| Stripe rust of wheat, caused by Puccinia striiformis f.sp. tritici, is one of pandemic diseases. The climatic regionalization for the areas of oversummering and overwintering of P. striiformis was performed using Geographic Information System (GIS) and Geostatistics technology after the geographic database of factors related to wheat stripe rust was builded. Additionally the spatial pattern of wheat stripe rust at large scale was analyzed using the same methods. The research made it clear that climatic regions of oversummering and (or) overwintering of P. striiformis based on temperature limited were showed on maps. It will benefit making the management program of wheat stripe rust and performing further investigation on the oversummering and overwintering zones of P. striiformis.Based on percentage of the maximum two average temperatures in a ten-day period in July and August that are under 23℃,22℃,21℃, 20℃ respectively during the years of 1960~2001 as the primary index for regionalizing and relevant wheat-growth information, the study about the climatic region indicated that the interpolated map using Kring was best when the limited temperature is 22℃. With the acceptance of the tolerance in some degree, the boundary where the percentage of the maximum two average temperatures that are under 22℃ is 25% can differentiate the oversummering region and non-oversummering region. The maps that were made by using interpolation based on Digital Elevation Model for the maximum average temperature in a ten-day period in July and August during 1960~2001(Tmax) revealed mass oversummering area under suspicion. The zone where the the most lowest month temperature is among 20℃~23℃ was consistent with the zone where the percentage is 25%~50% and can be considered as the boundary. Oversummering areas of P. striiformis in Tibet, Qinghai, Gansu, Shaanxi, Sichuan, Guizhou and Yunnan are conjunct at the view of the high-limit temperature. Oversummering areas of P. striiformis in Hebei, Shanxi, Inner Mongolia are congregate, but in other places such as western Hubei, the abuttal of Shannxi with Chongqing or Sichuan, etc., are more sporadic. All locations of oversummering of P. striiformis that were validated are in the oversummering region based on the temperature limited. There are many suspicious locations of oversummering of P. striiformis.The maps were made according to percentage of the most lowest month temperature in winter (December in front year and January in this year) that are above -5℃,-6℃,-7℃,-9℃,-7℃ respectively during the years of 1960~2001 as the primary index for regionalizing.The study on the overwintering region of P. striiformis showed that the regionalization map is best when the limited temperature is -7℃, followed by -6℃ and -5℃. The maps that were made by using interpolation based on digital elevation model for thet lowest month temperature in winter during 1960~2001. The result indicated that the zone where the the lowest month temperature is among -7℃~-5℃ was consistent with the zone where the percentage is 70% ~ 85% and can be considered as the boundary of overwintering and non-overwintering regions. The boundary was consisted with the former boundary (Huangling-Jiexiu-Shijiazhuang-Dezhou) of overwintering of P. striiformis in eastern wheat area made by formersin some degree. The difference is that the northern location is Beijing not Dezhou in Shandong Province in the boundary affirmed in this study. In addition, the district of Linxia, Lintao, Hualong, Jinghe, Wushu counties and Tulufan, etc., may be the overwintering area of P. striiformis.Based on climatic maps of the oversummering and overwintering of P. striiformis. The regions where limited temperature is suitable to pathogen oversummering and overwintering indicated that some wheat planted areas in Yunnan, Tibet, southern Gansu,southwest Sichuan,northwest Sichuan, Zhaosu and Lileke in middle Xinjiang, Wuqia in southwest Xinjiang,etc.,can have infection circle regions of P. striiformis,The spatial analysis of wheat...
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