The optimum temperature-humidity combination for the feeding activities of Japanese subterranean termites

Two species of Japanese subterranean termite, Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe), were used in an investigation of the optimum temperature-relative humidity (RH) combination for their feeding activities. Daily wood consumption per worker and survivals were measured, and the protozoan fauna in the hindgut were observed under 15 temperature-RH combinations for 1 week. Five temperatures (20degrees, 25degrees, 30degrees, 35degrees, and 40degreesC) and three RH conditions (50%, 70% and 90% RH) were examined. The activities of the workers were highest at around 30degreesC for both species, and workers died at 40degreesC within 5 days and 2 days for C. formosanus and R. speratus, respectively. The optimum RH condition for feeding activity was 90% RH for C. formosanus and 70%-90% RH for R. speratus. The optimum temperature-RH combinations for feeding activities were 30degreesC at 90% RH for C. formosanus and 30degreesC at 70%-90% RH for R. Speratits.