中国华南地区稻纵卷叶螟迁飞的一次雷达观测

【目的】研究稻纵卷叶螟（Cnaphalocrocis medinalis Guenée）在华南地区的迁飞行为参数，为其早期预警及有效防控提供依据。【方法】利用毫米波扫描昆虫雷达及相关辅助设备对中国华南地区稻纵卷叶螟的空中飞行参数进行研究，并运用HYSPLIT平台对监测到的迁出种群进行迁飞轨迹分析。【结果】在中国华南地区，稻纵卷叶螟在日落后起飞，20：00左右达到起飞高峰，起飞可持续1 h左右；稻纵卷叶螟迁飞高度主要在1 000 m以下，具有聚集成层现象，可形成2-3层，100-300、400-500 m成层密度较大。成层现象与局部风速极值有关，与风向关系不大，但最大密度并不总是出现在最大风速处。轨迹分析显示，此次从兴安迁出的稻纵卷叶螟蛾经过3次再迁飞，可到达广西河池地区继续繁殖危害，而到达贵州遵义、黔南地区的虫群由于缺乏食物来源无法生存。【结论】稻纵卷叶螟在华南地区的迁飞行为参数与华东地区有所不同。

A Case Study of Radar Observation of the Rice Leaf Folder (Cnaphalocrocis medinalis Guenée) Migration in Southern China

【Objective】The objective of this study is to research on the flight parameters of rice leaf folder (Cnaphalocrocis medinalis Guenée) in southern China, and to provide a basis for effective prevention and control of this pest. 【Method】 The flight parameters of C. medinalis moth were studied by using a millimetric scanning entomology radar and related equipments. The spatio-temporal distribution of landing areas of emigration population was analyzed using HYSPLIT, a software package that simulates migration trajectories. 【Result】 C. medinalis started take-off after sunset, reached the take-off peak at about 20：00, take-off sustained about 1 h. C. medinalis moth generally flew below 1 000 m. It accumulated and formed 2-3-layer dense layers when flew. The insect layer with large density at 100-300 m and 400-500 m could observe every night. The insect layer was coincide closely with partial maximum wind speed and was not conincide with wind direction. However, the biggest density was not always at the height of biggest wind speed. Trajectory analysis showed that the population emmigrating from Xing’an could arrive and survive at Hechi in Guangxi. Because of no suitable rice, the population arriving at Zunyi and Qiannan in Guizhou couldn’t survive. 【Conclusion】 The flight parameters of C. medinalis in southern China were different from those in eastern China.