Mechanisms Analysis For The Outbreak Of Sogatella Furcifera(Horvath)in Wuling Mountainous Area

The white-backed planthopper Sogatella furcifera(Horváth)(WBPH)is one of the most important migratory pests on rice in Asia.It already has outbreaken for many years since the new century,which has caused heavy losses in rice industry of China.Wuling Mountainous area is located in southwest China,and it is a part of the main round-rout of white-backed planthopper migrating throughout China.So there are so many white-backed planthopper migrated here.In addition,Wuling Mountainous area often occours strong convective weather when the white-backed planthopper endanger the place.This is the reason why WBPH perennial outbreak in this place.So far,there is no detailed research about the current population dynamics,the source areas and landing mechanisms for the WBPH in Wuling Mountainous area.In this study,by using tools of HYSPLIT simulation platform,ArcGIS,GrADS,WRF and R language,the hazard of WBPH in Wuling Mountainous area during 2000 to 2014 were analyzed.So we summed up the endanger law of WBPH about the data in this 15 years of Wuling Mountainous area.And now we make it clear that the distribution of definite mesoscale source areas of WBPH in Wuling Mountainous area.What's more,the study focuse on the multifactorial analysis of space during the migration processes.1.The study on light-trap population of WBPH in Wuling Mountainous areaIn this part,we studied the migration laws by using light-trap data in Wuling Mountainous area from 8 sites during 2000-2014.The results are as follows:(1)the first appearance time of WBPH in Hongjiang and Zhijiang was much earlier than the other regions.(2)The first appearance time of WBPH was much earlier than other years in 2007,especially in Hongjiang,which even arrived two weeks earlier than other 7 sites.(3)The principal damaging generation is not the same in different sites in Wuling Mountainous Area.(4)The occurrence of WBPH was anomalies,obviously in 2009 and 2012.2.The mesoscale source areas of WBPH in Wuling Mountainous areaIn this part,we showed definite mesoscale areas of migrant WBPH during April to July in Wuling Mountainous area from 2000 to 2014.Here coming the results:(1)there are huge diffierent in every month in the source areas.(2)Due to the difference between geographic and topographic,there is great different distribution of wind field in each site.(3)The source areas are not the same as usual,it is further south in April and further north in July.3.Perennial outbreak mechanisms of WBPH in wuling Mountainous areaIn this part,we studied landing mechanisms from many peaks of light-trap in 2007,2009 and 2012.The results are as follows:The Southwest LLJ and the southwest-vortex led to the outbreak of sogatella furcifera(horváth)in wuling mountainous area.