USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648, USA.
Department of Plant Science, California State University, Fresno, 2415 East San Ramon Avenue, Fresno, CA 93740, USA.
J Insect Sci. 2022 Sep 1;22(5). doi: 10.1093/jisesa/ieac059.
Navel orangeworm, Amyelois transitella (Walker), is a key pest of walnuts, pistachio, and almonds in California. Pheromone mating disruption using timed aerosol dispensers is an increasingly common management technique. Dispenser efficiency may be increased by timing releases with the active mating period of navel orangeworm. Past work found that the peak time of sexual activity for navel orangeworm females is 2 h before sunrise when temperatures are above 18°C. Inference of male responsiveness from data collected in that study was limited by the necessity of using laboratory-reared females as a source of sex pheromone emission to attract males and the inherent limitations of human observers for nocturnal events. Here we used camera traps baited with artificial pheromone to observe male navel orangeworm mating response in the field over two field seasons. Male response to synthetic pheromone exhibited diel patterns broadly similar to females, i.e., they were active for a brief period of 2-3 h before dawn under summer conditions and began responding to pheromone earlier and over a longer period of time during spring and fall. But contrary to the previous findings with females, some males were captured at all hours of the day and night, and there was no evidence of short-term change of pheromone responsiveness in response to temperature. Environmental effects on the response of navel orangeworm males to an artificial pheromone source differ in important ways from the environmental effects on female release of sex pheromone.
脐淡黄卷蛾，Amyelois transitella (Walker)，是加利福尼亚州核桃、开心果和杏仁的主要害虫。利用定时气溶胶分配器进行信息素交配干扰是一种越来越常见的管理技术。通过与脐淡黄卷蛾的活跃交配期同步释放来提高分配器的效率。过去的研究发现，脐淡黄卷蛾雌虫的性活动高峰期是在日出前 2 小时，此时温度高于 18°C。由于必须使用实验室饲养的雌性作为性信息素释放源来吸引雄性，以及人类观察者对夜间事件的固有局限性，从该研究中收集的数据推断雄性的反应能力受到限制。在这里，我们使用带有人工信息素的摄像头陷阱在两个野外季节在野外观察雄性脐淡黄卷蛾的交配反应。雄性对合成信息素的反应表现出与雌性大致相似的昼夜节律模式，即在夏季条件下，它们在黎明前活跃 2-3 小时，而在春季和秋季，它们开始更早地对信息素做出反应，并持续更长的时间。但与之前对雌性的研究结果相反，有些雄性在白天和黑夜的任何时间都被捕获，并且没有证据表明它们对温度的信息素反应能力会发生短期变化。环境对雄性对人工信息素源的反应的影响与环境对雌性释放性信息素的影响在重要方面存在差异。
