Importance of temperature for the performance and biocontrol efficiency of the parasitoid Perilitus brevicollis (Hymenoptera: Braconidae) on Salix

• With the prospect of warmer temperatures as a consequence of ongoing climate change, it is important to investigate how such increases will affect parasitoids and their top-down suppression of herbivory in agroecosystems. Here we studied how the performance and biocontrol efficiency of the willow "bodyguard" Perilitus brevicollis Haliday (Hymenoptera: Braconidae) were affected at different constant temperatures (10, 15, 20, 25A degrees C) when parasitizing a pest insect, the blue willow beetle (Phratora vulgatissima L., Coleoptera: Chrysomelidae). Parasitism did not reduce herbivory at all at 10A degrees C, indicating poor biocontrol efficiency at low temperatures. At higher temperatures, however, parasitism reduced herbivory substantially, implying that biocontrol may be promoted by a warmer climate. Parasitoid performance (survival and development rate) generally increased with increasing temperature up to 20A degrees C. The only exception was body size, which followed the temperature-size rule and decreased with increasing temperature. Our results indicate that a warmer climate may enhance the biocontrol of the blue willow beetle in environments that currently are cooler than the parasitoid's optimal temperature for development.

Subject headings

NATURVETENSKAP  -- Biologi -- Ekologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Ecology (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)