【摘要】 常年3月下旬褐飞虱在我国的广西区西南南部、广东省西南部和云南省南部始见。随着时间的推移，始见湖北界不断向东向北呈扇形扩展；年间有—定的差异月时在110°E以西地域比以东地域北进速度要快一些。分析表明，4～6月在28°N、103°E附近的西南抵涡的形成和移动方位和始见期北界的移动关系密切。更多还原

【Abstract】 The brown planthopper (BPH) starts to immigrate into the southwestern part of Guangxi, the southwestern part of Guangdong and the southern pat of Yunnan in late of March every year in China. As the seasons progress,the front of initial immigration periods moves as a V-shape extended toward north and east directions; and this movement alterable between years, in the mean time the movement speed of the front in the area which west to the 110° E is faster than other areas. Ease on the analysis there are high correlation between the front movement and the generation and development of the southwest low vortex that located in 28° N, 103° E.更多还原