Investigations on the flight behaviour of Anisandrus dispar (FABRICIUS, 1792) (Coleoptera: Scolytidae) in trap catches in apple orchards of the Lower Adige Valley in South Tyrol.

Abstract

Anisandrus dispar (Fabricius, 1792), known as "ambrosia beetle" is a pest of economic concern. To characterize its seasonal flight activity, we monitored populations from 2018 to 2024 by using ethanol-baited traps in two distinct phenological areas within the apple growing region of lower Adige Valley, Italy. Two independent trapping sites were positioned in each area. During all years and in all locations, we observed a main period from February to the end of May, where the A. dispar female flight occurred. However, the initiation of flight activity differed significantly between "early" and "late" phenological areas. The analysis of the six years of flight dynamics period provides some new insights. These findings improve our current understanding of its flight activity and provide a hypothesis related to more accurate prediction of the start of the female flight in spring.