A simple model for describing the effect of temperature on insect developmental rate

The linear and Logan models are usually used to describe the effect of temperature on insect developmental rate. The linear model is often used to estimate the lower developmental threshold. However, it cannot be used to calculate the upper developmental threshold. Additionally, it fails to describe developmental rates near, at, and above the optimal developmental temperature. The Logan model can reflect temperature-dependent developmental rates from the lower to upper developmental thresholds. It is often used to compute the optimal developmental temperature and the upper developmental threshold, but it is not used to compute the lower developmental threshold. To avoid the disadvantages of these two models, we develop a new model, the 'performance model' on the basis of the impact of increasing temperature on enzyme activity and denaturation. The performance model was first used by Huey and Stevenson (Amer. Zool. 19, 357-366) to provide a statistical description of the impact of body temperature on performance, but they did not provide underlying physiological mechanisms. Few studies have used the performance model to analyze the temperature-dependent developmental rates of insects, perhaps because of the lack of a theoretical justification. Here, we provide a theoretical justification to use the model and we use the performance model to evaluate the developmental rate data of two insect species. We found that the performance model has advantages over the linear and Logan models, and that the lower and upper developmental thresholds can be simultaneously obtained from this model. (C) Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2010. Published by Elsevier B.V. All rights reserved.