Estimating development and temperature thresholds of Ephestia kuehniella: toward improving a mass production system

The development of the Mediterranean flour moth, Ephestia kuehniella (Zeller), was evaluated at 10, 15, 17.5, 20, 22.5, 25, 27.5, 30 and 32.5°C with no lighting. None successfully completed development at 10 and 32.5°C. The total development time from egg to adult emergence was 164, 140, 98, 76, 61, 62 and 50 days, respectively, at the remaining temperatures. The developmental rate of E. kuehniella was described by the common linear model and six non-linear models. The lower temperature threshold for the immature stages and the thermal constant for E. kuehniella were 9°C and 1111 degree-days (DD) to complete development from egg to newly emerged adult. Non-linear models estimated the lower and upper thermal thresholds (Tmin and Tmax) and optimal temperature (Topt). The values of Tmax calculated by three nonlinear models ranged from 34°C to 46°C; Topt for each stage of development varied from 24 and 31°C, consistent with the temperature (30°C) at which the most rapid development occurred. Information on the threshold temperatures for development and thermal requirements can be utilized to predict E. kuehniella population dynamics and phenology and to evaluate optimal temperature conditions for mass rearing in stored products.