玉米优良自交系‘京92’遗传重组及杂种优势解析  

Genetic Recombination Dissection and Heterosis of the Elite Maize Inbred Line‘Jing92’

作　　者：赵久然[1] 李春辉 宋伟[1] 王元东[1] 张如养[1] 王继东[1] 孙轩 王夏青 Zh ao Jiuran;Li Ch unhui;Song Wei;Wang Yuandong;Zhang Ruyang;Wang Jidong;Sun Xuan;Wang Xiaqing(Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding,Maize Research Center,Beijing Academy of Agriculture and Forestry Sciences,Beijing,100097)

机构地区：[1]北京市农林科学院玉米研究中心,玉米DNA指纹及分子育种北京市重点实验室,北京100097

出　　处：《分子植物育种》2021年第15期5172-5179,共8页Molecular Plant Breeding

基　　金：北京市农林科学院青年科研基金(QNJJ201727);北京学者计划项目(BSP041);现代农业产业技术体系专项(CARS-02-11)共同资助。

摘　　要：‘京92’骨干玉米自交系是以‘(京24’ב昌7-2’)בLx9801’构建基础选系群体,利用“高大严”等自交系选育方法创制的优良黄改群自交系。其作为父本育成的代表性品种‘京科968’,自2016年起年推广面积达1.30×106 hm2以上。本研究通过分析‘京92’形成过程中的重组事件和‘黄早四’基因组片段传递规律,解析‘京92’形成的遗传机制,以期为黄改系的进一步遗传改良提供参考。通过比较分析‘黄早四’、‘京92’及其选系亲本‘(昌7-2‘’京24’和‘Lx9801’)材料,与‘京724‘’京464’和‘京D9H’3份X群代表系所组配的F1产量相关性状,发现‘京92’比其他4份黄改系具有更高的中亲优势和超高亲优势。利用全基因组重测序技术重现了‘京92’形成过程中的重组事件,明确了‘京92’的基因组组成和重组位置,‘昌7-2’、‘京24’和‘Lx9801’在‘京92’基因组中保留的比例分别为43.34%、13.46%和43.19%。通过对基因组测序数据进行分析,解析从‘黄早四’到‘京92’的IBD(Identity-by-descent)片段,结果表明‘京92’保留的‘黄早四’片段比例为43.83%,并且从‘昌7-2’、‘京24’和‘Lx9801’三个选系亲本中聚合了9个重要黄改系IBD保守区域。优良自交系‘京92’在遗传改良过程中,通过染色体重组聚合了‘昌7-2’、‘京24’和‘Lx9801’三个选系亲本几乎所有的重要黄改系IBD保守区域,从分子水平解释了‘京92’与X群代表系组配表现出更高配合力的遗传基础。'Jing92'is one of the elite maize'Huangzaosi'-improved lines(HILs),which is bred from the population constructed using('Jing24'×'Chang7-2')×'Lx9801'according to"Gao Da Yan"theory.The representative variety'Jingke968'is bred using'Jing92'as a male parent,and the growing area of'Jingke968'is more than 1.30×106 hm2 per year since 2016.This study was to reveal recombination events during the formation of'Jing92'and the identity-by-descent(IBD)segments transferred from'Huangzaosi'genome,which can provide the genetic basis for the formation of'Jing92'and valuable guidance of the further genetic improvements of HILs.We found that'Jing92'had higher mid-parent heterosis and over-high parent heterosis than the other four HILs to compare the yield related traits in the F1 hybridized combinations which were obtained by crossing'Huangzaosi','Jing92',and its parents('Chang7-2','Jing24','Lx9801')with the three lines'Jing724','Jing464'and'JingD9H'from X group.Using whole genome resequencing,we identified the component of the genome of'Jing92'and recombination events,and found that there were 43.34%,13.46%,43.19%of the genome regions of'Jing92'from'Chang7-2','Jing24','Lx9801',respectively.We found the IBD regions from'Huangzaosi'to'Jing92',which was accounted for 43.83%,of the genome,and'Jing92'genome polymerized all nine important HILs IBD conserved regions from its three parents.The elite line'Jing92'genome polymerized nearly all important HILs IBD conserved regions from its parents'Chang7-2','Jing24'and'Lx9801'by chromosome recombination during its genetic improvement.This study revealed the molecular basis for higher combining ability of'Jing92',which crossed with the representative lines from X group.

关 键 词：‘京92’ 遗传重组 同源传递片段 杂种优势 

分 类 号：S513[农业科学—作物学]