摘要
茎秆倒伏严重影响玉米产量、品质和机械化收获,是当前玉米生产和育种亟待解决的主要问题之一。加强对玉米茎秆抗倒伏性的研究,对提高品种抗倒伏能力具有重要意义。本文综述了玉米茎秆倒伏的主要影响因素及其遗传特征。茎秆倒伏与茎秆自身的强度密切相关。茎秆强度越高,抗倒伏性越强。茎秆强度受茎秆所处的发育阶段、茎秆内部结构和外部形态,及其细胞壁成分等影响。处于分生组织的茎秆细胞分裂旺盛,较易折断,而进入生殖生长后,茎秆表皮、厚壁组织增厚,维管束发育成熟,对茎秆的支撑作用增强。茎秆细胞壁的主要成分——纤维素、半纤维素、木质素、可溶性糖、无机物等均可提升茎秆强度。目前,研究者借助高通量表型平台,利用玉米连锁群体和自交系群体,采用各种定位方法,鉴定到一系列影响茎秆形态、强度、细胞壁成分的相关QTL和候选基因。研究表明,基于单倍型的QTL定位方法比基于单个SNP的定位效果好。一致性QTL分析将不同遗传群体的研究整合到一起,能够提高QTL结果的通用性。茎秆强度的遗传基础复杂,受微效多基因控制,位点间具有加性效应。茎秆成分QTL中的候选基因涉及细胞壁代谢、转录因子、蛋白激酶等。MAIZEWALL是玉米细胞壁相关基因的重要数据库。目前该数据库包含1156个玉米细胞壁生物学相关的候选基因,为该领域的深入研究提供强大的资源。已鉴定到一系列影响玉米茎秆细胞壁成分、茎秆形态和强度的基因,其功能涉及纤维素合成路径,如纤维素合成酶类、Cobra类、糖基转移酶和核糖转运蛋白类;苯丙烷路径基因,如控制bm1—bm5的相关基因;植物激素类,如赤霉素、生长素、油菜素甾醇相关基因;转录因子如NAC、MYB;miRNA(ZmmiR528)以及F-box基因(stiff1)等。今后应积极探索不同发育时期玉米茎秆倒伏的力学机制;广泛发展自然群体或育种群体进行遗传分析;采取多种定位策略,提高抗倒伏相关基因鉴定的功效;针对优良等位基因,开发各类分子标记,加强抗倒伏分子标记辅助选择。本文将为玉米茎秆抗倒伏遗传机制解析及抗倒伏玉米品种的分子育种提供参考。
Maize stalk lodging has a great adverse effect on yield,quality and mechanized harvesting,and is one of the main problems to be solved urgently in current maize production and breeding.Strengthening the research on the lodging resistance of maize stalk will have great significance for improving the lodging resistance of maize.In this paper,we summarize the main factors affecting maize stalk lodging resistance,and their genetic mechanisms.The stalk lodging resistance is closely related to the stalk strength.The greater the stalk strength,the stronger the lodging resistance.The stalk strength is affected by the developmental stage,the internal and external structures of the stalk,and the components of the stalk cell wall.The meristem zone has vigorously dividing cells and is easily broken.After entering the reproductive growth,the rind and sclerenchyma tissue of the stalk are thickened,the vascular bundles are mature,and thus the stalk strength is enhanced.The main components of the stalk cell wall,including cellulose,hemicellulose,lignin,soluble sugars,inorganic substances,can improve the strength of the stalk.To date,based on the high-throughput phenotyping platforms,various maize linkage and natural populations,and mapping methods,researchers have identified a series of QTLs and candidate genes that affect stalk morphology,strength,and cell wall components.The studies have shown that the haplotype-based mapping method is better than SNP-based mapping method.Meta-QTL analysis integrates the mapping results of different genetic populations and can improve the versatility of QTLs.The genetic basis of stalk strength is complex,which is determined by polygenes with minor effect and additive effect.Candidate genes in the QTLs involve cell wall metabolism,transcription factors,protein kinases,and so on.MAIZEWALL is an important database of genes related to maize cell wall.So far,the database contains 1156 candidate genes related to maize cell wall biology,which provides a powerful resource for research in this field.A series of genes affecting cell wall components,stalk morphology and stalk strength in maize have been identified.Their functions of these genes are related to cellulose synthesis pathways,such as genes of cellulose synthase,Cobra,glycosyltransferase and ribose transport;phenylpropane pathway genes,such as genes regulating bm1-bm5;plant hormones genes,such as genes related to gibberellin,auxin and brassinosteroid;transcription factors such as NAC,MYB;miRNA(ZmmiR528)and F-box genes(stiff1).In the future research,it is needed to explore the mechanical mechanism of stalk lodging at different developmental stages.Develop diverse natural populations and breeding materials for genetic analysis.Employ a various of mapping strategies to improve the efficiency of identification of the QTL and genes related to lodging resistance.Design various molecular markers based on the favorable alleles to improve the molecular marker assisted selection for lodging resistance.These efforts will promote the research of the genetic mechanism of stalk lodging resistance,and provide a reference for the molecular breeding of new varieties with strong lodging resistance.
作者
王夏青
宋伟
张如养
陈怡凝
孙轩
赵久然
WANG XiaQing;SONG Wei;ZHANG RuYang;CHEN YiNing;SUN Xuan;ZHAO JiuRan(Maize Research Center,Beijing Academy of Agriculture&Forestry Sciences/Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding,Beijing 100097)
出处
《中国农业科学》
CAS
CSCD
北大核心
2021年第11期2261-2272,共12页
Scientia Agricultura Sinica
基金
北京学者计划(BSP041)
北京市农林科学院基因组学育种协同创新中心建设项目(KJCX201907-2)
北京市农林科学院青年基金(QNJJ201931)。
关键词
玉米
倒伏
茎秆
细胞壁
遗传研究
maize
lodging
stalk
cell wall
genetic mechanism