Influence of temperature on the rate of development of Helicoverpa armigera (Hubner) (Lepidoptera : Noctuidae)

We investigated the effects of a range of constant temperatures (13.3-32.5 degreesC) on the development of all stages of Helicoverpa armigera (Kumamot o population) reared on tomato. The duration of the different life history stages decreased as temperature increased from 13.3 degreesC to 32.5 degree sC. A developmental threshold of 10.5 degreesC, 11.3 degreesC and 13.8 degr eesC was estimated for the eggs, larvae and pupal stages, respectively. A t hermal constant of 51 degree-days above a threshold of 10.5 degreesC was re quired for the development of the eggs. The larval stage required 215.1 deg ree-days and the pupal stage 151.8 degree-days above 11.3 degreesC and 13.8 degreesC developmental thresholds, respectively. Results from these studie s may provide information important for predicting the field population phe nology of H. armigera in Kumamoto Prefecture.