Analysis On The Regional Relationship Of Epidemic Of Puccinia Striiformis In China

Stripe rust of wheat, caused by Puccinia striiformis f.sp.tritici, is one of pandemic diseases given severe loss for agriculture in china. In history, the stripe rust of wheat, have four pandemic in 1950,1964,1990,2002. Although we do our best to control the disease pandemic, it seem pandemic interval several years. For probing the disciplinarian of wheat stripe rust on pandemic, chive macroscopic management and super-long predict, it is necessary to research the region relativity on pandemic.Since some ten years, base on effort of resdarcher,we have collected lagar history data,achived many result,so this research collect the data material of many institutes and agrecalture organ for many years,according to history experience and Zhanhong Ma, Shoudin Shi to Puccinia striiformis f.sp.tritici pathogen-oversummering and overwintering region division, choose typical region for example GanShu -TianShui,Shanxi-HanZhong, SiChuan-MaErKang, and choose ShanXi-XiAn,HeNan-ZhengZhou ,the date is enough to research, want to find the region relativety on pandemic.The research main analysis data are disease degree and meteorological data, source from wheat rust area,degree source from . 1987-2002 wheat stripe rust area in country disease degree on wheat stripe rust predict place ,1950-2000 wheat stripe rust area data from the Country Agrinomy Technology spread center.Meteorological data: the data of 194 observation pot from 1951 to 2000 year ground meteorological observation materials from national mereorological center. Choosing several close factor to wheat stripe rust ,rainy, comparative humidity,the wind direct,the average wind speed,the time from March 1 to May 31.After the geographic database of factors related to wheat stripe rust was builded, according to Puccinia striiformis f.sp.tritici pathogen-oversummering and overwintering region division , analysis the relativety of northwest region wheat stripe rust space and disease distribution,include GanShu -TianShui,Shanxi-HanZhong, SiChuan-MaErKang,ShanXi-XiAn,HeNan-ZhengZhou. Since wheat stripe rust is air spread ,so we transfer the meteorological date for average wind speed and biggest wind direct when researching two regions space trend and spread relationship, first using wind energy concept and calculate way, the aim to give wind energy is for reaserching two region relationship , the geographic database and meteorological data is calculating, and it can to give a fix quantify value for the ability of spores spread in space. Calculating wind derict affect data. Some region affect other two regions wind direct data is defined the region wind direct against other two regions clip angle cosin, calculating wind energy data is the region wind speed multiply other two region wind direct affect data, for example Sichuan—MaErKang, GanShu-TianShui,Shanxi-HanZhong, GanShu -TianShui with 30 degree isoceles triangle, GanShu-TianShui to HeNan-ZhengZhou slope is 0.086331,radian 0.086117,to ShanXi-XiAn slope is -0.13559, radian is -0.13477. Sichuan—MaErKang wind speed is V, to Gansu Tianshui and Shanxi Hanzhong, the wind energy data calculate formula are:Analysis the two region wheat stripe rust pandemic relativety, to affecting actors use main component analysis and Bayes gradual tropic methods, preliminary clear the relativity of center region GanShu-TianShui against to SiChuan-MaErKang and ShanXi HanZhong, demonstrate the wheat stripe rust pandemic in GanShuTianShui has extremely affect to SiChuan-MaErKang and HeNan-ZhengZhou, for SiChuan-MaErKang, the Resubstitution accuracy is 100 percent, Cross-validation accuracy is 81.82 percent. HeNan-ZhengZhou the Resubstitution accuracy is 92.31 percent, Cross-validation accuracy is 74.36 percent, but to Shanxi-HanZhong and ShanXi-XiAn, the relativety is low. The research is benefit for middle and long predict of wheat stripe rust,saving cost for inverstigating, providing the decision -making for wheat produce branch and plant protect branch in IPM.