Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
Sci Rep. 2020 Dec 17;10(1):22113. doi: 10.1038/s41598-020-78679-3.
TSD276-2, a wheat genetic stock derived from the cross Agra Local/T. spelta 276 showed broad spectrum resistance against leaf rust pathogen. Genetic analysis was undertaken using F, F, F and BCF generations derived from the cross TSD276-2/Agra Local. The results revealed a single recessive gene for leaf rust resistance, tentatively named as LrTs in TSD276-2. Molecular mapping of leaf rust resistance gene LrTs in TSD276-2 was done using SNP-based PCR and SSR markers. For Bulked Segregant Analysis (BSA), two bulks viz. resistant bulk and susceptible bulk, and the parents TSD276-2 and Agra Local were genotyped for SNPs using AFFYMETRIX 35K Wheat Breeders' AXIOM array. T. spelta 276 was also genotyped and used as a check. BSA indicated that the gene for leaf rust resistance in TSD276-2 is located on chromosome arm 1DS. Putatively linked SNPs on chromosome arm 1DS were converted into PCR-based markers. Polymorphic SSR markers on chromosome arm 1DS were also identified. Final linkage map was constructed using one SNP-based PCR and three SSR markers. The rust reaction and chromosomal location suggest that LrTs is a new leaf rust resistance gene which may be useful in broadening the genetic base of leaf rust resistance in wheat.
TSD276-2 是一种源自 Agra Local/T. spelta 276 杂交的小麦遗传品系，表现出对叶锈病病原菌的广谱抗性。利用 TSD276-2/Agra Local 杂交产生的 F1、F2、F3 和 BCF 代进行遗传分析。结果表明，TSD276-2 中存在一个对叶锈病抗性的隐性单基因，暂命名为 LrTs。利用 SNP 标记的 PCR 和 SSR 标记对 TSD276-2 中的叶锈病抗性基因 LrTs 进行分子作图。利用 AFFYMETRIX 35K Wheat Breeders' AXIOM 阵列对两个品系（抗品系和感病品系）和亲本 TSD276-2 和 Agra Local 进行 SNP 基因型分析，进行 Bulked Segregant Analysis (BSA)。同时对 T. spelta 276 进行基因分型并作为对照。BSA 表明，TSD276-2 中对叶锈病的抗性基因位于 1DS 染色体臂上。1DS 染色体臂上的假定连锁 SNP 被转化为基于 PCR 的标记。还鉴定了 1DS 染色体臂上的多态性 SSR 标记。利用一个 SNP 标记的 PCR 和三个 SSR 标记构建最终的连锁图谱。锈病反应和染色体定位表明，LrTs 是一个新的叶锈病抗性基因，可能有助于拓宽小麦叶锈病抗性的遗传基础。
