Title: | Mechanisms of premating isolation between Helicoverpa armigera (Hubner) and Helicoverpa assulta (Guenee) (Lepidoptera: Noctuidae) |
Author(s): | Ming QL; Yan YH; Wang CZ; |
Address: | "State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, PR China" |
DOI: | 10.1016/j.jinsphys.2006.11.007 |
ISSN/ISBN: | 0022-1910 (Print) 0022-1910 (Linking) |
Abstract: | "Helicoverpa armigera and Helicoverpa assulta are sympatric sibling species, and in the laboratory they can interbreed and produce viable offspring. To assess the contributions of temporal barriers and sexual barriers to premating isolation, we investigated both the temporal rhythms of calling behavior and pheromone titers of H. armigera and H. assulta females and the behavioral responses of males to conspecific and heterospecific calling females in a wind tunnel. Both H. armigera and H. assulta females called throughout the scotophase, and there was more calling during the second half of the scotophase than during the first half. Maximal pheromone titer and maximal calling activity in H. armigera synchronously occurred at the sixth hour into the scotophase, whereas, in H. assulta, the maximal pheromone titer occurred 2 h before the peak of calling. Pheromone blend ratios of the two species were opposite and, within each species, changes in the ratio within the scotophase and at different ages were relatively small. Males of both H. armigera and H. assulta responded strongly to their conspecific calling females in the wind tunnel and completed the whole courtship sequence. In contrast, they did not land and had no copulation attempts in response to heterospecific calling females. These results show that the two species do not have obvious temporal differences in calling behavior and pheromone production, and the specificity of sex pheromone blend emitted by females plays a key role in their premating isolation. In addition, we summarized the potential isolation mechanisms of H. armigera and H. assulta" |
Keywords: | "Analysis of Variance *Animal Communication Animals Female *Genetic Speciation Moths/genetics/*physiology Reproduction/physiology Sex Attractants/analysis Sexual Behavior, Animal/*physiology Species Specificity Time Factors;" |
Notes: | "MedlineMing, Qing-Lei Yan, Yun-Hua Wang, Chen-Zhu eng Comparative Study Research Support, Non-U.S. Gov't England 2007/01/24 J Insect Physiol. 2007 Feb; 53(2):170-8. doi: 10.1016/j.jinsphys.2006.11.007. Epub 2006 Dec 8" |