 94 amino acids. Although BmNPV-K2 encoded the s ame length of amino acids with BmNPV-K1 and K3, it had different structure, and BmNPV-K4 had the p10 gene encoding 70 amino acids.