Calling behaviour and male response towards sex pheromone of poplar moth <Emphasis Type="Italic">Condylorrhiza vestigialis</Emphasis> (Lepidoptera: Crambidae)

The calling behaviour of virgin females Condylorrhiza vestigialis Guenée, 1854 (Lepidoptera: Crambidae) and the female pheromone gland extract activity were studied under laboratory conditions. Most of the females started calling from their first scotophase period after emergence. Maximum calling occurred between the seventh and tenth hours of the scotophase period. The length of the calling increased with age until the fourth scotophase, but the onset of calling time did not differ with age. The number of calling bouts increased significantly with age, but the mean duration of each calling bout (20.8 min) did not vary with age. Extracts of pheromone glands evaluated in a Y-tube olfactometer attracted significantly more males than control, 70 and 30%, respectively. Gas chromatographic–electroantennogram detection (GC–EAD) analysis of these extracts indicated the presence of a single EAD-active peak, the putative sex pheromone of the species. This pheromone compound may be suitable for monitoring populations densities of C. vestigialis, and for detection of the onset of the seasonal flight period. An efficient pheromone is of importance also with respect to current attempts to develop new control methods for this important pest of Populus spp. in Brazil.