CÉROM, Centre de recherché sur les grains, 740 Chemin Trudeau, Saint-Mathieu-de-Beloeil, QC, J3G 0E2, Canada.
NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK.
Phytopathology. 2019 Oct;109(10):1760-1768. doi: 10.1094/PHYTO-05-19-0159-R. Epub 2019 Sep 5.
Leaf and stripe rust are major threats to wheat production worldwide. The effective, multiple rust resistances present in the Brazilian cultivar Toropi makes it an excellent choice for a genetic study of rust resistance. Testing of DNA from different seed lots of Toropi with 2,194 polymorphic 90K iSelect single nucleotide polymorphism markers identified significant genetic divergence, with as much as 35% dissimilarity between seed lots. As a result, further work was conducted with a single plant line derived from Toropi variant Toropi-6.4. A double haploid population with 168 lines derived from the cross Toropi-6.4 × Thatcher was phenotyped over multiple years and locations in Canada, New Zealand, and Kenya, with a total of seven field trials undertaken for leaf rust and nine for stripe rust. Genotyping with the 90K iSelect array, simple sequence repeat and Kompetitive allele-specific polymerase chain reaction markers resulted in a genetic map of 3,043 cM, containing 1,208 nonredundant markers. Significant quantitative trait loci (QTL) derived from Toropi-6.4 were identified in multiple environments on chromosomes 1B (/), 3B (), 4B (), 5A ( and ), and 5D (). The QTL / colocated with the multi-rust resistance locus , while the QTL located to the locus previously found in a wheat backcross population derived from Toropi. Comparisons of QTL combinations showed to contribute a significantly enhanced leaf rust resistance when combined with or , more so than when and were combined. A strong additive effect was also seen when the stripe rust resistance QTL and were combined.
叶锈病和条锈病是全球小麦生产的主要威胁。巴西品种 Toropi 中存在有效的、多种锈病抗性，使其成为锈病抗性遗传研究的绝佳选择。使用 2,194 个多态性 90K iSelect 单核苷酸多态性标记对来自不同种子批的 Toropi DNA 进行测试，结果表明存在显著的遗传差异，种子批之间的差异高达 35%。因此，进一步对源自 Toropi 变体 Toropi-6.4 的单个植物系进行了研究。利用来自 Toropi-6.4×Thatcher 杂交的 168 个单株衍生的双单倍体群体，在加拿大、新西兰和肯尼亚的多个地点和多年进行了表型分析，共进行了 7 次叶锈病田间试验和 9 次条锈病田间试验。使用 90K iSelect 阵列、简单重复序列和 Kompetitive allele-specific polymerase chain reaction 标记进行基因分型，得到了一个包含 1,208 个非冗余标记的 3,043 cM 的遗传图谱。在多个环境中，从 Toropi-6.4 中鉴定到了显著的数量性状位点（QTL），这些 QTL 位于染色体 1B (/), 3B (), 4B (), 5A (和), 5D (上)。QTL / 与多锈病抗性基因座 colocated ，而 QTL 位于先前在源自 Toropi 的小麦回交群体中发现的基因座上。对 QTL 组合的比较表明，当与 或 组合时， 显著增强了叶锈病抗性，比与 或 组合时更为显著。当条锈病抗性 QTL 与 组合时，也观察到了很强的累加效应。
