A simulation model for predicting the efficiency of biological control of spider mites by phytoseiid predators. 1. The model

Abstract

We developed a computer simulation model predicting the efficiency of Phytoseiulus persimilis ATHLAS-HENRIOT as a biological control agent of Tetranychus urticae KOCH. This model consisted of two main sets of 17 state variables, one for the predator and the other for the prey. The changes of these variables were calculated by difference equations using various rate variables which had appeared in the reports of many authors. Two particular components in the present model were a dispersal (or cannibalism) rate of the predator depending upon female prey density and a coefficient which decreases predation rate depending upon the features of the plant. These were thought to be important to predict actual state of biological control by computer simulation and should be evaluated by experimental and simulation studies in the future.