中梁12小麦抗条锈病基因遗传分析与SSR分子定位

中梁12具有抗逆性强、适应性广、抗条锈性强等许多优良的生物学特性。为明确其抗条锈性及遗传规律,利用当前流行的中国条锈菌小种CYR30对抗病品种中梁12与感病品种铭贤169及其杂交后代代F1、F2、F3和BC1代进行苗期抗条锈性遗传分析,并对其抗条锈基因进行SSR分子标记。结果表明,中梁12对CYR30小种具有良好的抗性,由1对显性基因控制,暂命名为YrZh12。该基因与位于小麦7AL染色体上的4个SSR位点Xwmc695、Xcfd20、Xbarc121和Xbarc49连锁,其中最近的侧翼位点为Xcfd20和Xbarc121,其遗传距离分别是3.1cM和4.9cM。系谱分析YrZh12基因可能来自抗引655,由于7AL染色体上没有其他抗条锈病基因,YrZh12可能是一个抗条锈病的新基因。

Genetic Analysis and SSR Molecular Mapping of Stripe Rust Resistance Gene in Wheat Cultivar Zhongliang 12

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most widespread and destructive wheat diseases worldwide. Resistance breeding is constantly pursued for decades to tackle the variations of prevalent Pst races. Zhongliang 12 has strong resistance to abiotic stresses, wide adaptability, higher resistance to stripe rust, excellent biological characteristics. To identify the resistance gene(s) against stripe rust, we crossed Zhongliang 12 with the susceptible genotype Mingxian 169, and tested F₁, F₂, F2:3, and BC₁ progenies with Chinese race CYR30 at seedling stage in greenhouse. Then, SSR techniques were used to screen molecular markers linked to the gene conferring resistance to CYR30 in Zhongliang 12. The genetic analysis results showed that Zhongliang 12 displayed resistance to epidemic yellow rust races in China when tested with five races of stripe rust and had one dominant gene conferring resistance to races CYR30. Four simple sequence repeat (SSR) markers located on chromosome arm 7AL, Xwmc695, Xcfd20, Xbarc121 and Xbarc49, were linked to YrZh12 with the nearest flanking markers of Xcfd20 and Xbarc121. The genetic distances were 3.1 cM to Xcfd20 and 4.9 cM to Xbarc121. Based on chromosomal location and pedigree analysis, YrZh12 was a novel resistance gene to stripe rust.