A simulation model for predicting the efficiency of biological control of spider mites by phytoseiid predators. 2. Validity tests and data necessary for practical usage

Abstract

Validity tests of the simulation model developed in the previous report (SAITO et al., 1996) using two sets of experiments under two different greenhouse conditions revealed that the model was able to precisely predict the dynamics of predator-prey interactions with minor changes in a few variables: On strawberry plants in a well regulated glasshouse, when the predator searching efficiency was decreased to 87% of the standard value and the ratio of prey female and predator female at which the predators begin to disperse was ca. 7: 1, the dynamics of predator-prey populations were well simulated. On cucumber plants in a vinyl-house under free-ranging temperature conditions, 30% decrease in searching efficiency and 20% decrease in sedentary rate were necessary to simulate the most fitting pattern of predator-prey dynamics. These changes in rate variables were thought to be reasonable considering the differences in features and sizes of the plants. Therefore, the present model appears to be useful in demonstrating the controlling process and predicting the result of biological control. Several environmental and biological factors which should be determined before biological control is implemented were also discussed.