The Federal Research Center Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
Kurchatov Genomics Center Institute of Cytology and Genetics SB RAS, Novosibirsk, 630090, Russia.
BMC Plant Biol. 2020 Oct 14;20(Suppl 1):135. doi: 10.1186/s12870-020-02333-3.
Leaf rust (Puccinia triticina Eriks.) is one of the most dangerous diseases of common wheat worldwide. Three approaches: genome-wide association study (GWAS), marker-assisted selection (MAS) and phytopathological evaluation in field, were used for assessment of the genetic diversity of Russian spring wheat varieties on leaf rust resistance loci and for identification of associated molecular markers.
The collection, consisting of 100 Russian varieties of spring wheat, was evaluated over three seasons for resistance to the native population of leaf rust specific to the West Siberian region of Russia. The results indicated that most cultivars showed high susceptibility to P. triticina, with severity ratings (SR) of 60S-90S, however some cultivars showed a high level of leaf rust resistance (SR < 20MR-R). Based on the results of genome-wide association studies (GWAS) performed using the wheat 15 K genotyping array, 20 SNPs located on chromosomes 6D, 6A, 6B, 5A, 1B, 2A, 2B and 7A were revealed to be associated with leaf rust resistance. Genotyping with markers developed for known leaf rust resistance genes showed that most of the varieties contain genes Lr1, Lr3a, Lr9, Lr10, Lr17a, Lr20, Lr26 and Lr34, which are not currently effective against the pathogen. In the genome of three wheat varieties, gene Lr6Ai = 2 inherited from Th. intermedium was detected, which provides complete protection against the rust pathogen. It has been suggested that the QTL mapped to the chromosome 5AS of wheat cultivar Tulaikovskaya-zolotistaya, Tulaikovskaya-10, Samsar, and Volgouralskaya may be a new, previously undescribed locus conferring resistance to leaf rust. Obtained results also indicate that chromosome 1BL of the varieties Sonata, Otrada-Sibiri, Tertsiya, Omskaya-23, Tulaikovskaya-1, Obskaya-14, and Sirena may contain an unknown locus that provides a resistance response to local population.
This study provides new insights into the genetic basis of resistance to leaf rust in Russian spring wheat varieties. The SNPs significantly associated with leaf rust resistance can be used for the development and application of diagnostic markers in marker-assisted selection schemes.
叶锈病（Puccinia triticina Eriks.）是全球普通小麦最危险的病害之一。本研究采用全基因组关联研究（GWAS）、标记辅助选择（MAS）和田间植物病理学评估三种方法，评估了俄罗斯春小麦品种在叶锈病抗性基因座上的遗传多样性，并鉴定了相关的分子标记。
该研究收集了 100 个俄罗斯春小麦品种，在三个季节对俄罗斯西西伯利亚地区当地叶锈病群体的抗性进行了评估。结果表明，大多数品种对 P. triticina 表现出高度的敏感性，严重度评分（SR）为 60S-90S，然而一些品种表现出高水平的叶锈病抗性（SR<20MR-R）。基于使用小麦 15K 基因分型阵列进行的全基因组关联研究（GWAS）的结果，在染色体 6D、6A、6B、5A、1B、2A、2B 和 7A 上发现了 20 个与叶锈病抗性相关的 SNP。用开发的已知叶锈病抗性基因标记进行基因分型表明，大多数品种含有 Lr1、Lr3a、Lr9、Lr10、Lr17a、Lr20、Lr26 和 Lr34 基因，这些基因目前对病原体无效。在三个小麦品种的基因组中，检测到来自 Th. intermedium 的基因 Lr6Ai=2 的遗传，该基因对锈病病原体提供完全保护。研究表明，在小麦品种图拉伊科夫斯卡娅-佐洛蒂亚斯塔、图拉伊科夫斯卡娅-10、萨姆萨尔和沃尔古尔尔斯卡娅的 5AS 染色体上定位的 QTL 可能是一个新的、以前未被描述的位点，赋予对叶锈病的抗性。研究结果还表明，品种 Sonata、Otrada-Sibiri、Tertsiya、Omskaya-23、Tulaikovskaya-1、Obskaya-14 和 Sirena 的 1BL 染色体可能含有一个未知的位点，对当地种群的抗性反应。
本研究为俄罗斯春小麦品种对叶锈病的遗传基础提供了新的见解。与叶锈病抗性显著相关的 SNP 可用于开发和应用标记辅助选择方案中的诊断标记。
