入侵川西高原的草地贪夜蛾虫源分析

草地贪夜蛾是2019年入侵我国的重大迁飞性害虫,2019年6月底-7月中旬在川西高原发现草地贪夜蛾幼虫为害。研究川西高原草地贪夜蛾迁入种群虫源地分布及迁飞路径,对丰富草地贪夜蛾迁飞生物学以及川西高原草地贪夜蛾监测预警和防控有重要意义。本文利用基于WRF模式的昆虫三维轨迹分析程序,对入侵川西高原的草地贪夜蛾迁飞路径及天气背景进行了分析。结果表明,6月底-7月中旬川西高原查见的草地贪夜蛾幼虫为6月下旬-7月初迁入成虫繁殖而来。川西高原草地贪夜蛾迁入虫源主要分布在云南西部、西北部,西藏东南部和缅甸北部。草地贪夜蛾可从虫源地随偏西-西南气流经1~3夜迁飞而来,有效迁飞高度为海拔3500~5350 m。降水、下沉气流和低温的综合作用可迫使草地贪夜蛾降落在川西高原。

Source analysis of fall armyworm Spodoptera frugiperda (J.E.Smith) invaded Western Sichuan Plateau

Fall armyworm is a major migratory pest that invaded China in 2019. The larvae of fall armyworm were found in the Western Sichuan Plateau from the end of June to the middle of July. The better understanding of its source areas and migration path will enrich the migration biology of fall armyworm and be beneficial for monitoring and control of this pest. In this paper, the WRF model based 3D trajectory analysis program was used to analyze the migration path and weather background of fall armyworm invaded the Western Sichuan Plateau. The results showed that the larvae of fall armyworm found in the Western Sichuan Plateau in the end of June to the middle of July were offspring of the adult invaded in the late June to the early July. These fall armyworm were mainly came from western and northwestern Yunnan, southeastern Tibet and northern Myanmar and might spend 1-3 nights with the help of the west-southwest airflow. The effective migration height is 3 500-5 350 m above sea level. The combination of precipitation, downdraft and low temperature can force the fall armyworm to land on the Western Sichuan Plateau.