实验条件下黏虫、棉铃虫和小地老虎的定向行为比较

定向是昆虫迁飞过程中的一个重要行为,定向行为的微小差异将导致迁飞轨迹的巨大差异。为建立实验室测定夜间迁飞昆虫定向的方法,本文尝试了室内用自制的飞行模拟器测定诱捕到的正在迁飞的黏虫、棉铃虫和小地老虎的定向行为。结果表明这3种昆虫的单个个体都存在显著的定向行为,但只有黏虫存在共同定向行为。黏虫在模拟飞行过程中飞行时间最长并且能很快转向其偏爱的方向进行定向,用飞行模拟器可以很好地测定其定向(包括方向及持续时间),因此这种方法适于用来进一步研究黏虫的定向机制。而棉铃虫飞行时间较短,定向不稳定,小地老虎自由旋转时间较长,定向角度杂乱,是否适合用此飞行模拟器研究其定向行为及机制还有待进一步研究。

Comparative studies on orientation behaviors of Mythimna separata, Helicoverpa armigera, and Agrotis ypsilon in the laboratory

Orientation is one of the important behaviors of insects during migration. Minor difference in orientation behavior would result in a large discrepancy in migratory trajectories. To establish a method for measuring insect orientations of nocturnal migrants in the laboratory, the present study evaluated the possibility measuring insect orientations of trapped migratory moths of Mythimna separata, Helicoverpa armigera and Agrotis ypsilon using a novel flight simulator. The results indicated that only the population of M. separata had significant orientation, although each individual of these three species was significantly orientated. During the simulated flight, M. separata achieved the longest flight duration and determined their preferred directions quickly with limited turns, thus orientations of M. separata were easy to be measured with the flight simulator (including the direction and duration of flight), and provided a novel experimental tool for understanding the orientation mechanisms of this species in the future. H. armigera had relatively shorter flight duration and unstable preferred direction, and A. ypsilon turned repeatedly and the orientation was highly variable. Therefore, it was not fully convinced that this method is suitable for measuring the orientation of these two species.