PDF(Pubmed)
Abstract：
Fusarium head blight (FHB) is a disease affecting wheat spikes caused by some Fusarium species and leads to cases of severe yield reduction and seed contamination. Identifying resistance genes/QTLs from wheat germplasm may help to improve FHB resistance in wheat production.
Our study evaluated 205 elite winter wheat cultivars for FHB resistance. A high-density 90K SNP array was used for genotyping the panel. A genome-wide association study (GWAS) from cultivars from three different environments was performed using a mixed linear model (MLM).
Sixty-six significant marker-trait associations (MTAs) were identified (P < 0.001) on fifteen chromosomes that explained the phenotypic variation ranging from 5.4 to 11.2%. Some important new MTAs in genomic regions involving FHB resistance were found on chromosomes 2A, 3B, 5B, 6A, and 7B. Six MTAs at 92 cM on chromosome 7B were found in cultivars from two different environments. Moreover, there were 11 MTAs consistently associated with diseased spikelet rate and diseased rachis rate as pleiotropic effect loci and D_contig74317_533 on chromosome 5D was novel for FHB resistance. Eight new candidate genes of FHB resistance were predicated in wheat in this study. Three candidate genes, TraesCS5D02G006700, TraesCS6A02G013600, and TraesCS7B02G370700 on chromosome 5DS, 6AS, and 7BL, respectively, were perhaps important in defending against FHB by regulating intramolecular transferase activity, GTP binding, or chitinase activity in wheat, but further validation in needed. In addition, a total of five favorable alleles associated with wheat FHB resistance were discovered. These results provide important genes/loci for enhancing FHB resistance in wheat breeding by marker-assisted selection.
Our study evaluated 205 elite winter wheat cultivars for FHB resistance. A high-density 90K SNP array was used for genotyping the panel. A genome-wide association study (GWAS) from cultivars from three different environments was performed using a mixed linear model (MLM).
Sixty-six significant marker-trait associations (MTAs) were identified (P < 0.001) on fifteen chromosomes that explained the phenotypic variation ranging from 5.4 to 11.2%. Some important new MTAs in genomic regions involving FHB resistance were found on chromosomes 2A, 3B, 5B, 6A, and 7B. Six MTAs at 92 cM on chromosome 7B were found in cultivars from two different environments. Moreover, there were 11 MTAs consistently associated with diseased spikelet rate and diseased rachis rate as pleiotropic effect loci and D_contig74317_533 on chromosome 5D was novel for FHB resistance. Eight new candidate genes of FHB resistance were predicated in wheat in this study. Three candidate genes, TraesCS5D02G006700, TraesCS6A02G013600, and TraesCS7B02G370700 on chromosome 5DS, 6AS, and 7BL, respectively, were perhaps important in defending against FHB by regulating intramolecular transferase activity, GTP binding, or chitinase activity in wheat, but further validation in needed. In addition, a total of five favorable alleles associated with wheat FHB resistance were discovered. These results provide important genes/loci for enhancing FHB resistance in wheat breeding by marker-assisted selection.
摘要：
■镰刀菌枯萎病（FHB）是一种影响某些镰刀菌物种引起的小麦穗的疾病，并导致严重的产量下降和种子污染。从小麦种质中鉴定抗性基因/QTL可能有助于提高小麦生产中的FHB抗性。
■我们的研究评估了205个优良冬小麦品种的FHB抗性。高密度90KSNP阵列用于对组进行基因分型。使用混合线性模型（MLM）对来自三个不同环境的品种进行了全基因组关联研究（GWAS）。
■在15条染色体上发现了66个显着的标记-性状关联（MTA）（P<0.001），解释了5.4％至11.2％的表型变异。在2A染色体上发现了一些涉及FHB抗性的基因组区域中的重要新MTA，3B,5B,6A,7B在来自两个不同环境的品种中，在7B号染色体上发现了6个92cM的MTA。此外，有11个MTA与患病的小穗率和患病的轴率一致相关，因为多效性效应基因座和5D染色体上的D_contig74317_533对FHB抗性是新的。本研究在小麦中预测了八个新的FHB抗性候选基因。三个候选基因,染色体5DS上的TraesCS5D02G006700、TraesCS6A02G013600和TraesCS7B02G370700，6AS,7BL,分别,在通过调节分子内转移酶活性防御FHB方面可能很重要，GTP结合，或小麦中的几丁质酶活性，但需要进一步验证。此外,总共发现了与小麦FHB抗性相关的五个有利等位基因。这些结果为通过标记辅助选择增强小麦育种中的FHB抗性提供了重要的基因/基因座。
■我们的研究评估了205个优良冬小麦品种的FHB抗性。高密度90KSNP阵列用于对组进行基因分型。使用混合线性模型（MLM）对来自三个不同环境的品种进行了全基因组关联研究（GWAS）。
■在15条染色体上发现了66个显着的标记-性状关联（MTA）（P<0.001），解释了5.4％至11.2％的表型变异。在2A染色体上发现了一些涉及FHB抗性的基因组区域中的重要新MTA，3B,5B,6A,7B在来自两个不同环境的品种中，在7B号染色体上发现了6个92cM的MTA。此外，有11个MTA与患病的小穗率和患病的轴率一致相关，因为多效性效应基因座和5D染色体上的D_contig74317_533对FHB抗性是新的。本研究在小麦中预测了八个新的FHB抗性候选基因。三个候选基因,染色体5DS上的TraesCS5D02G006700、TraesCS6A02G013600和TraesCS7B02G370700，6AS,7BL,分别,在通过调节分子内转移酶活性防御FHB方面可能很重要，GTP结合，或小麦中的几丁质酶活性，但需要进一步验证。此外,总共发现了与小麦FHB抗性相关的五个有利等位基因。这些结果为通过标记辅助选择增强小麦育种中的FHB抗性提供了重要的基因/基因座。
