He Niqing, Zhan Guanping, Huang Fenghuang, Abou-Elwafa Salah Fatouh, Yang Dewei
Rice Research Institute, Fujian High Quality Rice Research and Development Center, Fujian Academy of Agricultural Sciences, Fuzhou, China.
College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China.
Front Plant Sci. 2022 May 27;13:878558. doi: 10.3389/fpls.2022.878558. eCollection 2022.
Plant height is one of the most important agronomical traits in rice ( L.). Introducing the rice in the 1960s significantly enhanced the rice yield potential in Asia. Implementing near-isogenic lines (NILs) is the most powerful tool for the identification and fine mapping of quantitative trait loci (QTLs). In this study, 176 NILs were produced from the crossing and back-crossing of two rice cultivars. Specifically, the rice cultivar Jiafuzhan served as a recipient, and the restorer cultivar Hui1586 served as a donor. Using the 176 NILs, we identified a novel major QTL for reduced plant height in the NIL36 line. The QTL was mapped to a 31 kb genomic region between the indel markers and . The rice genome annotation indicated the presence of three candidate genes in this genomic region. Through gene prediction and cDNA sequencing, we confirmed that () is the target gene in the NIL36 line. Further analysis showed that the QTL is caused by a 1 bp deletion in the first exon that resulted in premature termination of the . Knockout experiments showed that the QTL is responsible for the reduced plant height phenotype of the NIL36 line. Although the gene from the NIL36 line showed a shorter panicle length, fewer spikelets per panicle and a lower plant grain yield, the plant also exhibited a lower plant height. Taken together, our results revealed that the have good specific application prospects in future rice breeding.
株高是水稻（Oryza sativa L.）最重要的农艺性状之一。20世纪60年代引入的矮秆水稻显著提高了亚洲的水稻产量潜力。构建近等基因系（NILs）是鉴定和精细定位数量性状基因座（QTLs）最有效的工具。在本研究中，通过两个水稻品种的杂交和回交产生了176个NILs。具体而言，粳稻品种嘉辐占作为受体，恢复系品种惠1586作为供体。利用这176个NILs，我们在NIL36株系中鉴定出一个控制株高降低的新的主效QTL。该QTL被定位在插入缺失标记RM12881和RM12884之间31 kb的基因组区域。水稻基因组注释表明该基因组区域存在三个候选基因。通过基因预测和cDNA测序，我们证实LOC_Os02g44780（D3）是NIL36株系中的目标基因。进一步分析表明，该QTL是由第一个外显子中的1个碱基缺失导致D3提前终止引起的。基因敲除实验表明，该QTL导致了NIL36株系的株高降低表型。虽然来自NIL36株系的D3基因表现出较短的穗长、每穗较少的小穗数和较低的单株籽粒产量，但该植株也表现出较低的株高。综上所述，我们的结果表明D3在未来水稻育种中具有良好的具体应用前景。
