ABSTRACT
The utilization of tissue culture to investigate physiological processes began with the investigation of imaginal discs by Frew (1928). However, the interest in insect tissue culture heightened after 1960s when Grace’s medium came into existence in 1962 and the first insect cell line was established. This medium was suitable for culture of Lepidopteran tissues. Between 1970-1980 a number of investigations of biosynthesis in vitro of the primary constituents of cuticle, i.e. chitin and protein were established (Oberlander 1980). Thus over 100 cell lines have been establised so far from various insect tissues of several orders of insects, for example, Lepidoptera, Diptera, Homoptera, Hemiptera, Orthoptera, etc. (Lee and Hou 1992) and such cultures are generally considered as useful models for some fundamental studies in cell physiology, genetics and biochemistry, and for the study of insect pathogens and parasites. In fact, cell culture methods and their use in virus research has received a tremendous boost as reviewed recently in detail (Granados and Mckenna 1995) and the effects of insecticidal Bacillus thuringiensis (Bt) δ-endotoxin in insect cell line in vitro are well known (Knowles and Farndale 1988).
