在北迁与南迁更替期九种夜蛾的种群结构与迁飞轨迹分析

Population and migration trajectory of nine Noctuidae species in the transitional period between northward and southward migration

【目的】山东省地处粘虫Mythimna separata、棉铃虫Helicoverpa armigera等夜蛾类害虫南北季节性迁飞的重要通道,研究明确夜蛾类害虫在山东省的迁飞规律对于害虫监测预警与防控具有重要意义。【方法】2021年7月11日-8月19日(害虫北迁与南迁更替期)在山东省莒南地区用高空灯对迁飞性昆虫进行了诱捕监测,分析了9种主要夜蛾(棉铃虫、斜纹夜蛾Spodoptera litura、甜菜夜蛾Spodoptera exigua、银纹夜蛾Plusiaagnata、小地老虎Agrotisipsilon、黄地老虎Agrotissegetum、粘虫、二点委夜蛾Athelis lepigone、白条银纹夜蛾Argyrogrammaalbostriata)的种群动态,对雌蛾进行卵巢解剖并分析种群结构变化,结合高空气流解析迁飞轨迹。【结果】7月份西南季风为夜蛾向北迁飞提供了气流条件,7月下旬-8月上旬大约2周的时间内气流发生了快速转变,季风开始南下,为其提供了南迁气流条件,受高空气流的影响,棉铃虫、甜菜夜蛾、粘虫等9种夜蛾类昆虫均有明显的南北迁飞过程,大部分种类在北迁期以迁入种群和本地种群混合发生,在南迁期为外地远距离迁入虫源为主。【结论】充分表明了山东地区既是夜蛾类害虫的春夏繁殖区和东北地区的虫源地,又是从东北回迁虫源的越冬地和继续南迁的通道。

[Objectives]To clarify the migration of noctuid moths in Shandong province,including the armyworm and cotton bollworm.[Methods]During the transitional period between the northward and southward migration of noctuid moths(from July 11 to August 19,2021),migratory insects were trapped and monitored with high-altitude lights in the Junan area.The ovaries of 9 major noctuid moth species(Helicoverpa armigera,Spodoptera litura,Spodoptera exigua,Plusia agnata,Agrotis ipsilon,Agrotis segetum,Mythimna separata,Athelis lepigone and Argyrogramma albostriata)were dissected and their population structure analyzed.The migration trajectory of these moths was investigated in relation to air flow at high altitude.[Results]The southwest monsoon in July provides the airflow conditions required for northward migration.However,from the end of July to early August(within about two weeks),the direction of the air flow changed quickly to that conducive to southward migration.Noctuid moths,such as Helicoverpa armigera,Spodoptera exigua and Mythimna separata,had a clear south-north migration trajectory driven by the airflow at high altitude.The northward migration was a combination of native and immigrant individuals,whereas the southward migration was mainly comprised of immigrants.[Conclusion]This indicates that Shandong province is a breeding area for noctuid pests in spring and summer,and is a source area of these pests for northeast China.It is also the overwintering site for noctuid pests in Northeast China and lies on their southern migration pathway.