Seed hardness trait has a profound impact on cooking time and canning quality in dry beans. This study aims to identify the unknown genetic factors and associated molecular markers to better understand and tag this trait. An F2:7 recombinant inbred line (RIL) population was derived from a cross between the hard and soft seeded black bean parents (H68-4 and BK04-001). Eighty-five RILs and the parental lines were grown at two locations in southern Manitoba during years 2014-2016. Seed samples were harvested manually at maturity to test for seed hardness traits. The hydration capacity and stone seed count were estimated by soaking the seeds overnight at room temperature following AACC method 56-35.01. Seed samples from 2016 tests were also cooked to determine effect of seed hardness on cooking quality. For mapping of genomic regions contributing to the traits, the RIL population was genotyped using the genotype by sequencing (GBS) approach. The QTL mapping revealed that in addition to the major QTL on chromosome 7 at a genomic location previously reported to affect seed-hydration, two novel QTL with significant effects were also detected on chromosomes 1 and 2. In addition, a major QTL affecting the visual appeal of cooked bean was mapped on chromosome 4. This multi-year-site study shows that despite large environmental effects, seed hardness is an oligo-genic and highly heritable trait, which is inherited independently of the cooking quality scored as visual appeal of cooked beans. The identification of the QTLs and development of SNP markers associated with seed hardness can be applied for common bean variety improvement and genetic exploitation of these traits.

中文翻译：

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黑色普通豆（Phaseolus vulgaris）重组自交系（RIL）群体种子硬度性状的遗传分析和QTL定位。

种子硬度特性对干豆的烹饪时间和罐头质量有深远的影响。这项研究旨在鉴定未知的遗传因素和相关的分子标记，以更好地理解和标记该性状。F2：7重组自交系（RIL）群体来自硬种子和软种子黑豆亲本（H68-4和BK04-001）之间的杂交。在2014-2016年间，曼尼托巴省南部的两个地方种植了85个RIL和亲本。在成熟时手动收获种子样品以测试种子硬度性状。通过根据AACC方法56-35.01在室温下将种子浸泡过夜来估计水合能力和石头种子数量。还烹饪了2016年测试的种子样品，以确定种子硬度对烹饪质量的影响。为了对有助于性状的基因组区域作图，使用测序基因型（GBS）方法对RIL群体进行基因分型。QTL作图显示，除了先前报道的影响种子水合作用的基因组位置的第7号染色体上的主要QTL之外，还在染色体1和2上检测到两个具有显着影响的新QTL。煮熟的豆的吸引力映射到第4号染色体上。这项历时数年的研究表明，尽管受到很大的环境影响，种子硬度还是一种寡聚和高度遗传的性状，其遗传性与煮熟后的视觉吸引力无关豆子。