粘虫成虫在气流场中飞行行为的观察研究

通过改进悬吊测飞技术、室内风洞和野外雷达相结合的观测方法，研究了粘虫在气流场中的飞行行为特征及其与气流的关系。直筒风洞自由飞行观测的结果表明，粘虫蛾对气流有明显行为反应，表现为头部迎风起飞和迎风飞行的特性；在3.0～5.5 m/s风速下，有92%～94% 的个体可一次逆风飞行通过2 m长的风洞；当风速≥6.0 m/s时，有71.9%的蛾子沿螺旋状的飞行轨迹逆风通过风洞。环形风洞悬吊飞行测试的结果表明，粘虫可逆风飞行的最大风速为7.2 m/s；在风速≤4 m/s条件下，90%以上个体头部迎风飞行或头部朝向与风向成一定的夹角，侧逆风飞行。 雷达观测发现粘虫在空中迁飞过程中具有成层现象，并有较强的秋季回迁定向行为，其头部总是朝向西南；迁飞的最终位移与风向及风速大小有关，迁飞位移速度是飞行速度与风速的矢量和。

Observations on the flight behavior of the oriental armyworm, Mythimna separata(Walker) in airflow

Flight behavior of the oriental armyworm Mythimna separata(Walker) moth in airflow was studied systematically using wind tunnel and scanning entomological radar. The results showed that the moths responded obviously to wind in the cylindrical wind tunnel, and they took off and flew against airflow in flight. When the wind speed was 3.0～5.5 m/s, up to 92%～94% moths tested could fly through the 2 meter wind tunnel; while, only 71.9% tested moths flew helically through the cylindrical wind tunnel against airflow when the wind speed reached to or over 6.0 m/s. In the annular wind tunnel, their maximum flight speed was 7.2 m/s; more than 90% of the tested moths flew with certain angle against airflow when the wind speed was or over 4.0 m/s. Radar observations indicated that the stratification occurred in the course of the Oriental armyworm migration. The moths headed southwest in autumn migration. The flight displacement of the moths was related to wind direction and speed.