Influence of Temperature and Helicoverpa armigera Food on Survival and Development of the Parasitoid, Campoletis chlorideae

Climate change is likely to affect the insect host and the activity and abundance of biological control agents. Therefore, the present studies were conducted to understand the influence of temperature and source of insect host, Helicoverpa armigera on survival and development of the ichneumonid parasitoid, Campoletis chlorideae. Temperatures <12°C and >35°C were detrimental to the survival and development of the larvae of C. chlorideae. Post-embryonic development period of C. chlorideae was significantly and negatively associated with increase in temperature. The parasitoid required more numbers of degree days to complete development at lower temperatures, and took about 2.5-fold more time to complete development at 18°C than at 27°C. The parasitoid development was prolonged by six days under ambient conditions (average 23°C; range 12 to 25°C) than at a constant temperature of 27°C, indicating that fluctuations in temperature have a significant influence on parasitoid development. The males and females were heavier when reared at 18 and 27°C than when reared under ambient conditions. Percentage parasitization and adult emergence were influenced by host insect food, and parasitoid strain × temperature. The results indicated that changes in temperature as a result of climate change would have considerable influence on survival and development of C. chlorideae. This information would be useful for understanding the influence of climate change on the activity and abundance of natural enemies, which in turn would have great bearing on insect-pest population dynamics, insect damage and crop production.