Laboratory of Sericultural Sciences, Faculty of Agriculture, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113 (JAPAN).
Baculoviruses are invertebrate-specifie pathogens and are infectious only to arthropods, with the vast majority of permissive species falling within one order Lepidoptera. Their invertebrate specificity offers a clear advantage towards the development of specific environmentally compatible insecticides. But, varying degrees of immunity against these viruses in most of the host insects are limiting their advantages as microbial pesticides. However, recent studies revealed some important immune systems against these viruses, such as protectlve function of peritrophic membrane of the gut, phenoloxidase pathway in the haemolymph and other resistances to the virus. But still, many lacunae exist and need further in-depth studies to be carried out to understand the phenomenon of insect immunity against the baculoviruses. This contributions,therefore, reviews the selected topics on the virus infection and replication and defensive system of the host insects against these viral pathogens.
