豆野螟成虫行为学特征及性信息素产生与释放节律

Adult behavior and circadian rhythm of sex pheromone production and release of the legume pod borer,Maruca vitrata (Fabricius) (Lepidoptera:Pyralidae)

豆野螟Maruca vitrata（Fabricius）是一种严重的泛热带豆类蔬菜害虫。本文在（29±1）℃、相对湿度75％-80％、光周期14L：10D条件下研究了豆野螟成虫的羽化、交尾行为以及雌蛾性信息素的释放节律。结果表明：其羽化行为全天可见，在雌蛾中，86％于暗期羽化；在雄蛾中，73％于暗期羽化。雌雄蛾羽化行为在暗期第4、5和8h差异达到显著（t〉4；P〈0．05）。交尾活动发生在暗期19：00到5：00之间，交尾持续时间最短约为20min，最长约为90min，3日龄进入暗期第5h具有最高的交尾率。1、6和7日龄成虫具有单个交尾高峰，2到5日龄成虫具有两个交尾高峰。同一日龄成虫交尾在暗期前半段平均花费的时间要明显高于在后半段花费的时间。低龄和高龄的成虫用于交尾的时间明显高于中龄的性成熟成虫。成虫的开始交尾时间随着日龄的增加逐渐前移。雄蛾对进入暗期后第5h和第9h处女雌蛾的性腺提取物和空气收集性信息素的触角电位反应最强，对3日龄处女雌蛾的性腺提取物和空气收集性信息素的触角电位反应最强。处女雌蛾田间诱蛾试验表明：23：00—01：00为诱蛾高峰期，3日龄处女雌蛾的诱蛾效果最好。该蛾的羽化、交尾及性信息素产生与释放均存在节律上的一致性。雌蛾的性信息素释放的时间较长，见于整个暗期，然而交尾行为发生时间较短，主要发生于两个交尾高峰之间。

The legume pod borer, Maruca vitrata （Fabricius）, is a serious pantropical insect pest of grain legumes. Adult behavior and circadian rhythm of sex pheromone production and release of the legume pod borer were investigated at （29 ± 1）℃ and 75% -80% RH under 14L： 10D. The results showed that the emergence activity of M. vitrata occurred throughout the day, and 86% of females and 73 % of males emerged during the scotophase. The differences of emergence behavior between both sexes were statistically significant during the 4th, 5th and 8th hour of the scotophase （t 〉 4; P 〈 0.05）. The mating behavior took place from 19：00 to 05： 00. The mating duration varied from 20 to 90 min. The highest mating frequency occurred during the 5th hour of the scotophase for 3-day-old moths. Single mating peaks were observed for 1-, 6- and 7-day-old moths, while double mating peaks were observed for 2- to 5-day-old moths. Adults of the same age spent longer time in mating during the first half of the scotophase than during the second half of the scotophase. The mating behaviour of the moth was age-dependent. Young and old pairs spent more time in mating than mature pairs of the middle age. Advanced onset of time and peak for mating were observed directly by older moths. The EAG response of male moths was highest to the crude extract of pheromonal glands and air collection from 3-day-old virgin female moths and during the 5th and 9th hour of the scotophase. In the field tests, the highest percentage of the male moths was trapped during 23： 00- 01： 00, and more male moths were trapped by 3-day-old virgin female moths than by female moths of other age. The emergence activity, mating activity and the female sex pheromone release were synchronized at different ages and time of the scotophase. The sex pheromone release was almost constant throughout the scotophase, but mating behavior concentrated between the two mating peaks.