An Innovative Method for Sex Determination of the European Spruce Bark Beetle Ips typographus (Coleoptera: Scolytinae)
Bednarz, Bartłomiej; Kacprzyk, Magdalena
The sex of Ips typographus Linnaeus 1758 caught in trap trees was determined using an innovative weight measurement-based method. Statistically significant differences in the fresh and dry weight between males and females of I typographus were shown. The Eight toothed Spruce bark beetle females were 42 % heavier than males. Similarly, significant differences in the weight of insects and their absolute volume were detected, in favor of females. Aclear disparity in the parameters of weight and differences in male and female volume weighted index after maturation feeding demonstrates the possibility of using the criterion of weight for relatively simple sex determination. This method forms the basis for studies on the sex structure of bark beetles caught in pheromone traps in Norway spruce stands affected by cambiophages outbreaks in Poland.
Ips typographus (Linnaeus 1758) • Picea abies (Linnaeus 1753) Karsten 1881 • Eighttoothed spruce bark beetle • insect dry weight • insect fresh weight • insect volume weighted index • sex ratio • trap trees