Global warming threatens many aspects of human life, including a reduction in crop yields, and breeding heat-tolerant crops is a fundamental way to help address this challenge. As food for more than half of the global population, rice (Oryza sativa) has always been a popular research material in plant science. Breeding heat-tolerant rice using genes affording thermotolerance is a fundamental way to address this challenge. In this study, a major QTL, TT1-2, was found to regulate heat tolerance in rice; this QTL was controlled by a single dominant gene. Using F2:3 populations, we narrowed TT1-2 to a 26.0-kb region containing three putative genes, one of which encodes an α2 subunit of the 26S proteasome. This gene was considered the TT1-2 candidate, and the TT1 gene involved in rice heat tolerance was present at this locus. Further analysis showed that the amino acid sequence of the TT1-2 gene had one amino acid difference: arginine (R)-99 was changed to histidine (H), which leads to the formation of a normal alpha-helix. Moreover, through marker-assisted selection and conserved breeding selection, we developed a new male-sterile line, Zhehang 10A, which had a high outcrossing rate, good quality, and strong heat tolerance. We then used Zhehang 10A as the female parent and the restorer line Fuhui 1586 as the male parent and bred a new hybrid, Zhehangyou 1586, which showed high yield, good quality, and strong heat tolerance.

中文翻译：

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一个主要 QTL 的鉴定和精细定位，TT1-2，在调节水稻耐热性中起重要作用

全球变暖威胁着人类生活的许多方面，包括作物产量下降，而培育耐热作物是帮助应对这一挑战的基本方法。作为全球一半以上人口的食物，水稻（Oryza sativa）一直是植物科学领域的热门研究材料。使用具有耐热性的基因培育耐热水稻是应对这一挑战的基本方法。在这项研究中，发现了一个主要的 QTL TT1-2，它可以调节水稻的耐热性；该 QTL 受单个显性基因控制。使用 F2:3 种群，我们将 TT1-2 缩小到包含三个推定基因的 26.0-kb 区域，其中一个基因编码 26S 蛋白酶体的 α2 亚基。该基因被认为是 TT1-2 候选基因，在该位点存在与水稻耐热性有关的 TT1 基因。进一步分析表明，TT1-2基因的氨基酸序列有一个氨基酸差异：精氨酸(R)-99变为组氨酸(H)，导致形成正常的α-螺旋。此外，通过标记辅助选择和保守育种选择，我们培育出了异交率高、品质好、耐热性强的雄性不育新系浙航10A。以浙航10A为母本，恢复系富辉1586为父本，选育出高产、优质、耐热性强的新杂种浙航优1586。通过标记辅助选择和保守育种选择，培育出异交率高、品质好、耐热性强的雄性不育新系浙航10A。以浙航10A为母本，恢复系富辉1586为父本，选育出高产、优质、耐热性强的新杂种浙航优1586。通过标记辅助选择和保守育种选择，培育出异交率高、品质好、耐热性强的雄性不育新系浙航10A。以浙航10A为母本，恢复系富辉1586为父本，选育出高产、优质、耐热性强的新杂种浙航优1586。