2008年广西北部湾稻区稻飞虱初迁入过程分析

2008年2月,我国南方和越南北方普遍遭遇了罕见的低温冻害,褐飞虱Nilaparvata lugens(Stl)与白背飞虱Sogatella furcifera(Horváth)越冬虫量大大减少,而广西北部湾稻区在3—4月却出现了大规模的稻飞虱迁入峰。结合2008年越冬考察、灯下监测以及田间系统调查结果,通过HYSPLIT模型与GrADS软件对此阶段出现的稻飞虱大规模迁入过程进行轨迹模拟与天气学背景分析,得出以下结论:(1)2008年广西早期迁入稻飞虱虫源与越南北部虫源关系不大,主要来自越南中部及老挝南部;(2)850hPa高空温度较高,低空急流频繁,以及过早出现的台风是造成钦州4月份稻飞虱大规模远距离迁入的最主要原因。因此,除越南北部红河三角洲地区外,为我国华南稻区提供早期迁入虫源的越南中部稻区更值得关注。

Analysis on the early immigration of rice planthoppers in southern Guangxi in 2008

Southern China experienced unusually cold conditions in February 2008 which caused an obvious decline in the number of brown planthoppers（BPH,Nilaparvata lugens（Stl）） and white-backed planthoppers（WBPH,Sogatella furcifera（Horváth）） overwintering in the region.However,mass immigration of WBPH occurred in late March and April 2008 in the Guangxi Zhuang Autonomous Region.Based on the analysis of daily light-trap catches,field surveys,overwintering,immigration trajectory simulation and meteorological background analysis,the following conclusions can be drawn：（1） The main source areas of the early immigration of WBPH into Qinzhou in 2008 were in central Vietnam and southern Laos,with very few sites in northern Vietnam.（2） High temperature at 850 hPa,lower level jet stream winds and premature typhoons were the key factors affecting the settlment of both BPH and WBPH in Qinzhou.Therefore,central as well as northern Vietnam must be regarded as potential sourced of rice planthoppers in southern China.