水稻杂种优势和配合力遗传基础的全基因组解析及杂种优势群的初步划分

Genetic dissection of crop heterosis and combining ability plays an vitally important role in high and stable yield breeding. In this project, we use 120 elite rice varieties that have been re-sequenced in our previous work and some varieties chose from the 3,000 rice genomes project as crossing parents. According to the NCII mating design, a large number of hybrid combinations will be obtained and further investigate their traits by multi-year and multi-site field testing. Based on GBLUP models, wide-genome prediction models and methods of parents、heterosis (cross combination phenotypes) and combining ability were established and discussed, and further are applied to combining ability analysis of rice experimental data. Genome wide association analysis (GWAS) of the genetic basis of rice yield heterosis and combining ability will be carried out; Based on the cluster analysis of parental SNP markers and hybrid combinations phenotypes (heterosis values, special combining ability values), rice heterosis groups are preliminary divided. This project, researched from the wide-genome level, will play an important role in promoting the study of heterosis and combining ability from general genetics description stage to single effect analysis. And it can also lay the foundation for the accumulation of rice elite genes and excellent combining ability genes by molecular marker assisted selection in the future, and we will do some exploratory work for exploring a feasible route.

作物杂种优势与配合力的遗传基础剖析与预测，对其高产稳产育种至关重要。本项目提出，采用本课题组完成重测序的120个水稻品种和“3K水稻基因组项目”中的部分品种为亲本，按照NCII交配设计，大量配制杂交组合，进行多年多点田间试验；基于GBLUP模型，探讨亲本、杂种优势（杂交组合表现）和配合力的基因组预测模型与方法，并应用于水稻实验数据的分析，即进行配合力分析，进而进行水稻产量杂种优势与配合力遗传基础的全基因组关联分析；利用水稻亲本SNP标记及杂交组合表型（杂种优势值、特殊配合力值）的聚类分析，进行水稻杂种优势群的初步划分。本项目从基因组水平开展研究，对杂种优势研究和配合力研究从整体遗传学描述阶段向单个效应解析阶段的发展，具有重要的推动作用；亦可为下一步应用分子标记辅助选择累加水稻优势群内的优势基因、优异配合力基因奠定基础，并为探索出一条可行的路线做些试探性的工作。