Wheat Landrace Genome Diversity.
Wheat Landrace Genome Diversity.
复制标题
DOI：
10.1534/genetics.116.194688
复制
发表时间：
2017-04
期刊：
影响因子：
3.3
通讯作者：
Griffiths S
中科院分区：
文献类型：
--
作者：
Wingen LU;West C;Leverington-Waite M;Collier S;Orford S;Goram R;Yang CY;King J;Allen AM;Burridge A;Edwards KJ;Griffiths S
了解面包小麦的基因组复杂性对于解开驯化过程，环境适应和未来的生物学都很重要。小麦基因组复杂性的研究进展是揭开驯化过程和驯化小麦对地球仪各种环境的适应过程的基石。此外，它对作物的未来改良非常重要，特别是在气候变化的情况下。着眼于驯化后的适应，巢式关联映射（NAM）面板60分离双亲群体的开发，主要涉及地方品种种质资源的核心集的沃特金斯六倍体小麦收集优化的遗传多样性。现代春季优良品种“Paragon”用作共同参考亲本。遗传图谱的构建遵循相同的规则，以使它们具有可比性。基于整个NAM组中估计的126，300个交叉事件的重组，总共鉴定了1611个连锁群。构建了一张包含2498个遗传位点的遗传连锁图，命名为长白猪遗传连锁图（LRC）。这些新开发的遗传学工具被用来研究基因组流动性或刚性背后的规则，例如，通过比较标记距离和标记顺序。总体而言，标记顺序高度相关，这为面包小麦种质之间的强共线性提供了支持。然而，也发现了许多不一致的连锁群和标记距离增加的例外情况，许多标记被检测到分离失真，有时作为热点存在于不同的群体。此外，在至少36个图谱中发现了易位的证据，这些易位一般属于许多不同的易位类，但在一些种质中发现了少数易位类，最常见的是众所周知的T5B：7B易位。重组率是植物育种的一个重要性状，利用交叉数作为性状进行QTL分析，确定了与重组率相关的基因座。总共检测到114个显著QTL，其中近一半来自非参考亲本。
Understanding the genomic complexity of bread wheat is important for unraveling domestication processes, environmental adaptation, and for future of... Understanding the genomic complexity of bread wheat (Triticum aestivum L.) is a cornerstone in the quest to unravel the processes of domestication and the following adaptation of domesticated wheat to a wide variety of environments across the globe. Additionally, it is of importance for future improvement of the crop, particularly in the light of climate change. Focusing on the adaptation after domestication, a nested association mapping (NAM) panel of 60 segregating biparental populations was developed, mainly involving landrace accessions from the core set of the Watkins hexaploid wheat collection optimized for genetic diversity. A modern spring elite variety, “Paragon,” was used as common reference parent. Genetic maps were constructed following identical rules to make them comparable. In total, 1611 linkage groups were identified, based on recombination from an estimated 126,300 crossover events over the whole NAM panel. A consensus map, named landrace consensus map (LRC), was constructed and contained 2498 genetic loci. These newly developed genetics tools were used to investigate the rules underlying genome fluidity or rigidity, e.g., by comparing marker distances and marker orders. In general, marker order was highly correlated, which provides support for strong synteny between bread wheat accessions. However, many exceptional cases of incongruent linkage groups and increased marker distances were also found. Segregation distortion was detected for many markers, sometimes as hot spots present in different populations. Furthermore, evidence for translocations in at least 36 of the maps was found. These translocations fell, in general, into many different translocation classes, but a few translocation classes were found in several accessions, the most frequent one being the well-known T5B:7B translocation. Loci involved in recombination rate, which is an interesting trait for plant breeding, were identified by QTL analyses using the crossover counts as a trait. In total, 114 significant QTL were detected, nearly half of them with increasing effect from the nonreference parents.