Selection of Optimal Physical Conditions for Mass Propagation of Catolaccus grandis (Hymenoptera: Pteromalidae) Aided by Regression

Abstract

Effects of temperature, relative humidity, and photoperiod on developmental time, reproductive potential, and rate of increase of Catolaccus grandis (Burks) were evaluated under laboratory conditions. Polynomial multiple regression models were used to estimate optimal levels of the 3 physical factors studied to maximize the reproductive potential and rate of increase of C. grandis . Net reproductive rate (Ro) was used as a measure of reproductive potential, and its maximum value occurred at 27°C, 63% RH, and a photoperiod of 16:8 (L:D) h. Maximum value of the intrinsic rate of increase (rm) of C. grandis occurred at 29°C, 66% RH, and 16:8 (L:D) h. Shortest developmental time within the physical factor levels studied was estimated to occur at 30°C, 67% RH, and 16:8 (L:D) h. Fecundity of C. grandis is maximized at 26°C, 68% RH, and a photoperiod of 16:8 (L:D) h according to regression model estimates.