CO_2 anesthesia enhances infection rate of Cordyceps militaris (Hypocreales: Clavicipitaceae) on pupae of the silkworm, Bombyx mori

摘要

An entomogenous fungus, Cordyceps militaris, grows on larvae and pupae of the silkworm, Bombyx mori. To overcome problems in the establishment of fungal infection caused by advancing pupal-adult development, we tested the effects of carbon dioxide (C02) anesthesia. Pupae inoculated with C. militaris were held in C02 anesthesia for 2 days. Almost all pupae exposed to COa were infected withひmilitaris, but the rate of infection of chilled or untreated pupae decreased with increasing stage of pupal-adult development at inoculation. The results indicate that exposure of silkworm pupae to C02 enhances infection rate. This treatment will support the mass production of C. militaris for pharmacological uses.