广西褐飞虱发生特点及其迁飞路径分析

利用1991-2012年广西龙州、玉林、来宾、永福、兴安植保站褐飞虱灯诱虫情资料，对近22a广西褐飞虱发生特点进行分析，并利用HYSPLIT平台模拟褐飞虱迁入高峰日后向轨迹，研究广西褐飞虱的主要迁入路径。结果表明：（1）近22a来，广西5个代表站褐飞虱的迁入始见期、首次迁入高峰期均呈偏早趋势，提前率分别为1.1d·10a-1和1.8d·10a-1；而迁入终见期呈推迟趋势，5站平均推迟率为2.6d·10a-1。（2）偏南路径（包括西南、正南、东南）是广西各稻区褐飞虱春、夏季迁入的主要路径，占春夏季总迁入过程数的94%以上；偏北路径只发生在桂北地区，不到总数的6%；中南半岛、海南岛和广东省是广西褐飞虱春、夏季迁入的主要虫源地。（3）秋季褐飞虱回迁以东北路径为主，兴安站褐飞虱回迁路径中，东北路径占89%，从广东迁入的路径占11%；而龙州站东北和偏东路径共占83%，偏南路径占17%；玉林、来宾、永福3站秋季迁入峰期不明显；江西、湖南、广东等地的稻区是广西褐飞虱秋季迁入的主要虫源地。（4）当7月850hPa高空以偏南气流为主时，会引发广西褐飞虱的灾变性迁入；当7月850hPa高空以偏北气流为主时，褐飞虱发生偏轻。当9月925hPa高空以偏北气流为主时，利于褐飞虱从湖南、江西等地南迁至广西，广西褐飞虱发生偏重，而以偏南气流为主时，发生则偏轻。

Analysis on Occurrence Pattern and Migratory Paths of Brown Plant hopper in Guangxi Province

Based on the lighting trap catches of brown plant hopper （BPH），Nilaparvata lugens （Stl） data from 5 plant protection stations at Longzhou，Yulin，Laibin，Yongfu and Xingan in the Guangxi Zhuang Autonomous Region during 1991-2012，the BPH occurrence pattern was summarized.The BPH backward trajeclories on peak days was simulated by HYSPLIT and the primary BPH migration paths into Guangxi were analyzed.The results showed that the BPH immigration beginning date and the first immigration peak date from 5 stations were advanced，with the rates of 1.1d·10y-1 and 1.8d·10y-1 respectively in average.But the immigration ending date was postponed， with the rate of 2.6d·10y-1 in average. The southerly path （including the southwest path，the south path and southeast path） was the main path of BPH immigration in spring and summer，and it accounted for more than 94% of the total immigration events.The Indochina Peninsula，Hainan Island and Guangdong Province were the main pest sources of BPH.The back immigration path of BPH in autumn was mainly northeast path，which accounted for 89% of the total immigration events.The main pest sources of BPH immigration in autumn were Jiangxi Province，Hunan Province and Guangdong Province.BPH immigration occurred seriously when the south airflow took the dominant place at 850hPa in July，but BPH immigration decreased remarkable when the north airflow prevailed.Accordingly，when there was the prevailing north airflow at 925hPa in September，it was advantageous to the immigration southward of BPH population into the Guangxi from Jiangxi，Hunan and the other provinces in the north side. Conversely，BPH landing heads reduced obviously when the south airflow prevailed at this level．