The influence of temperature on life history traits of Diadegma mollipla (Hymenoptera: Ichneumonidae), an African parasitoid of the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)

The use of Diadegma mollipla (Holmgren) as a biocontrol agent for diamondback moth (DBM)—a notorious pest of crucifers—can potentially be improved with increased scientific knowledge of the D. mollipla’ s life history. This study investigated the influence of temperature on the life history traits of D. mollipla parasitizing DBM under laboratory conditions with 20 female D. mollipla for each of five constant temperatures i.e., 15, 20, 25, 30 and 35 °C. Data analysis using curvilinear regression models showed that D. mollipla’ s highest intrinsic and finite rates of population increase, net reproductive rate, survival of immatures, daily fertility, shortest immature development and doubling times were achieved between 26 and 30 °C. Thus the results of this study provide evidence to that D. mollipla does not thrive well outside the 26–30 °C temperature range. These results provide baseline information for guiding the use of D. mollipla in the biological control of the destructive DBM pest.