Department of Agronomy and Plant Breeding, Faculty of Agricultural Sciences and Engineering, University of Tehran, Karaj, Iran.
Department of Cereal Research, Seed and Plant Improvement Institute, Agricultural Research and Education Organization (AREEO), Karaj, Iran.
BMC Genomics. 2023 Feb 21;24(1):83. doi: 10.1186/s12864-022-09096-1.
Global wheat productivity is seriously challenged by a range of rust pathogens, especially leaf rust derived from Puccinia triticina. Since the most efficient approach to control leaf rust is genetic resistance, many efforts have been made to uncover resistance genes; however, it demands an ongoing exploration for effective resistance sources because of the advent of novel virulent races. Thus, the current study was focused on detecting leaf rust resistance-related genomic loci against the P. triticina prevalent races by GWAS in a set of Iranian cultivars and landraces.
Evaluation of 320 Iranian bread wheat cultivars and landraces against four prevalent rust pathotypes of P. triticina (LR-99-2, LR-98-12, LR-98-22, and LR-97-12) indicated the diversity in wheat accessions responses to P. triticina. From GWAS results, 80 leaf rust resistance QTLs were located in the surrounding known QTLs/genes on almost chromosomes, except for 1D, 3D, 4D, and 7D. Of these, six MTAs (rs20781/rs20782 associated with resistance to LR-97-12; rs49543/rs52026 for LR-98-22; rs44885/rs44886 for LR-98-22/LR-98-1/LR-99-2) were found on genomic regions where no resistance genes previously reported, suggesting new loci conferring resistance to leaf rust. The GBLUP genomic prediction model appeared better than RR-BLUP and BRR, reflecting that GBLUP is a potent model for genomic selection in wheat accessions.
Overall, the newly identified MTAs as well as the highly resistant accessions in the recent work provide an opportunity towards improving leaf rust resistance.
全球小麦生产力受到多种锈病病原体的严重挑战，尤其是来自小麦叶锈菌（Puccinia triticina）的叶锈病。由于控制叶锈病最有效的方法是遗传抗性，因此已经做出了许多努力来揭示抗性基因；然而，由于新的毒力菌株的出现，需要不断探索有效的抗性来源。因此，本研究通过 GWAS 检测了一组伊朗品种和地方品种中与 P. triticina 流行菌株相关的叶锈病抗性相关基因组位点。
对 320 个伊朗面包小麦品种和地方品种对 P. triticina 的四个流行菌系（LR-99-2、LR-98-12、LR-98-22 和 LR-97-12）进行评估表明，小麦品种对 P. triticina 的反应存在多样性。从 GWAS 结果中，在几乎所有染色体的已知 QTL/基因周围定位了 80 个叶锈病抗性 QTL，除了 1D、3D、4D 和 7D。其中，六个 MTA（与 LR-97-12 抗性相关的 rs20781/rs20782；与 LR-98-22 抗性相关的 rs49543/rs52026；与 LR-98-22/LR-98-1/LR-99-2 抗性相关的 rs44885/rs44886）位于先前未报道抗性基因的基因组区域，表明这些新的位点赋予了对叶锈病的抗性。GBLUP 基因组预测模型似乎优于 RR-BLUP 和 BRR，这表明 GBLUP 是小麦品种基因组选择的有力模型。
总的来说，新鉴定的 MTA 以及本研究中高度抗性的品种为提高叶锈病抗性提供了机会。
