Parasitism of cotton whitefly, Bemisia tabaci on cucumber by Eretmocerus mundus: Bionomics in relation to temperature

Selected life history characteristics of Eretmocerus mundus Mercet parasitizing the cotton whitefly, Bemisia tabaci (Gennadius) on cucumber were studied at four constant temperatures (20, 25, 30 and 32 °C). Egg to adult developmental time of female ranged from 23.57 days at 20 °C to 11.6 days at 32 °C. An average of 266 degree-days is required to complete development above the lower threshold temperature (8.1 °C). Preimaginal survivorship was 71, 98, 84.8 and 59.2% at 20, 25, 30 and 32 °C, respectively. Mean adult longevity of female E. mundus ranged from 10.5 days at 20 °C to 3.8 days at 32 °C. Mean total fecundity ranged from 68 to 173 eggs/female. The sex ratio (female %) ranged from 48 to 55%. Intrinsic rate of increase (rm) increased with temperature from 0.098 at 20 °C to 0.287 at 30 °C and then decreased to 0.230 at 32 °C. Generation time decreased from 23.9 to 11.5 days with increasing temperature. These data can be used to maximize the production of E. mundus from mass rearing facilities and to develop computer simulation models to predict E. mundus development and population dynamics for release programs.