학술논문

小麦粒重相关性状的QTL定位及分子标记的开发 / QTL Mapping and Molecular Marker Development of Traits Related to Grain Weight in Wheat
Document Type
Academic Journal
Source
中国农业科学 / Scientia Agricultura Sinica. 56(21):4137-中插13
Subject
小麦
千粒重
QTL
KASP标记
分子标记辅助选择育种
wheat
thousand-grain weight
KASP marker
molecular marker-assisted selection breeding
Language
Chinese
ISSN
0578-1752
Abstract
[目的]小麦是世界总产量第二的粮食作物,而粒重是影响小麦产量的重要因素.以和尚头(HST)和陇春23(LC23)衍生的 216 个家系重组自交系(recombinant inbred lines,RIL)群体为材料,基于 55K SNP基因型数据,针对小麦粒重相关性状进行QTL定位,开发和验证粒长主效QTL的共分离标记,为分子标记辅助选择育种提供参考.[方法]利用小麦55K SNP芯片对亲本和RIL群体进行基因分型,构建高密度遗传连锁图谱,并与中国春参考基因组IWGSC RefSeq v1.0进行相关性分析.基于完备区间作图法对多环境粒重相关性状进行QTL定位;通过对主效QTL进行方差分析,判断不同QTL间的加性互作效应,并分析其对粒重相关性状的影响.同时,根据粒长主效QTL的共分离SNP位点开发相应的竞争性等位基因特异性PCR标记(kompetitive allele specific PCR,KASP),并在 242 份国内外小麦种质构成的自然群体中进行验证.[结果]构建了和尚头/陇春 23 RIL群体的高密度遗传图谱,全长 4 543 cM,共包含 22 个连锁群,覆盖小麦 21 条染色体,平均遗传距离为 1.7 cM.遗传图谱与物理图谱具有显著相关性,Pearson相关系数为 0.77-0.99(P<0.001).共检测到 51 个粒重相关QTL,其中,有 4 个为 3 个及以上环境稳定表达的主效QTL,分布在 2D、5A、6B和 7D染色体.根据物理区间和功能标记分析主效QTL Qtkw.nwafu-2D.1和Qtkw.nwafu-7D分别为光周期基因Ppd-D1和开花基因FT-D1,方差分析表明,二者具有显著的互作效应;Qtkw.nwafu-2D.1和Qtkw.nwafu-7D优异等位基因的聚合显著提高了小麦的千粒重和粒宽.此外,根据粒长主效位点Qgl.nwafu-5A的共分离SNP开发了相应的KASP分子标记AX-111067709,该标记在 242 份小麦组成的自然群体中与粒长和粒重性状显著相关,在不同环境下能增加粒长3.33%—4.59%(P<0.001)和粒重5.70%—10.35%(P<0.05).[结论]和尚头(HST)和陇春23(LC23)的粒重相关性状由多个遗传位点控制,其中,Qtkw.nwafu-2D.1和Qtkw.nwafu-7D通过加性互作效应可显著提高小麦的千粒重和粒宽.Qgl.nwafu-5A与粒重和粒长具有显著相关性,其共分离分子标记AX-11106770可应用于分子标记辅助选择育种.
[Objective]The yield of wheat,the second-highest-yielding food product in the world,has a major impact by grain weight.This research used materials from a recombinant inbred line(RIL)population derived from Heshangtou(HST)and Longchun 23(LC23).Based on 55K SNP genotype data,QTL mapping was performed for traits related to grain weight of wheat,and co-segregation markers of major grain length QTL were developed and verified to provide reference for molecular marker assisted selection breeding.[Method]The wheat 55K SNP microarray was used to genotype parents and RIL populations,and a high density genetic linkage map was constructed,and its correlation with Chinese spring reference genome IWGSC RefSeq v1.0 was analyzed.QTL mapping of traits related to grain weight in multiple environments based on inclusive composite interval mapping method.The analysis of variance of major effect QTLs were performed to judge the additive interaction effect among different QTLs,and to analyse its effect on traits related to grain weight.At the same time,the corresponding kompetitive allele specific PCR marker was developed according to the closely linked SNP loci of major QTL for grain length,and verified in 242 wheat accessions worldwide.[Result]In this study,a high density genetic map of Heshangtou/Longchun 23 RIL population was constructed,with full length 4 543 cM,including 22 linkage groups,covering 21 chromosomes of wheat,and the average genetic distance was 1.7 cM.There was a significant correlation between genetic map and physical map,and the Pearson correlation coefficient were 0.77-0.99(P<0.001).A total of 51 QTLs related to grain weight were detected,among them,4 stable major QTLs were found in multi-environments(three or more environments)and distributed on 2D,5A,6B and 7D chromosomes.According to the physical interval and functional markers,it is inferred that stable major QTLs Qtkw.nwafu-2D.1 and Qtkw.nwafu-7D are photoperiod gene Ppd-D1 and flowering gene FT-D1,respectively.The analysis of variance shows that there is a significant interaction between them.The favorite alleles polymerization of Qtkw.nwafu-2D.1 and Qtkw.nwafu-7D can significantly increase thousand grain weight and grain width of wheat.In addition,the corresponding KASP molecular detection marker AX-111067709 was developed based on the co-segregated SNP of the major locus Qgl.nwafu-5A for grain length,which was significantly correlated with grain length and grain weight traits in a diversity panel comprising of 242 wheat accessions,and could increase grain length by 3.33%to 4.59%and grain weight 5.70%to 10.35%in different environments(P<0.001).[Conclusion]There are several genetic loci that affect traits linked to grain weight in Heshangtou(HST)and Longchun 23(LC23),and Qtkw.nwafu-2D.1 and Qtkw.nwafu-7D dramatically increased thousand grain weight and grain width through additive interaction effects.Qgl.nwafu-5A is significantly correlated with grain weight and grain length,and its co-segregated molecular marker AX-11106770 can be used in molecular marker assisted selection breeding.