Ouyang Xiang, Chang Shuoqi, Ma Xiaoling
State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Hunan Academy of Agricultural Sciences, Changsha, China.
Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of the Ministry of Education, Central South University of Forestry and Technology, Changsha, China.
Front Plant Sci. 2024 Dec 2;15:1505679. doi: 10.3389/fpls.2024.1505679. eCollection 2024.
() is one of the key genes in regulating photosynthesis and plant architecture. As the antagonistic effects of have concurrent impacts on photosynthesis and yield component traits, how we can effectively utilize the gene to further increase rice yield is not clear. In this study, we used two different main functional alleles, each of which has previously been proven to have specifically advantageous traits, and tested whether the combined alleles have a higher yield than the homozygous alleles. Our results exhibited that the combined alleles had better parent heterosis (BPH) for panicle number and the total filled grain number per plant, and had middle parent heterosis (MPH) for spikelet number per panicle without affecting thousand-grain weight when compared with the homozygous alleles. In consequence, the hybrid plants displayed highly increased grain yield compared with both homozygous parents. The hybrid plants also had better plant architecture and higher canopy photosynthesis. Western blot and proteomics results showed the hybrid plants had a middle abundant NAL1 protein level, and the upregulated proteins were mainly involved in the nucleus and DNA binding process but the downregulated proteins were mainly involved in the oxidation-reduction process, single-organism metabolic process, and fatty acid biosynthetic process. Furthermore, the hybrid vigor effect of was confirmed by substituting the mutual male parent 9311 with 9311-NIL in two super hybrid rice varieties (LYP9 and YLY1). This study demonstrates that we can achieve a higher level of grain production in hybrid rice by using the heterosis of .
（）是调节光合作用和株型的关键基因之一。由于（）的拮抗作用对光合作用和产量构成性状有同时影响，如何有效利用（）基因进一步提高水稻产量尚不清楚。在本研究中，我们使用了两个不同的主要功能（）等位基因，每个等位基因先前已被证明具有特定的优势性状，并测试了组合的（）等位基因是否比纯合等位基因具有更高的产量。我们的结果表明，与纯合等位基因相比，组合的（）等位基因在穗数和单株总实粒数上具有更好的亲本杂种优势（BPH），在每穗小穗数上具有中亲杂种优势（MPH），且不影响千粒重。因此，（）杂交植株与两个纯合亲本相比，籽粒产量大幅提高。杂交植株还具有更好的株型和更高的冠层光合作用。蛋白质免疫印迹和蛋白质组学结果表明，杂交植株的NAL1蛋白水平中等丰富，上调的蛋白质主要参与细胞核和DNA结合过程，而下调的蛋白质主要参与氧化还原过程、单细胞代谢过程和脂肪酸生物合成过程。此外，通过在两个超级杂交水稻品种（LYP9和YLY1）中用9311-NIL替代共同父本9311，证实了（）的杂种优势效应。本研究表明，利用（）的杂种优势可以在杂交水稻中实现更高水平的粮食产量。
