Xie Shanggeng, Wang Fengyue, Li Mengdi, Hu Zengjie, Wang Han, Zhang Zhizhong, Chen Xiang, Gu Zhiye, Zhang Guoping, Ye Lingzhen
Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
Zhongyuan Institute, Zhejiang University, Zhengzhou, 450000, China.
Plant J. 2024 Jul;119(2):814-827. doi: 10.1111/tpj.16798. Epub 2024 May 13.
Several dwarf and semi-dwarf genes have been identified in barley. However, only a limited number have been effectively utilized in breeding programs to cultivate lodging resistant varieties. This is due to the common association of dwarf and semi-dwarf traits with negative effects on malt quality. In this study, we employed gene editing to generate three new haplotypes of sdw1/denso candidate gene gibberellin (GA) 20-oxidase2 (GA20ox2). These haplotypes induced a dwarfing phenotype and enhancing yield potential, and promoting seed dormancy, thereby reducing pre-harvest sprouting. Moreover, β-amylase activity in the grains of the mutant lines was significantly increased, which is beneficial for malt quality. The haplotype analysis revealed significant genetic divergence of this gene during barley domestication and selection. A novel allele (sdw1.ZU9), containing a 96-bp fragment in the promoter region of HvGA20ox2, was discovered and primarily observed in East Asian and Russian barley varieties. The 96-bp fragment was associated with lower gene expression, leading to lower plant height but higher germination rate. In conclusion, HvGA20ox2 can be potentially used to develop semi-dwarf barley cultivars with high yield and improved malt quality.
在大麦中已鉴定出多个矮秆和半矮秆基因。然而，在培育抗倒伏品种的育种计划中，只有少数基因得到了有效利用。这是因为矮秆和半矮秆性状通常与对麦芽品质的负面影响相关联。在本研究中，我们利用基因编辑技术产生了sdw1/denso候选基因赤霉素（GA）20-氧化酶2（GA20ox2）的三种新单倍型。这些单倍型诱导了矮化表型，提高了产量潜力，并促进了种子休眠，从而减少了收获前的发芽。此外，突变系籽粒中的β-淀粉酶活性显著增加，这有利于麦芽品质。单倍型分析揭示了该基因在大麦驯化和选择过程中的显著遗传分化。发现了一个新的等位基因（sdw1.ZU9），它在HvGA20ox2启动子区域含有一个96bp的片段，主要在东亚和俄罗斯大麦品种中观察到。这个96bp的片段与较低的基因表达相关，导致植株较矮但发芽率较高。总之，HvGA20ox2有潜力用于培育高产且麦芽品质改良的半矮秆大麦品种。
