中国农业科学 ›› 2023, Vol. 56 ›› Issue (10): 1838-1847.doi: 10.3864/j.issn.0578-1752.2023.10.002

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

基于分子标记技术玉米抗粗缩病种质资源的筛选与应用

王江浩(), 王立伟, 张动敏, 郭瑞, 张全国, 李兴华, 魏剑锋, 宋炜, 王宝强(), 李荣改()   

  1. 河北省农林科学院粮油作物研究所/河北省作物遗传育种实验室,石家庄 050035
  • 收稿日期:2022-12-17 接受日期:2023-02-13 出版日期:2023-05-16 发布日期:2023-05-17
  • 通信作者: 王宝强,E-mail:wbq662@126.com。李荣改,E-mail:lironggai@haafs.org
  • 联系方式: 王江浩,E-mail:wangjianghao@haafs.org。
  • 基金资助:
    河北省重点研发计划(22326317D); 河北省农林科学院创新工程人才专项(C22R0302); 河北省重大专项(21326319D); 国家玉米产业技术体系专项(CARS-02-58)

Molecular Marker Assisted Identification and Application of Maize Germplasms for Maize Rough Dwarf Disease Resistance

WANG JiangHao(), WANG LiWei, ZHANG DongMin, GUO Rui, ZHANG QuanGuo, LI XingHua, WEI JianFeng, SONG Wei, WANG BaoQiang(), LI RongGai()   

  1. Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences/Hebei Laboratory of Crop Genetics and Breeding, Shijiazhuang 050035
  • Received:2022-12-17 Accepted:2023-02-13 Published:2023-05-16 Online:2023-05-17

摘要:

【目的】利用与3个玉米抗粗缩病位点qMrdd2Rmrdd6qMrdd8紧密连锁的分子标记筛选高抗玉米粗缩病自交系,并进行杂种优势类群分类和配合力分析,为玉米抗粗缩病品种的快速高效选育提供依据和方法。【方法】将抗病自交系K36与感病自交系S221杂交,从F2开始,采用单粒传的方法构建一个包括263个F9家系的重组自交系(recombinant inbred lines,RILs)群体;在不同种植环境下,对RILs进行抗病性鉴定,同时,采用与3个抗病位点qMrdd2Rmrdd6qMrdd8紧密连锁的分子标记5FR、6W53和IDP25K进行基因型分型,筛选出抗病且农艺性状优良家系;利用Maize56K SNP芯片对包括优良家系在内的24份玉米自交系进行基因型分型,根据Roger’s算法计算优良家系与其他骨干自交系之间的遗传距离,并在构建聚类图的基础上进行杂种优势类群划分;同时利用优良家系与不同类群的自交系测交配制杂交组合,在田间进行配合力测定和抗病性鉴定,筛选出抗病且杂种优势强的组合。【结果】自交系K36在qMrdd2Rmrdd6qMrdd8等3个抗性位点处均为抗病性纯合基因型,自交系S221均为感病性纯合基因型。RILs群体的263个家系在粗缩病抗性遗传组成上分为21种基因型,3个位点均为抗性纯合基因型家系的病情指数(DSI)最小(0.281),均为感病性纯合基因型家系的DSI最大(0.776),这与抗、感性亲本的DSI表现一致(0.257和0.623);2个位点为感病性纯合基因型时,1个位点为抗病性纯合基因型的DSI由小到大的位点是Rmrdd6(0.396)、qMrdd8(0.478)和qMrdd2(0.654),结果表明,Rmrdd6抗病性最强,qMrdd8次之,qMrdd2最弱。筛选出的3个抗性位点纯合基因型家系JR2136与其他23份自交系的遗传距离变化范围为0.2234—0.2895,平均值为0.2612,与之遗传距离最小的自交系是C413,最大的是Chang7-2。根据聚类分析结果,将JR2136划分在瑞德群,与属于黄改群的自交系H92和H521配制出抗病强的优势组合,分别比郑单958增产7.01%和7.80%,表明JR2136与属于黄改群的自交系之间具有良好的配合力。【结论】玉米自交系K36对粗缩病的抗性由qMrdd2Rmrdd6qMrdd8等3个基因控制、呈数量遗传特征且具有基因累加效应,具有3个抗性纯合基因型的玉米品种抗病性最强。开发的与3个位点紧密连锁的分子标记在抗病品种选育和抗性种质资源筛选上具有实用价值,利用分子标记进行辅助选择和基因聚合的方法选育抗病性强的优势组合应用于生产切实可行。

关键词: 玉米粗缩病, 抗病基因, 分子标记辅助选择, 优势类群划分, 配合力

Abstract:

【Objective】Molecular markers tightly linked to three maize rough dwarf disease (MRDD) resistant loci were employed to identify resistant inbred lines, then the classification of heterotic groups and analysis of combining ability of these inbred lines were carried out, which proved a highly efficient way for maize MRDD resistance breeding.【Method】A recombinant inbred lines (RILs) population consisting of 263 F9 lines was developed through single seed descent method from a segregating F2 population by crossing a resistant inbred line K36 to a susceptible inbred line S221. The MRDD resistances of the RILs were identified in different growing environments. Meanwhile the RILs were genotyped by employing three pairs of molecular markers, 5FR, 6W53 and IDP25K which were closely linked to the three resistant loci, qMrdd2, Rmrdd6 and qMrdd8. The excellent lines with disease resistance and good agronomic traits were selected out after field evaluation. Totally 24 maize inbred lines including the elite lines were genotyped using Maize 56K SNP array, then the genetic distances between the selected lines and other elite inbred lines were calculated according to Roger's algorithm and cluster analysis was conducted to classify the heterotic groups. Meanwhile, hybrid combinations were generated and the combining abilities were tested to screen the combinations with strong disease resistance and heterosis.【Result】The inbred line K36 were homozygous resistant at the three loci, qMrdd2, Rmrdd6 and qMrdd8 while S221 were homozygous susceptible. All the 263 RILs were genotyped into 21 patterns in terms of genetic composition of the three resistant loci. The lowest DSI (0.281) appeared when all the three loci were homozygous resistant while the highest DSI (0.776) appeared when the three loci were homozygous susceptible, which were consistent with the resistant and susceptible parents (0.257, 0.623). The order of DSI from low to high value for one homozygous resistant locus was Rmrdd6 (0.396), qMrdd8 (0.478) and qMrdd2 (0.654) when the other two loci were homozygous susceptible, which showed that Rmrdd6 and qMrdd2 performed the strongest and the weakest resistance while qMrdd8 was in the middle. The variation range of genetic distance between JR2136 with the genotype of three homozygous resistant loci and other 23 inbred lines was 0.2234-0.2895, with an average value of 0.2612. The inbred line with the smallest genetic distance was C413, and the largest was Chang7-2. According to the results of cluster analysis, JR2136 was classified into Reid group, hybrid combinations with inbred lines H92 and H521 belonging to Huanggai group performed strong disease resistance and heterosis.【Conclusion】The resistance of K36 to MRDD was controlled by three loci, qMrdd2, Rmrdd6 and qMrdd8, and it had quantitative genetic characteristics and gene additive effect. Maize varieties with homozygous resistant genotypes demonstrated the strongest disease resistance. The developed molecular markers closely linked with the three resistant loci have proved valuable tools in disease-resistant breeding and screening of resistant germplasm resources. It is feasible to use molecular markers for assisted selection and gene aggregation to select highly heterotic combinations with strong disease resistance.

Key words: maize rough dwarf disease, resistance gene, molecular marker-assisted selection (MAS), heterotic grouping, combining ability