Cellulose bait improves the effectiveness of Metarhizium anisopliae as a microbial control of termites (Isoptera: Rhinotermitidae)

The efficacy of a new virulent Metarhizium anisopliae strain (SRRC 2558) obtained from Coptotermes formosanus in China was evaluated against the eastern subterranean termite, Reticulitermes flavipes and the Formosan subterranean termite, C. formosanus, in the laboratory. This new strain was compared with three other virulent M. anisopliae strains and was found to be highly infectious against termites. It caused 100% mortality to groups of 100 R. flavipes workers in containers with treated vermiculite/sand medium at a concentration of greater-or-equal, slanted3 × 106 conidia/cm3. However, in two-container choice devices, R. flavipes avoided containers treated with M. anisopliae at the concentration of greater-or-equal, slanted1.5 × 107 conidia/cm3. Cellulose powder bait containing M. anisopliae was tested against R. flavipes and C. formosanus. At effective concentration, the bait did not cause apparent repellence to R. flavipes and C. formosanus. Successful control of R. flavipes and C. formosanus groups (1000/group) was achieved at 1.5 × 108 and 3 × 108 conidia/g, respectively, in choice tests in which termites were provided with treated cellulose bait and untreated wood.