橡胶树分枝性状的全基因组关联分析及关键候选基因鉴定

橡胶树是一种重要的热带经济林木，不仅是天然橡胶的主要来源，也是一种良好的用材林。分枝性状是典型的数量遗传性状，决定橡胶树的抗风性和木材利用率，是橡胶树育种筛选的重要指标之一。但目前橡胶树分枝性状形成的相关基因尚未被定位，育种过程中分枝性状的鉴定需要依靠成龄树进行，鉴定和选择周期较长。本项目在对农业部景洪橡胶树种质资源圃保存的2700份橡胶树1981'IRRDB种质（无性系）2014年至今性状跟踪观测的基础上，利用已获得的染色体水平的高质量橡胶树基因组图谱，通过构建初级核心种质群体、基因组重测序、SNP筛选和全基因组关联分析，对与橡胶树“侧枝粗细”和“侧枝分枝角”2个重要分枝性状相关的候选基因进行定位，利用Real-time RT-PCR对候选靶标基因进行筛选，并通过转基因烟草对筛选出的关键基因进行功能验证。本项目的实施，将为橡胶树育种材料的分子标记早期筛选提供技术支撑。

Rubber tree is an important tropical economic forest. It is not only the main source of natural rubber, but also a good timber forest. Branching traits are a typical quantitative genetic traits that determine the wind resistance and wood utilization of rubber trees, and are one of the important indicators of rubber tree breeding. However, at present, the genes related to the formation of branching traits of rubber trees have not been mapped. The identification of branching traits in the rubber tree breeding process depends on the ageing tree, which is a long cycle and very time-consuming. Based on the observation from 2014 to present of 2700 copies of 81'IRRDB germplasm (clones) which preserved in Jinghong germplasm resources nursery and the chromosome-level high-quality rubber tree genome, this project is intend to construct primary core collection. The key candidate genes related to branch diameter and branch angle of rubber trees will been identified by genomic resequencing, SNP screening, genome-wide association analysis, candidate genes mapping and key genes screening, the key genes will been screened and verified by Real-time RT-PCR and transgenic tobacco. The project will provide technical support for molecular marker-assisted early selection of branching traits of rubber tree breeding materials.