小麦条锈菌中国鉴别寄主维尔中抗条锈病基因YrVir1的微卫星标记

 【目的】明确中国小麦条锈菌重要鉴别寄主维尔的抗条锈病基因及其遗传特点，建立与其连锁的微卫星标记，将病菌小种监测和抗病性分析提高到基因水平。【方法】由维尔为基因供体转育而成的含有小麦重要抗条锈基因YrVir1的近等基因系Taichung29*6/YrVir1，用小麦条锈菌单胞菌系2E16对近等基因系Taichung29*6/YrVir1、轮回亲本Taichung29及其杂交后代进行遗传分析；选用YrVir1所在2B染色体上的141对引物对近等基因系和轮回亲本的基因组DNA进行SSR分析。【结果】近等基因系Taichung29*6/YrVir1对2E16的抗病性由1对显性基因控制；引物Xbarc349在近等基因系与轮回亲本间稳定扩增出特异性DNA片段，同时在近等基因系和基因供体维尔间存在相同扩增片段，经F2代群体200个抗、感单株检测证实，Xbarc349标记位点与抗条锈病基因YrVir1连锁，遗传距离为4.2 cm。【结论】Xbarc349引物扩增出的特异性DNA片段可作为抗条锈病基因YrVir1的SSR标记；根据小麦SSR遗传图谱，将YrVir1基因定位在小麦2B染色体上。

SSR Molecular Tapping of Stripe Rust Resistance Gene YrVir1 in Chinese Wheat Differential Host Virgilio

【Objective】The wheat cultivar Virgilio is one of the wheat stripe rust differential hosts in China, it is very important to genetically characterize its stripe rust resistance genes. By developing the molecular markers linked to the resistance genes, we can detect the epidemics of stripe rust races and analyze wheat resistance on a molecular level. Meanwhile we map a stripe rust resistance gene YrVir1 in Virgilio using near-isogenic lines(NILs) Taichung29*6/YrVir1.【Method】We made a cross between cultivar Taichung29 and the resistance gene donor Virgilio, and developed the near-isogenic lines(NILs) Taichung29*6/YrVir1. The resistance of near-isogenic lineTaichung29*6/YrVir1, Taichung29 and their F2 progenies was tested by inoculating with stripe rust (Puccinia striiformis f. sp. tritici) single-spore isolate 2E16. We mapped the gene YrVir1 with 141 pairs SSR primers on wheat chromosome 2B.【Result】The resistance to 2E16 in Taichung29*6/YrVir1 was determined by a single dominant gene; a specific DNA band was amplified between Taichung29*6/YrVir1, Virgilio and Taichung29 by PCR with the primer Xbarc349. The genetic linkage was tested on 200 F2 plants, and the microsatellite marker Xbarc349 was linked to the resistance gene YrVir1, its genetic distance is 4.2cM.【Conclusion】Xbarc349 was regarded as SSR marker linked to stripe rust resistance gene YrVir1 in Chinese wheat differential host Virgilio. According to wheat SSR genetics map, the resistance gene YrVir1 was located on wheat chromosome 2B.