渗入杂交与小麦杂种优势  

Introgressive hybridization and wheat heterosis

作　　者：郝明[1] 张连全[1] 黄林[1] 甯顺腙[1] 袁中伟[1] 姜博 颜泽洪[1] 伍碧华[1] 郑有良[1] 刘登才[1] Ming Hao;Lianquan Zhang;Lin Huang;Shunzong Ning;Zhongwei Yuan;Bo Jiang;Zehong Yan;Bihua Wu;Youliang Zheng;Dengcai Liu(State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China,Triticeae Research Institute of Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川农业大学小麦研究所,省部共建西南作物基因资源发掘与利用国家重点实验室,成都611130

出　　处：《科学通报》2022年第26期3165-3174,共10页Chinese Science Bulletin

基　　金：国家自然科学基金(91935303);国家重点研发计划(2016YFD0102000);四川省育种攻关项目(2021YFYZ0002);四川省麦类产业技术体系(2019-2023)资助。

摘　　要：杂种优势利用是实现小麦增产稳产的重要途径.渗入杂交为小麦杂种优势利用提供了发展动力.小麦具有大量可渗入利用的近缘属种,同时基因组结构有利于外源基因渗入.目前常用的基因渗入有两种方式.一是借助染色体工程,通过不同基因组之间的部分同源染色体重组,将单个外源染色体区段以易位系为载体的方式渗入.易位系在引入外源染色体区段的同时,丢失了对应的小麦染色体区段,因此在常规育种中应用受限.但当其应用于杂交小麦,既保留了外源区段的优良基因,也不存在小麦基因缺失问题.二是通过同源染色体遗传重组,将不同染色体区段上的基因同时渗入,可实现小麦基因组遗传结构的重塑.小麦基因组缓冲性强,单个基因拷贝变化常常仅有较小的遗传效应,但多个基因的同时导入可能产生明显效果.因此,从基因组的角度丰富小麦遗传变异对杂种优势利用尤为重要.小麦3个亚基因组的遗传多样性不对称,其中D基因组的遗传多样性远低于A和B.因此,将未参与小麦进化的节节麦亚种的遗传多样性导入小麦,尽快丰富小麦D基因组的遗传多样性,是当前同源渗入的优先任务.To continue feeding the increasing global population,the amount of wheat produced in the next 50 years will need to exceed the total amount of wheat produced over the past 10000 years.This challenge is coupled with a shrinking resource base and the likely onset of climate change.Moreover,a wheat yield plateau seems to have been reached in many regions,leading to concerns that the increasing global demand will not be met without breeding innovations.Heterosis may be exploited to enhance and stabilize wheat yields,but the commercial application of hybrid wheat has been limited by the low level of heterosis.Although the genetic mechanism underlying wheat heterosis is still uncharacterized,strong heterosis is often related to the high genetic diversity of the parents.Introgressive hybridization is a powerful method for expanding the germplasm base by transferring alien genes into wheat populations,with considerable implications for advancing wheat heterosis.In addition to increasing genetic diversity,introgressed alien genes may exhibit distinct spatiotemporal expression patterns or regulatory characteristics in the receptor genetic background,which may affect heterosis.Wheat has rich wild relatives and an allohexaploid genome structure,which is conducive to gene introgression.Generally,there are two ways to introgress alien genes.First,individual chromosomal segments may be introgressed through homoeologous recombination to generate translocations that are mediated by chromosome engineering.The resulting translocations have limited use in classical wheat breeding because the introgression is accompanied by the loss of the corresponding wheat chromosomal region.However,the introgression may be beneficial for the application of heterosis because it and the corresponding wheat chromosome are maintained.Second,homologous-directed recombination enables the simultaneous introgression of multiple chromosomal regions to substantially reshape the wheat genome structure.The triplication of many genes in wheat(i.e.,three homeo

关 键 词：小麦 杂种优势利用 渗入杂交 染色体工程 多倍体 

分 类 号：S512.1[农业科学—作物学]