Temperature-Dependent Developmental Models for Predicting the Phenology of Maladera matrida (Coleoptera: Scarabaeidae)

Maladera matrida Argaman is a key pest of peanuts (Arachis hypogaea L.) in Israel. The ability to predict accurately the occurrence of different developmental stages of this beetle may facilitate and improve the control of population of this pest. Thus, 4 non linear (logistic, exponential, sigmoid, and biophysical) models and 1 linear model were tested to fit the relationship between the developmental rate of M. matrida and temperature in a wide range of constant temperatures (20-31 ± 1°C). The required degree-days and the developmental threshold were estimated from the linear portion of the biophysical model, which provided the best fit to the developmental rate data generated in the laboratory. A linear phenological model using the parameters derived from the biophysical model accurately predicted the developmental time of the early generation of M. matrida in peanut fields but failed to predict developmental time of later generations. Predictive extension timing estimation (PETE), a time varying distribution delay model, accurately predicted the occurrence of both early and late generations. It is critical for growers to be able to predict the occurrence of 1st instars in the soil of germinating peanut fields following the emergence of the pest after overwintering. This information allows peanut growers to be prepared with monitoring and control devices to reduce the damage caused by M. matrida to peanuts.