BACKGROUND As waxy maize is considered a key economic crop in Korea, an understanding of its genetic variation and differentiation is fundamental for the selective plant breeding. The maize genome is primarily composed of transposable elements, for which large and stable insertions generate variations that reflect selection during evolution. OBJECTIVES This study was to elucidate the genetic diversity based on the contribution of TEs and to investigate the effect of Mu transposition on the genetic divergence of waxy and common maize. We also performed an association analysis on these inbred lines to determine the Mu insertions associated with agronomic traits. METHODS In this study, we utilized a Mutator-based transposon display method to study the genetic diversity and population structure of 40 waxy and 40 common inbred lines of maize in the Gangwon Agricultural Research and Extension Services collection at the Maize Research Institute. RESULTS We detected polymorphisms in 86.33% of 278 Mutator (Mu) anchored loci, reflecting the activity of the Mu element and its contribution to genetic variation. Common maize showed a substantial amount of genetic diversity, which was greater than that observed in waxy maize. Principal-coordinate and neighbor-joining cluster analyzes consistently supported the presence of two genetically distinct groups. However, the distribution of genetic variation within the populations was much higher than the genetic differentiation among the populations. To explore the contribution of the Mu element to phenotypic variation, we analyzed the associations with ten important agronomical traits. On the basis of the combined results from two models (QGLM and Q + KLM), we found significant associations between seven Mu loci and four different traits. CONCLUSIONS These results will assist waxy maize breeders in choosing parental lines and be useful for marker-assisted selection.

中文翻译：

---

糯性和普通玉米突变体插入多态性的遗传分化及其与农艺性状的关联。

背景技术由于蜡质玉米被认为是韩国的主要经济作物，因此了解其遗传变异和分化是选择性植物育种的基础。玉米基因组主要由转座因子组成，为此，大而稳定的插入会产生反映进化过程中选择的变异。目的本研究旨在阐明基于TEs贡献的遗传多样性，并研究Mu转座对蜡质和普通玉米遗传差异的影响。我们还对这些自交系进行了关联分析，以确定与农艺性状相关的Mu插入。方法在这项研究中 我们利用基于突变子的转座子展示方法研究了玉米研究所江原农业研究与推广服务中心收集的40个糯性和40个普通自交系玉米的遗传多样性和种群结构。结果我们检测到278个Mut（Mu）锚定基因座中86.33％的多态性，反映了Mu元素的活性及其对遗传变异的贡献。普通玉米显示出大量的遗传多样性，这比蜡质玉米所观察到的更大。主坐标和邻域聚类分析始终支持两个遗传上不同的群体的存在。然而，种群内遗传变异的分布远高于种群间的遗传分化。为了探索Mu元素对表型变异的贡献，我们分析了与10个重要农艺性状的关联。基于两个模型（QGLM和Q + KLM）的组合结果，我们发现七个Mu基因座和四个不同性状之间存在显着关联。结论这些结果将有助于糯玉米育种者选择亲本系，并有助于标记辅助选择。