Effect of Short-Term High-Temperature Stimuli on the Functional Response of Trichopria drosophilae (Matsumura)

SIMPLE SUMMARY: Soft fruit is an economically important global fruit crop. Drosophila suzukii is a significant pest of soft fruit, including grape bayberry. In China, Trichopria drosophilae is the dominant pupal parasitoid of D. suzukii. In order to control the population of D. suzukii more effectively and reduce the use of pesticides, researchers have investigated the potential role of T. drosophilae in the biological control of D. suzukii in China. In this paper, we investigated the functional response and control potential of T. drosophilae on D. suzukii pupae at different temperatures. Our aim was to expand the range of control applications for T. drosophilae. We investigated the functional response and interference effect of T. drosophilae and found that T. drosophilae showed good levels of parasitic ability on D. suzukii pupae in the laboratory environment. At temperatures of 23 °C to 35 °C, T. drosophilae exhibited a type II functional response on D. suzukii pupae. ABSTRACT: Researchers have previously investigated the role of Trichopria drosophilae as a pupal parasitoid in the biological control of Drosophila suzukii in China. Here, we investigated the ability of T. drosophilae to parasitize D. suzukii pupae at different temperatures. To do this, we evaluated the functional response of T. drosophilae to D. suzukii pupae at different temperatures and investigated the specific effects of density on parasitism. The results show that the parasitic functional response of T. drosophilae under different high-temperature stimuli is Holling type II. After processing at 29 °C, the instantaneous search rate was 1.1611; the theoretical maximum parasitic value was 20.88 at 31 °C. The parasitic efficiency decreased with increasing stimulation temperature, as the host pupa density increased from 5 to 25, and the strongest search effect occurred at 0.87 at 27 °C. The searching effect of T. drosophilae at each temperature fell gradually with an increase in prey density from 5 to 25. At 31 °C, the theoretical parasitic maximum of T. drosophilae reached a maximum of 20.88 pupae. At this temperature, when a pair of T. drosophilae was placed in a pupa density of 50, its actual total number of parasites was 18.60.