关键词: 大螟, 求偶行为, 交配行为, 性信息素, 交配干扰

Abstract: 【Aim】 Through the laboratory study on the calling and mating behaviors of the pink stem borer, Sesamia inferens, in a high-dose sex pheromone environment, the differences in inhibiting the calling and mating of S. inferens adults between the sex pheromone compounds cis-11-hexadecenal (Z11-16∶Ald) and cis-11-hexadecenyl acetate (Z11-16∶Ac) were analyzed and compared, to provide technical parameters for effective mating disruption technology of S. inferens in the field.【Methods】 In the wind tunnel, a high-dose sex pheromone environment was simulated, and the moving distance, calling and mating rates of female and male adults, as well as sex pheromone titers of female adults of S. inferens were measured through a combination of 2-D behavioral recording and analysis, behavioral observation and ovarian dissection, as well as extraction and GC-MS analysis of sex pheromone. The efficacy of mating disruption by synthetic sex pheromone was evaluated in the field by using active pheromone aerosol dispensers.【Results】 The moving distance of the male adults of S. inferens in the 1st hour of scotophase was longer than that in the other time periods. The moving distance of the male adults of S. inferens in the Z11-16∶Ac environment accounted for 51.8%±9.3% of the moving distance during the entire scotophase, and was much longer than that in the control (no sex pheromone released) and Z11-16∶Ald environments, however, no significant difference was found in the moving distance of female adults among different time periods of scotophase. The proportions of ovipositor extrusion of female adults in the Z11-16∶Ac and Z11-16∶Ald environments were significantly lower than that in the control environment. In the control environment, the proportion of ovipositor extrusion of the 1-day-old female adults was 76.7%±14.6%, which was significantly higher than those in the Z11-16∶Ald and Z11-16∶Ac environments ［(29.2%±13.1%) and (26.7%±11.7%), respectively］. However, there was no significant difference in the time and duration of ovipositor extrusion of female adults at different day-old in various mating disrupted environments. In the control environment, the mating rate of female and male adults was 72.2%±5.6%, but that in the Z1116∶Ac environment was 40.5%±3.4%, and that in the Z11-16∶Ald environment was only 45.2%±3.1%, suggesting that the mating rate in the control group was significantly higher than those in the mating disruption groups. In different mating disrupted environments, there was no significant difference in the pheromone titers of Z11-16∶Ald and 16∶Ac in female adults. Significant reduced sex pheromone titers of Z11-16∶OH and Z11-16∶Ac were found in the treatment by Z11-16∶Ac. The sex pheromone titers of Z11-16∶OH and Z11-16∶Ac in female adults in the control environment were (3.79±2.56) and (7.29±4.49) ng, respectively, and reduced to only (0.80±0.59) and (1.99±0.45) ng in the Z11-16∶Ac environment, respectively. The pheromone titers of Z11-16∶OH and Z11--16∶Ac in the Z11-16∶Ald environment showed no significant difference from those in the control environment. Field experiments verified the efficacy of mating disruption. Z11-16∶Ac exhibited more stable and efficient efficacy of mating disruption than Z11-16∶Ald, and the efficacy of mating disruption of Z11-16∶Ald might be related to geographical populations. 【Conclusion】 Z11-16∶Ac is required for the stable and efficient mating disruption of S. inferens adults. It is not enough to rely only on Z11-16∶Ald for mating disruption because its efficacy is associated with geographical populations. Z11-16∶Ac not only interrupts with the calling of male adults, but also affects the sex pheromone titer of female adults and the mating of female and male adults, therefore, it can improve the control efficacy in many aspects.

Key words: Sesamia inferens, calling behavior, mating behavior, sex pheromone, mating disruption