Adult behaviors and sex attraction of Obolodiplosis rohiniae

Key Words：Obolodiplosis rohiniae, emergence, mating, sex pheromone

Abstract：         Observations on the periodicity of adult eclosion, mating, oviposition and sexual attraction of the black locust gall midge Obolodiplosis rohiniae (Haldemann) were conducted. The results indicate that peak female eclosion occurred between 05:00-06:00 and peak male eclosion occurred between 01:00-02:00 Peak male eclosion was earlier about 4 hours than that of female adults. Twenty minutes after emergence, female adults extended their ovipositors and attracted males for mating. Mating occurred mostly in 1dayold moths and was not observed in 2 to 3dayold moths. The peak of mating occurred between 05:00 and 06:00, and between 07:00 and 08:00 The peak of oviposition occurred between 20:00 and 22:00 An experiment using a“ Y”tube olfactometer indicated that both airborne chemicals collected from virgin females and those extracted by solvents can attract males; there was no difference in the attractiveness of the chemicals obtained by these two methods. Neither virgin males nor extracts from virgin males attracted females. The two alternative methods for collecting sex pheromones from virgin females are described. A trap baited with a virgin female attracted and captured males from as far as 80 to 300 cm under laboratory conditions. Mated females retained some attractiveness to males. The emergence, mating and release of sex pheromone of the gall midge exhibited diel periodicity