Attempt to Identify Sex Hormones in the Bodies of Selected Norway Spruce Bark Beetles

A gas chromatography technique was applied to the adults of Ips typograhus (L.) and Pityogenes chalcographus (L.) collected from pheromone traps placed in Norway spruce stands in southern Poland in distinguished population swarming periods for the qualitative and quantitative determination of steroid compound differences between insect sexes. Ten not yet identified for bark beetle compounds from the group of sterols, including cholestenone, 4,6-cholestadiene-3-one, choles-4-en-3,6-dione and 17β-Hydroxyandrosta-1,4-dien-3-one benzoate, which can potentially act as gender hormones were detected. The presence of ecdysone and 20-hydroxyecdysone in the bodies of the studied bark beetles was confirmed. However, slight differences in the content of ecdysteroids in the bodies of males and females may be only the remains of the insect’s metamorphosis. Due to the small differences in the extracted compounds between the females and males, their variability in concentrations during the swarming period seems to be useless as a basis for sex determination.