Drought tolerance of plants is related to their root system architecture. The architecture of a mature plant root system is closely linked to seminal root growth at the seedling stage; hence, selection for root characteristics at the seedling stage may identify genotypes better suited for drought conditions. Here, the genetics of seminal root angle and number were investigated in three doubled haploid mapping populations of wheat. All populations showed significant phenotypic variation for both traits and each demonstrated transgressive segregation. In total, 34 genomic regions were associated with seminal root traits; however, most QTLs were variable from year to year and were population specific. Considering only the results consistent across both years of experiments, five QTLs for seminal root angle were identified on chromosomes 2DS, 5BS, 6AL, 7A, and 7BS, but only the 2DS QTL appeared in two of the three populations. For the seminal root number, one QTL was identified on 4BL. Correlation analyses for seminal root angle, number, and seed weight revealed interesting relationships to consider for future research. In one population, those interactions wrongfully identified QTLs for seed weight as QTLs for seminal root traits. Our findings demonstrate that seminal root angle and number are complex traits and despite high heritability, may be more difficult to unwind than previously proposed.

中文翻译：

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具有共同亲本的三种面包小麦（Triticum aestivum L.）群体中与精根角和数量相关的数量性状位点（QTL）的遗传定位

植物的耐旱性与其根系结构有关。成熟植物根系的结构与幼苗期的精根生长密切相关；因此，在幼苗阶段选择根系特征可以确定更适合干旱条件的基因型。在这里，在小麦的三个双单倍体作图群体中研究了精根角度和数量的遗传学。所有种群都显示出两种性状的显着表型变异，并且每个种群都表现出海侵分离。总共有 34 个基因组区域与精根性状相关；然而，大多数 QTL 每年都在变化，并且是群体特异性的。仅考虑两年实验结果一致，在染色体 2DS、5BS、6AL、7A 和 7BS，但只有 2DS QTL 出现在三个群体中的两个群体中。对于精根数，在4BL上鉴定出1个QTL。对精根角度、数量和种子重量的相关分析揭示了未来研究中需要考虑的有趣关系。在一个群体中，这些相互作用错误地将种子重量的 QTL 识别为精根性状的 QTL。我们的研究结果表明，精根角度和数量是复杂的特征，尽管具有很高的遗传性，但可能比之前提出的更难以展开。这些相互作用错误地将种子重量的 QTL 识别为精根性状的 QTL。我们的研究结果表明，精根角度和数量是复杂的特征，尽管具有很高的遗传性，但可能比之前提出的更难以展开。这些相互作用错误地将种子重量的 QTL 识别为精根性状的 QTL。我们的研究结果表明，精根角度和数量是复杂的特征，尽管具有很高的遗传性，但可能比之前提出的更难以展开。