An experimental and modelling study of the demographic performance of Rhyzopertha dominica (F.). I. Development rate

Experiments are described in which data on developmental rate of the lesser grain borer, Rhyzopertha dominica, were collected over a wide range of tem peratures (15-39 degrees C) and relative humidities (20-70%). The results d iffered from previously published work in that development was completed at temperatures as low as 18 degrees C, although only at relative humidities of 55% or above. Development was not completed at less than 30% r.h. at any temperature. In general, the rate of development observed in this study wa s lower than that in the literature. The data collected from these experime nts were used to develop submodels for emergence pattern and rate of develo pment. The derived model of development rate includes both exponential and logarithmic functions of temperature and humidity and does reflect well the critical observed interaction between temperature and relative humidity. T his study has important implications for the effective use of grain-cooling with ambient aeration to restrict insect population growth. (C) 1998 Elsev ier Science Ltd. All rights reserved.