The pathogenic effects of Beauveria bassiana (Bals.) Vuill. (Deuteromycotina: Hyphomycetes) were evaluated against workers of the termite Odontotermes obesus (Rambur) (Isoptera: Termitidae) in the laboratory. Termite mortality ranged from 41–90% in treatments, compared with 19–21% in controls. Both lethality and lethal time varied significantly with conidial concentration and age of culture. Mycelial growth was recorded on the leg joint, abdomen, antenna, thorax and head regions of treated cadavers after 24 h. Also observed in treatments were body surface shrinkage, colour change, and hardened and brittle appendages. The role of B. bassiana in the control of O. obesus workers is discussed.
