Abstract Grain hardness is an important factor for wheat breeding. Generally, the grain hardness of hexaploid wheat is determined by two puroindoline (PIN) genes, Pina-D1 and Pinb-D1, at the Hardness locus on chromosome 5D. Here, the grain hardness of 55 synthetic wheat lines from crosses between a durum wheat cultivar and 55 Ae. tauschii accessions were examined, and nucleotide sequence variation in Pina-Dtau1 and Pinb-Dtau1 was analyzed using the Ae. tauschii accessions. Most synthetic wheat lines showed a soft texture with smoothly rounded starch granules, whereas one exceptional line exhibited a hard texture with starch granules that tightly adhered to the matrix proteins and reduced PINA and PINB protein accumulation. The parental Ae. tauschii accession of the hard-textured synthetic line has smoothly rounded starch granules and abundant PIN accumulation in the endosperm. Any genetic change that occurred at the Pin loci was transmitted from the parental Ae. tauschii accession, but the Pina and Pinb transcription was decreased in the hard-textured synthetic line. Therefore, any genetic and/or epigenetic modification in the process of allopolyploidization might have affected the PIN accumulation in synthetic hexaploid wheat lines.

中文翻译：

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鉴定合成异源六倍体小麦的硬核质地系，减少了 Aegilops tauschii D 基因组上嘌呤二氢吲哚的积累

摘要 谷物硬度是小麦育种的重要因素。通常，六倍体小麦的籽粒硬度由位于染色体 5D 硬度位点的两个嘌呤二氢吲哚 (PIN) 基因 Pina-D1 和 Pinb-D1 决定。在这里，来自硬粒小麦品种和 55 Ae 之间杂交的 55 个合成小麦品系的谷物硬度。检查了 tauschii 种质，并使用 Ae 分析了 Pina-Dtau1 和 Pinb-Dtau1 中的核苷酸序列变异。tauschii 种质。大多数合成小麦品系质地柔软，淀粉颗粒光滑圆润，而一个特殊品系质地坚硬，淀粉颗粒紧密粘附在基质蛋白上，减少了 PINA 和 PINB 蛋白的积累。父母 Ae。硬质合成品系的 tauschii 加入具有平滑圆形的淀粉颗粒和胚乳中丰富的 PIN 积累。在 Pin 基因座发生的任何遗传变化都是从亲本 Ae 传播的。tauschii 加入，但在硬质合成品系中 Pina 和 Pinb 转录减少。因此，异源多倍化过程中的任何遗传和/或表观遗传修饰都可能影响合成六倍体小麦品系中的 PIN 积累。