人工合成小麦CI191抗条锈病基因的鉴定及分子标记定位

Molecular Tagging of a Stripe Rust Resistance Gene in a Triticum durum-Aegilops squarrosa Synthetic Wheat CI191

抗病性鉴定结果表明,硬粒小麦-粗山羊草人工合成小麦CI191(CPI/GEDIZ/3/GOO//JO69/CRA/4/AE.SQ629),对我国曾经或现在流行的小麦条锈菌生理小种CY28、CY29、CY30、CY31、CY32和水源11致病类型4表现免疫或近免疫。基因推导结果显示,CI191对条锈菌的反应型不同于24份已知抗条锈病基因品种(系),对21个条锈菌生理小种表现抗性,对条锈病菌生理小种86107表现感病反应型(IT3)。对CI191/铭贤169杂交组合的正交、反交的F1材料以及F2代群体进行抗病鉴定与遗传分析,结果表明,CI191对条锈菌小种CY31的抗性受细胞核内的显性单基因控制。利用集群分离分析法(BSA)和简单重复序列(SSR)分子标记分析,发现7个SSR标记与YrC191连锁。构建了包含YrC191的SSR标记遗传图谱,其中Xbarc240与YrC191共分离,Xcfd65、Xbarc187、Xgwm18、Xgwm11位于Xbarc8与YrC191的同侧,与YrC191间遗传距离3.2cM,Xbarc8与YrC191间遗传距离为1.6cM,Xwmc419位于YrC191另一侧、遗传距离为3.1cM。根据SSR分子标记的遗传图谱和在中国春的缺体-四体和双端体的定位结果,将YrC191定位到小麦染色体1BS上。YrC191基因的4个SSR标记和Yr26的1个STS标记可以明显地区分YrC191与染色体1BS上的其他抗条锈病基因,如Yr24、Yr26/YrCH42、Yr10、Yr15和YrC142等。

Stripe rust, caused by Puccinia striiformis f. sp. tritici （Pst）, is one of the most serious fungal diseases in wheat worldwide. To diversify the resistance resources, a resistance synthetic wheat CI191 （CPI/GEDIZ/3/GOO//JO69/CRA/ 4/AE.SQ629） has been mined from 94 accessions of Triticum durum-Aegilops squarrosa synthetic wheat introduced from CYMMT. CI191 show highly resistant to six Pst races prevailing in Chinese, such as CY28, CY29, CY30, CY31, CY32, and CY-Su11-4. Based on the responses of CI191 nd 24 wheat materials possessing known stripe rust resistance genes to 22 Pst races, we postulated CI191 was different from all the known resistant genes. According to analysis of inherited mode, the resistance gene in CI191 was controlled by a single dominate gene, tentatively designated YrC191. Using the cross between CI191 and Mingxian 169 （a sensitive wheat cultivar to Pst races）, the F2 segregation population and the bulked segregant pools were established to screen the the simple sequence repeat （SSR） markers linked to YrC191. Seven SSR markers were found to be linked with YrC191 in the alignment of Xwmc419-YrC191/ Xbarc240-Xbarc8-Xcfd65/Xbarc187/Xgwm18/Xgwm11. YrC191 was cosegrated withthe marker Xbarc240, flanked by the closest linked markers Xbarc8 and Xwmc419 with the relative genetic distances of 1.6 cM and 3.1 cM, respectively. Using Chinese Spring nullisomic-tetrasomics and ditelosomic lines of homoeologous group 1, Xcfd65, Xgwm18, Xgwm11, Xbarc187, and Xwmc419 markers were physically mapped on the chromosome arm 1BS, and YrC191 was also located on 1BS. Four SSR markers linked tightly with YrC191 and 1 sequence tagged site （STS） marker for Yr26 could discriminate YrC191 from the other resistant genes on 1BS, such as Yr24, Yr26, Yr10, Yr15, YrCH42, and YrC142. The resusltes suggested that YrC191 may be a novel resistance gene to Pst.