文献类型： 外文期刊

作者： Xie, Jianyin ¹ ; Wang, Weiping ² ; Yang, Tao ¹ ; Zhang, Quan ¹ ; Zhang, Zhifang ¹ ; Zhu, Xiaoyang ¹ ; Li, Ni ² ; Zhi, Linran ¹ ; Ma, Xiaoqian ¹ ; Zhang, Shuyang ¹ ; Liu, Yan ¹ ; Wang, Xueqiang ¹ ; Li, Fengmei ¹ ; Zhao, Yan ¹ ; Jia, Xuewei ¹ ; Zhou, Jieyu ¹ ; Jiang, Ningjia ¹ ; Li, Gangling ¹ ; Liu, Miaosong ¹ ; Liu, Shijin ¹ ; Li, Lin ¹ ; Zeng, An ¹ ; Du, Mengke ¹ ; Zhang, Zhanying ¹ ; Li, Jinjie ¹ ; Zhang, Ziding ¹ ; Li, Zichao ¹ ; Zhang, Hongliang ¹ ;

作者机构： 1.China Agr Univ, Lab Crop Heterosis & Utilizat, Minist Educ, Beijing Key Lab Crop Genet Improvement, Beijing 100193, Peoples R China

2.Hunan Hybrid Rice Res Ctr, State Key Lab Hybrid Rice, Changsha 410125, Peoples R China

3.Hainan Univ, Sanya Nanfan Res Inst, Sanya 572024, Peoples R China

4.China Agr Univ, Sanya Inst, Sanya 572024, Peoples R China

5.China Agr Univ, State Key Lab Agrobiotechnol, Beijing 100193, Peoples R China

关键词： Hybrid rice; Heterosis; Nonadditive; HoIIB model

期刊名称：GENOME BIOLOGY （ 影响因子：12.3； 五年影响因子：17.4 ）

ISSN： 1474-760X

年卷期： 2022 年 23 卷 1 期

页码：

收录情况： SCI

摘要： Background: Heterosis is widely used in agriculture. However, its molecular mechanisms are still unclear in plants. Here, we develop, sequence, and record the phenotypes of 418 hybrids from crosses between two testers and 265 rice varieties from a mini-core collection. Results: Phenotypic analysis shows that heterosis is dependent on genetic backgrounds and environments. By genome-wide association study of 418 hybrids and their parents, we find that nonadditive QTLs are the main genetic contributors to heterosis. We show that nonadditive QTLs are more sensitive to the genetic background and environment than additive ones. Further simulations and experimental analysis support a novel mechanism, homo-insufficiency under insufficient background (HoIIB), underlying heterosis. We propose heterosis in most cases is not due to heterozygote advantage but homozygote disadvantage under the insufficient genetic background. Conclusion: The HoIIB model elucidates that genetic background insufficiency is the intrinsic mechanism of background dependence, and also the core mechanism of nonadditive effects and heterosis. This model can explain most known hypotheses and phenomena about heterosis, and thus provides a novel theory for hybrid rice breeding in future.