Performances of the cotton bollworm,Heliothis armigera (Hubner) at different temperatures and relative humidities

The cotton bollworm, Heliothis armigera (Hubner) is an important insect species at-tacking many crops. Their performances have been examined at temperatures from 15℃ to 35℃ and relative humidities (RH) between 22.5% and 100%, respectively, in order to assess possible effect of climate in future on its occurrence and infestation. Durations of all developmental stages of the insect shortened with increasing temperature. The temperature favoring population growth ranged from 25℃ to 30℃.Larval duration and adult longevity decreased as relative humidity increased, but development of other stages was independent of RH. At RH of over 64%, their survival rate, egg production and oviposition rate varied a little, and all the population parameters of the insect remained at a relative constant level.