Desiderio Francesca, Zarei Leila, Licciardello Stefania, Cheghamirza Kianoosh, Farshadfar Ezatollah, Virzi Nino, Sciacca Fabiola, Bagnaresi Paolo, Battaglia Raffaella, Guerra Davide, Palumbo Massimo, Cattivelli Luigi, Mazzucotelli Elisabetta
Council for Agricultural Research and Economics, Research Centre for Genomics and Bioinformatics, Fiorenzuola d'Arda, Italy.
Department of Agronomy and Plant Breeding, Razi University, Kermanshah, Iran.
Front Plant Sci. 2019 Apr 18;10:448. doi: 10.3389/fpls.2019.00448. eCollection 2019.
Kernel size and shape are important parameters determining the wheat profitability, being main determinants of yield and its technological quality. In this study, a segregating population of 118 recombinant inbred lines, derived from a cross between the Iranian durum landrace accession "Iran_249" and the Iranian durum cultivar "Zardak", was used to investigate durum wheat kernel morphology factors and their relationships with kernel weight, and to map the corresponding QTLs. A high density genetic map, based on wheat 90k iSelect Infinium SNP assay, comprising 6,195 markers, was developed and used to perform the QTL analysis for kernel length and width, traits related to kernel shape and weight, and heading date, using phenotypic data from three environments. Overall, a total of 31 different QTLs and 9 QTL interactions for kernel size, and 21 different QTLs and 5 QTL interactions for kernel shape were identified. The landrace Iran_249 contributed the allele with positive effect for most of the QTLs related to kernel length and kernel weight suggesting that the landrace might have considerable potential toward enhancing the existing gene pool for grain shape and size traits and for further yield improvement in wheat. The correlation among traits and co-localization of corresponding QTLs permitted to define 11 clusters suggesting causal relationships between simplest kernel size trait, like kernel length and width, and more complex secondary trait, like kernel shape and weight related traits. Lastly, the recent release of the reference genome sequence allowed to define the physical interval of our QTL/clusters and to hypothesize novel candidate genes inspecting the gene content of the genomic regions associated to target traits.
籽粒大小和形状是决定小麦收益的重要参数，是产量及其工艺品质的主要决定因素。在本研究中，一个由118个重组自交系组成的分离群体被用于研究硬粒小麦籽粒形态因子及其与粒重的关系，并对相应的数量性状位点（QTL）进行定位。该群体来源于伊朗硬粒小麦地方品种 “Iran_249” 与伊朗硬粒小麦品种 “Zardak” 的杂交。基于小麦90k iSelect Infinium SNP分析构建了一个包含6195个标记的高密度遗传图谱，并利用来自三个环境的表型数据，对籽粒长度和宽度、与籽粒形状和重量相关的性状以及抽穗期进行QTL分析。总体而言，共鉴定出31个不同的籽粒大小QTL和9个QTL互作，以及21个不同的籽粒形状QTL和5个QTL互作。地方品种Iran_249对大多数与籽粒长度和粒重相关的QTL贡献了具有正向效应的等位基因，这表明该地方品种在增强现有粒形和粒重性状基因库以及进一步提高小麦产量方面可能具有相当大的潜力。性状之间的相关性以及相应QTL的共定位确定了11个簇群，表明最简单的籽粒大小性状（如籽粒长度和宽度）与更复杂的二级性状（如籽粒形状和重量相关性状）之间存在因果关系。最后，最近发布的参考基因组序列使得我们能够确定QTL/簇群的物理区间，并通过检查与目标性状相关的基因组区域的基因内容来推测新的候选基因。
