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In this research, functional responses of Amblyseius swirskii Athias-Henriot preying on different Tetranychus urticae Koch nymphal densities (2, 4, 8, 16, 32, 64, and 128) were studied at eight constant temperatures (15, 20, 25, 27.5, 30, 32.5, 35 and 37.5°C) in a circular Petri dish (3-cm diameter × 1-cm height) under lab conditions. At all temperatures, the logistic regression showed a type II functional response. A nonlinear relationship was found between temperature and attack rate and the reciprocal of handling time. The reciprocal of handling time decreased exponentially with increasing temperature. In contrast, the attack rate grew rapidly with increasing temperatures up to an optimum, showing a decreasing trend at higher temperatures. In order to quantify the functional response of A. swirskii over a broad range of temperatures and to gain a better estimation of attack rate and handling time, a temperature-settled functional response equation was suited to our data. Our model showed that the number of prey consumed increased with rising prey density. Also, the predation rates increased with increasing temperatures but decreased at extremely high temperatures. Based on our model, the predation rate begins at the lower temperature threshold (11.73°C) and reaches its peak at upper temperature threshold (29.43°C). The coefficient of determination (R2) of the random predator model was 0.99 for all temperatures. The capability of A. swirskii to search and consume T. urticae over a wide range of temperatures makes it a good agent for natural control of T. urticae in greenhouses.

In this study, we examined the fecundity, survival, and adult longevity of Ephestia kuehniella (Zeller) at different temperatures (15, 17.5, 20, 22.5, 25, 27.5, and 30 °C), and developed a model of oviposition. The fecundity, survival, and adult longevity of E. kuehniella were affected by temperature. Longevity reduced from 15.7 d at 15 °C to 8.79 d at 30 °C. Total fecundity was lowest (160.54 eggs) at 30 °C and highest (351.75 eggs) at 25 °C. The relationship between temperature and total fecundity was described by a nonlinear function. Cumulative age-specific egg laying fitted well to the two-parameter Weibull equation and survival of adults fitted well to a reverse logistic curve. These three temperature-dependent attributes (age-specific cumulative egg laying, temperature-dependent total fecundity, and age-specific survival rate) were integrated into a model of oviposition. Simulation of oviposition using the model has the potential to be useful for predicting patterns of occurrence of E. kuehniella egg populations in stores.