胡杨幼苗生长相关性状QTL上位性分析  

QTL epistasis effect analysis of seedling growth-related traits in Populus euphratica

作　　者：王平 王东洋 王晶 姜立波 邬荣领 Wang Ping;Wang Dongyang;Wang Jing;Jiang Libo;Wu Rongling(Center of Computational Biology,College of Biological Sciences and Biotechnology,Beijing Forestry University, Beijing 100083,China)

机构地区：[1]北京林业大学生物科学与技术学院,计算生物学中心,北京100083

出　　处：《北京林业大学学报》2018年第12期49-59,共11页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31700576);国家林业公益性行业科研专项(201404102).

摘　　要：【目的】幼苗期是植物生长发育的重要阶段,幼苗生长相关性状的研究对改善农作物以及林木的生产以及提高抗逆性具有重要意义。目前尚无研究对胡杨幼苗生长阶段相关表型的上位互作机制进行解析。【方法】本研究以包含408个单株的胡杨×胡杨杂交的F1代群体为实验材料,获取茎高、主根长、总侧根长和侧根数量4种表型动态生长数据;基于该群体所构建的高密度连锁图谱,通过功能作图和2HIGWAS对基因之间的上位互作进行定位。【结果】共侦测出QTL-QTL互作83对,包含83个SNPs。其中主根长、茎高、侧根总长、侧根数量分别检验出24对、20对、24对、15对显著QTL互作;主根长、茎高以及侧根总长较大比例的上位互作分别集中分布于连锁群1、19和17。另外对4个表型显著上位互作的QTLs进行功能注释,19个QTLs注释到候选基因。【结论】影响侧根总长的显著互作具有较高的遗传力,在连锁群17集中分布,可能是重要的候选基因区域,能够为胡杨以及林木分子标记辅助育种提供重要的借鉴。[Objective] Seedling stage plays a vital role in plant growth and development. Up to date there are no reports about genetic mechanism of epistasis interaction during seedling growth in Populus euphratica.[Method] In this study, a full-sib F1 population including 408 individuals was derived from Populus euphratica × Populus euphratica. Dynamic growth data of four phenotypes were measured, including the taproot length, shoot length, total lateral root length, and number of lateral roots. Based on a high-density genetic linkage map, 2HIGWAS was employed to identify QTL-QTL interactions associated with four phenotypes. [Result] Finally, a total of 83 pairs of QTL-QTL interactions were detected, including 83 SNPs. The taproot length, shoot length, total lateral root length and number of lateral roots found 24 pairs, 20 pairs, 24 pairs and 15 pairs epistatic interactions, respectively, and the epistatic interactions of main root length, stem height and lateral root length were distributed in linkage groups 1, 19, and 17, respectively. In addition, we conducted functional annotations for the SNPs with significant QTL-QTL epistatic interactions, and 19 QTLs were annotated with candidate genes. [Conclusion] Interactions associated with total lateral root length had higher heritability, and most of the SNPs were located in linkage group 17, which might be important candidate gene regions. This work may provide guidance for molecular marker-assisted breeding of Populus euphratica and other forest trees.

关 键 词：QTL 上位效应 2HIGWAS 幼苗生长 胡杨 

分 类 号：S722[农业科学—林木遗传育种]