| The wheat stripe rust was a fungal disease on leaves caused by Puccinia striiformis f.sp tritici, and it was the most destructive disease that affects wheat production security in China. Wheat stripe rust has historically burst several times and caused severe seed yield loss. The wide application of resistant varieties on large scale in practice was one of the most economical and effective measures to control it. In China, a large number of wheat landraces have been preserved, which possessed abundantly genetic diversity, including many stripe rust resistance genes. It is of great significance to explore the resistance genetic resources from the landraces and use them practically in wheat resistance breeding and stripe rust control by resistance gene overall arrangement in an area.In this study, we collected 684 wheat landraces from the epidemic areas of stripe rust and then obtained 163 high level resistance or immune landraces to stripe rust by resistance identification, of which 119 adult plant resistant and 42 overall (or seedling) resistant. The resistance landraces accounted for 23.8% of the total used, and the number of adult plant resistant landraces was 17.4%, overall resistant ones 6.1%.Based on general hybridization genetic analysis, we analyzed the genetic characteristics of 5 adult plant resistant landraces to the race CYR32 of P. striiformis f.sp tritici. The landrace Huanxiangtou(3), Baimai(1-3), Baimai(2-1) and Baimangmai to CYR32 was controlled by 1 recessive gene respectively,and resistance Hongjianermai to CYR32 was controlled by 1 dominant gene and 2 complementary recessive genes.The two seedling resistant landraces Hongsuotiao and Baimazha were analyzed with gene postulation method to predict the resistance genes contained. The results showed that both were resistant to most of the 25 races or isolates of P. striiformis used, including 75078,85019,74187,59791,61009,2E16,79009,78028,58893,Su-1,60105,86094,76088,78080,86106,68009,72107,CYR17,CYR26,CYR27,CYR28,CYR29,CYR31,CYR32 and CYR33.These two landraces may be postulated to contain new resistance genes. Besides, the genetic characteristics of the two seedling resistant landraces Hongsuotiao and Baimazha were analyzed to 3 races CYR31, CYR32and CYR33 respectively using their F2 populations. We found that resistant Hongsuotiao to CYR31 was controlled by 2 recessive independent or overlap genes, and controlled by 1 recessive gene for CYR32 and CYR33 respectively, and resistant Baimazha to CYR31was controlled by two dominant complementarity genes,and to CYR32,it was under control of 1 dominant gene respectively, but its resistance to CYR33 was by 2 recessive independent or overlap genes.The close linked molecular marker of resistant Baimangmai to CYR32 was developed using SSR method. Wheat 640 microsatellite primers were used to screen the SSR marker linked to the adult plant resistance gene of Baimangmai by PCR with Baimangmai and Taichung29 genomic DNA. We found a specific DNA band was produced between the resistant and susceptible parent by PCR with Xwmc477 SSR primer on wheat chromosome 2B. We also tested the Xwmc477 primer on the 411 F2 plants and proved that it linked to the adult plant resistance gene YrBm in Baimangmai, and its genetic distance to the YrBm locus was 9.1cM. According to wheat SSR genetic map, YrBm was locused on chromosome 2B. Briefly, these results in this study will benefit the selection, transference and function research of adult plant or seedling resistance genes in the wheat landraces.
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