Temperature-mediated functional responses of Neoseiulus womersleyi and N. longispinosus (Acari: Phytoseiidae) to Tetranychus urticae (Acari: Tetranychidae)

Abstract: The effect of temperature on the functional response of Neoseiulus womersleyi and N. longispinosus to eggs of the spider mite Tetranychus urticae was examined. Logistic regression indicated that both N. womersleyi and N. longispinosus exhibited a type II functional response on eggs of the prey. The attack rate coefficient (a) of N. womersleyi increased with temperature increasing from 15 to 30 °C and declined at 35 °C, whereas that of N. longispinosus peaked at 20 °C. At 30 and 35 °C the attack rate was higher in N. womersleyi than in N. longispinosus. The handling time (Th) of both species declined exponentially with temperature increasing from 15 to 35 °C. At all temperatures the handling time of N. longispinosus was shorter than that of N. womersleyi. The efficiency of conversing ingested food into egg biomass (ECI) was affected by temperature and prey density. The temperature-mediated ECI model indicated that the coefficient differed between the two species at 30 and 35 °C. The implications for the interaction of temperature, prey and predator should be considered for suitable biological control strategies against spider mites.