Study on mathematical model for temperature–dependent development of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinelidae)

The mealybug destroyer, Cryptoleamus montrouzieri Mulsant is known as the most effective biological control agent of the mealybugs. The effect of temperature on developmental rate of C. montrouzieri was studied. Developmental times of incubation period, larval, pupal, and overall immature stages of the mealybug destroyer were recoreded at temperatures ranging 15–35°C, 50–60% RH, and a photoperiod of (L:D) 16:8h. According to the ANOVA, temperature affected significantly developmental time of the mealybug destroyer at 1% of probability level and increasing temperature lead to decreasing developmental time. In order to describe temperature–dependent development and to estmate related thermal indices, developmental rate of C. montrouzieri modeled as a function of temperature using mathematical models. The results showed Briere–2 and Lactin non–linear models had the best performance to predict developmental rate of C. montrouzieri in the studied temperature range. According to the non–linear models, thermal tolerance for development of the overall immature stages of the mealybug destroyer was 10.40–33.56°C and optimal temperature was 30.08°C. Obtained results can be used for improving environmental conditions of the mealybug destroyer mass rearing instectariums and biological control programs.