Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, USA.
Theor Appl Genet. 2011 Nov;123(7):1107-19. doi: 10.1007/s00122-011-1652-2. Epub 2011 Jul 16.
Fusarium head blight (FHB) is a devastating disease of wheat worldwide. Novel sources of resistance are critical for improving FHB resistance levels in wheat. From a large-scale evaluation of germplasm for reactions to FHB, we identified one wheat accession (PI 277012) that consistently showed a high level of resistance in both greenhouse and field experiments. To characterize the FHB resistance in this accession, we developed a doubled haploid (DH) mapping population consisting of 130 lines from the cross between PI 277012 and the hard red spring wheat cultivar 'Grandin'. The DH population was then evaluated for reactions to FHB in three greenhouse seasons and five field environments. Based on a linkage map that consisted of 340 SSR markers spanning 2,703 cM of genetic distance, two major quantitative trait loci (QTLs) for FHB resistance were identified on chromosome arms 5AS and 5AL, with each explaining up to 20 and 32% of the variation in FHB severity, respectively. The two QTLs also showed major effects on reducing the percentage of Fusarium damaged kernels (FDK) and deoxynivalenol (DON) accumulation in seeds. FHB resistance has not previously been reported to be associated with this particular genomic region of chromosome arm 5AL, thus indicating the novelty of FHB resistance in PI 277012. Plant maturity was not associated with FHB resistance and the effects of plant height on FHB resistance were minor. Therefore, these results suggest that PI 277012 is an excellent source for improving FHB resistance in wheat. The markers identified in this research are being used for marker-assisted introgression of the QTLs into adapted durum and hard red spring wheat cultivars.
镰刀菌穗腐病（FHB）是一种世界性的小麦毁灭性疾病。新型的抗性来源对于提高小麦的 FHB 抗性水平至关重要。通过对 FHB 反应的种质进行大规模评估，我们发现一个小麦品系（PI 277012）在温室和田间试验中均表现出高度抗性。为了研究该品系的 FHB 抗性，我们利用 PI 277012 和硬红春小麦品种‘Grandin’杂交，构建了一个包含 130 个株系的加倍单倍体（DH）作图群体。然后，在三个温室季节和五个田间环境中，对 DH 群体进行了 FHB 反应评估。基于包含 340 个 SSR 标记的连锁图谱，覆盖 2703cM 的遗传距离，在 5AS 和 5AL 染色体臂上鉴定到两个与 FHB 抗性相关的主要数量性状位点（QTL），每个 QTL 分别解释了 FHB 严重度变异的 20%和 32%。这两个 QTL 还对降低 FDK 和种子中脱氧雪腐镰刀菌烯醇（DON）积累的比例有较大影响。以前没有报道过 FHB 抗性与 5AL 染色体臂的这一特定基因组区域有关，因此表明 PI 277012 中的 FHB 抗性具有新颖性。植物成熟度与 FHB 抗性无关，株高对 FHB 抗性的影响较小。因此，这些结果表明，PI 277012 是提高小麦 FHB 抗性的一个极好来源。本研究中鉴定的标记正在用于将 QTL 标记辅助导入适应性较强的杜伦和硬红春小麦品种。
