Xie Dongwei, Dai Zhigang, Yang Zemao, Sun Jian, Zhao Debao, Yang Xue, Zhang Liguo, Tang Qing, Su Jianguang
Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, China.
Institute of Industrial Crops, Heilongjiang Academy of Agricultural Sciences, Harbin, China.
Front Plant Sci. 2018 Jan 9;8:2232. doi: 10.3389/fpls.2017.02232. eCollection 2017.
Flax ( L.) is an important cash crop, and its agronomic traits directly affect yield and quality. Molecular studies on flax remain inadequate because relatively few flax genes have been associated with agronomic traits or have been identified as having potential applications. To identify markers and candidate genes that can potentially be used for genetic improvement of crucial agronomic traits, we examined 224 specimens of core flax germplasm; specifically, phenotypic data for key traits, including plant height, technical length, number of branches, number of fruits, and 1000-grain weight were investigated under three environmental conditions before specific-locus amplified fragment sequencing (SLAF-seq) was employed to perform a genome-wide association study (GWAS) for these five agronomic traits. Subsequently, the results were used to screen single nucleotide polymorphism (SNP) loci and candidate genes that exhibited a significant correlation with the important agronomic traits. Our analyses identified a total of 42 SNP loci that showed significant correlations with the five important agronomic flax traits. Next, candidate genes were screened in the 10 kb zone of each of the 42 SNP loci. These SNP loci were then analyzed by a more stringent screening via co-identification using both a general linear model (GLM) and a mixed linear model (MLM) as well as co-occurrences in at least two of the three environments, whereby 15 final candidate genes were obtained. Based on these results, we determined that and are candidate genes for plant height, and are candidate genes for the number of branches, and are candidate genes for the number of fruits, and is a candidate gene for the 1000-seed weight. We propose that the identified SNP loci and corresponding candidate genes might serve as a biological basis for improving crucial agronomic flax traits.
亚麻（L.）是一种重要的经济作物，其农艺性状直接影响产量和品质。由于与农艺性状相关或被鉴定具有潜在应用价值的亚麻基因相对较少，亚麻的分子研究仍然不足。为了鉴定可用于关键农艺性状遗传改良的标记和候选基因，我们检测了224份核心亚麻种质样本；具体而言，在三个环境条件下研究了包括株高、工艺长度、分枝数、果实数和千粒重等关键性状的表型数据，然后采用特异性位点扩增片段测序（SLAF-seq）对这五个农艺性状进行全基因组关联研究（GWAS）。随后，利用研究结果筛选与重要农艺性状显著相关的单核苷酸多态性（SNP）位点和候选基因。我们的分析共鉴定出42个与五个重要亚麻农艺性状显著相关的SNP位点。接下来，在42个SNP位点各自的10 kb区域内筛选候选基因。然后通过使用一般线性模型（GLM）和混合线性模型（MLM）进行共鉴定以及在三个环境中的至少两个环境中共出现的方式对这些SNP位点进行更严格的筛选，从而获得了15个最终候选基因。基于这些结果，我们确定 和 是株高的候选基因， 和 是分枝数的候选基因， 和 是果实数的候选基因， 是千粒重的候选基因。我们认为，鉴定出的SNP位点和相应的候选基因可能为改良关键亚麻农艺性状提供生物学基础。
