甘蓝夜蛾Mamestra brassicae Linnaeus飞行能力研究

【目的】测定日龄、性别、交配等因素对农业迁飞性害虫甘蓝夜蛾Mamestra brassicae Linnaeus飞行能力的影响,为其迁飞行为研究和异地测报提供理论依据。【方法】在气温为(24±1)℃、相对湿度为75%±5%的实验室环境下,利用飞行磨系统对甘蓝夜蛾实验室种群1~5日龄未交配个体、已交配的3日龄个体以及野外迁飞种群分别进行连续24 h吊飞测试,记录其累计飞行时间、累计飞行距离、平均飞行速率等参数。【结果】甘蓝夜蛾实验室种群的飞行能力随日龄增长而变化,初羽化时即具有较强的飞行能力,2~3日龄达到峰值,4~5日龄的飞行能力显著下降;雌性甘蓝夜蛾的飞行能力强于雄性甘蓝夜蛾;交配的甘蓝夜蛾平均飞行速率显著小于处女甘蓝夜蛾,但二者的平均飞行时间和飞行距离均无显著差异。此外,渤海湾迁飞种群中晚季节南迁种群的飞行能力显著强于早季节北迁种群和过渡种群。【结论】日龄和交配状态是影响甘蓝夜蛾飞行能力的关键因素。

Preliminary study of the flight capacity of the cabbage moth,Mamestra brassicae Linnaeus

Objectives] To test the effects of age, sex and mating etc. on the flight capacity of the cabbage moth, Mamestra brassicae Linnaeus (Lepidoptera: Noctuidae), an important migratory insect pest of vegetable crops throughout the world. Methods] The flight performances of mated and virgin male and female M. brassicae were examined by tethering individuals to computerized flight mills for 24 h to measure the parameters of total flight distance, flight time, and flight velocity, under a laboratory conditions at a temperature of (24±1)℃ and relative humidity of 75%±5%. Results] Mean flight velocity, duration, and distance, varied with age. The flight capacity of M. brassicae was strong after emergence, peaked at 2- to 3-days of age, and then underwent a significant decrease in 4- to 5-day old moths. The flight capacity of the females was greater than that of males. The mean flight velocity of mated moths was significantly less than that of virgin moths, but there were no significant difference in mean flight duration and flight distance between mated and virgin moths. The flight capacity of the southward migratory population was significantly higher than that of the northward migratory population and that of the transitional population collected in the Bohai Gulf. Conclusion] Age and mating status are the key factors affecting the flight capacity of M. brassicae.