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【目的】滇东南地区位置特殊，地形复杂，是白背飞虱Sogatella furcifera (Horváth)迁入云南的重要通道之一，早期迁入种群虫源及其降落机制的阐述将为白背飞虱的异地预测提供理论依据。【方法】（1）用HYSPLIT对滇东南地区富宁、麻栗坡、丘北和广南4个站点2008—2012年4—5月白背飞虱迁入高峰日做轨迹分析以阐明其虫源区分布。（2）用GrADS分析NCEP的再分析格点数据以形成各迁入峰期的风温场，阐释迁入峰得以形成的气象背景和降落机制。【结果】（1）滇东南白背飞虱早期迁入种群虫源地主要分布在越南和老挝北部，部分来自于缅甸中北部及掸邦高原、泰国北部、滇西和滇西南。其中，4月份以缅甸和金三角为主，5月份则主要来自越南和老挝北部。（2）影响白背飞虱降落的因子中，风切变、低温屏障、降雨和下沉气流分别占75.9%、56.5%、31.8%和25.2%。【结论】滇东南白背飞虱早期迁入虫源主要来自中南半岛，风切变、低温屏障、降雨和下沉气流四者共同作用形成了白背飞虱在滇东南的频繁迁入。“,”[Objectives] The complicated terrain of southeastern Yunnan is an important pathway for the spring migration of the white-backed planthopper (WBPH), Sogatella furcifera (Horváth). Determining the source area and factors that induce the mass landing of early migrant WBPH is important for forecasting outbreaks of this pest. [Methods] (1) The origins of WBPH captured in light-traps in Funing, Malipo, Guangnan and Qiubei, during each peak period of abundance in April and May from 2008 to 2012 were tracked by trajectory analysis with HYSPLIT. (2) Detailed GrADS analysis of NCEP grid data during periods of peak light trap catch abundance was used to reveal the atmospheric conditions during WBPH immigration and the climatic factors associated with mass landing. [Results] (1) Northern Vietnam and northern Laos are the major source areas of immigrating WBPH in southeastern Yunnan, but some early immigrants in April generally come from mid-north Myanmar and the Shan plateau, northern Thailand (Golden Triangle) and southwestern Yunnan. (2) Wind shear, low temperature, precipitation and downdrafts are the principal factors that induce the large scale mass landing of WBPH, accounting for 75.9%, 56.5%, 31.8 and 25.2%of immigration events, respectively. [Conclusion] The source areas of WBPH immigrants during April and May in southeastern Yunnan are generally in the Indo-Chinese Peninsula. Synergy between wind shear, low temperature, heavy rainfalland downdrafts plays a critical role in immigration events.