Effect of temperature on the management of shoot borer through entomopathogenic nematodes

Studies on the effect of temperatures on the pathogenicity of EPNs, Heterorhabditis sp., Steinemema spp. and Oscheius spp. belonging to Steinernematidae, Heterorhabditidae and Rhabditidae group against shoot borer (Conogethes punctiferalis) larvae and their production was also tested. The rate of mortality of larvae and production of EPNs varied among the test group and within temperature regimes. Among the test temperature, maximum mortality of shoot borer larvae by Steinernematidae and Heterorhabditidae (100%) followed by Rhabditidae (91%) group was found at 28°C, whereas the least mortality of larva was recorded at 20°C. Maximum number of infective juveniles (IJs) was produced at 30°C followed by 28°C, whereas minimum production was recorded at 25°C. No production of IJs of the Steinernematidae, Heterorhabditidae and Rhabditidae group was recorded at 20 and 35°C. The study indicated that temperature of 25–30°C is optimum for mortality of shoot borer larvae and production of EPNs.