International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, Mexico DF 06600, Mexico.
Int J Mol Sci. 2018 Dec 14;19(12):4054. doi: 10.3390/ijms19124054.
Spot blotch (SB) is an important fungal disease of wheat in South Asia and South America. Host resistance is regarded as an economical and environmentally friendly approach of controlling SB, and the inheritance of resistance is mostly quantitative. In order to gain a better understanding on the SB resistance mechanism in CIMMYT germplasm, two bi-parental mapping populations were generated, both comprising 232 F progenies. Elite CIMMYT breeding lines, BARTAI and WUYA, were used as resistant parents, whereas CIANO T79 was used as susceptible parent in both populations. The two populations were evaluated for field SB resistance at CIMMYT's Agua Fria station for three consecutive years, from the 2012⁻2013 to 2014⁻2015 cropping seasons. Phenological traits like plant height (PH) and days to heading (DH) were also determined. Genotyping was performed using the DArTSeq genotyping-by-sequencing (GBS) platform, and a few D-genome specific SNPs and those for phenological traits were integrated for analysis. The most prominent quantitative trait locus (QTL) in both populations was found on chromosome 5AL at the locus, explaining phenotypic variations of 7⁻27%. Minor QTL were found on chromosomes 1B, 3A, 3B, 4B, 4D, 5B and 6D in BARTAI and on chromosomes 1B, 2A, 2D and 4B in WUYA, whereas minor QTL contributed by CIANO T79 were identified on chromosome 1B, 1D, 3A, 4B and 7A. In summary, resistance to SB in the two mapping populations was controlled by multiple minor QTL, with strong influence from .
斑点叶枯病（SB）是南亚和南美洲小麦的一种重要真菌病害。寄主抗性被认为是控制 SB 的一种经济和环保的方法，抗性的遗传大多是数量性状的。为了更好地了解 CIMMYT 种质中 SB 抗性的机制，生成了两个双亲作图群体，每个群体包含 232 个 F 后代。选用 CIMMYT 的两个优良育种系 BARTAI 和 WUYA 作为抗性亲本，而 CIANO T79 作为两个群体的感病亲本。这两个群体在 CIMMYT 的 Agua Fria 站连续三年（2012⁻2013 至 2014⁻2015 种植季）进行田间 SB 抗性评估。还测定了农艺性状，如株高（PH）和抽穗期（DH）。使用 DArTSeq 基因分型测序（GBS）平台进行基因分型，并整合了一些 D 基因组特异 SNP 和与农艺性状相关的 SNP 进行分析。在两个群体中最显著的数量性状位点（QTL）都位于 5AL 染色体上的 位点，解释了 7⁻27%的表型变异。在 BARTAI 中还发现了 1B、3A、3B、4B、4D 和 5B 染色体以及 WUYA 中的 1B、2A、2D 和 4B 染色体上的次要 QTL，而在 CIANO T79 中发现了 1B、1D、3A、4B 和 7A 染色体上的次要 QTL。总之，两个作图群体对 SB 的抗性由多个微效 QTL 控制， 位点的影响很强。
