In vitro cultivation of the entomopathogenic fungus Entomophthora thripidum: isolation, growth requirements, and sporulation

Entomophthora thripidum Samson, Ramakers & Oswald (Zygomycota, Entomophthor ales) was isolated fi-om Thrips tabaci Lindeman (Thysanoptera, Thripidae; o nion or potato thrips). Vegetative fungal cells were released into culture medium by opening surface sterilized insects and multiplied in Grace's inse ct tissue culture medium supplemented with yeastolate, lactalbumin hydrolys ate and 10% fetal bovine serum (FBS). These cells grew as protoplasts (no s taining for cell wall) and aggregated to form pellets that were only observ ed in vitro. After exhaustion of the medium, walled mycelium formed which p roduced forcibly ejected spores when transferred onto water agar.