遗传 ›› 2008, Vol. 30 ›› Issue (7): 926-932.doi: 10.3724/SP.J.1005.2008.00926

• 研究报告 • 上一篇    下一篇

由基因序列开发番茄枯萎病抗性基因I-2的共显性分子标记

于拴仓1; 邹艳敏1, 2   

  1. 1. 国家蔬菜工程技术研究中心, 北京100097;
    2. 首都师范大学生命科学学院, 北京 100037

  • 收稿日期:2007-12-15 修回日期:2008-01-06 出版日期:2008-07-10 发布日期:2008-07-10
  • 通讯作者: 于拴仓

A co-dominant molecular marker of fusarium wilt resistance gene I-2 derived from gene sequence in tomato

YU Shuan-Cang1; ZOU Yan-Min1, 2   

  1. 1. National Engineering Research Center for Vegetable, Beijing 100097, China;
    2. College of Life Science, Capital Normal University, Beijng 100037, China

  • Received:2007-12-15 Revised:2008-01-06 Online:2008-07-10 Published:2008-07-10
  • Contact: YU Shuan-Cang

摘要: 根据I-2的基因序列设计特异扩增引物对I-2/5F和I-2/5R, 扩增I-2基因3 132~3 765 bp之间片段, 基因型为I-2 / I-2的材料03F-7可扩增出633 bp的条带, 而基因型为i-2/ i-2的材料Moneymaker可扩增出693 bp的条带, 杂合型材料可扩增出以上2个条带。通过这两个特异扩增片段的克隆和测序证明, 抗病材料扩增的633 bp片段为I-2基因的3 132~3 765 bp之间的序列, 而感病等位基因中出现大量的碱基突变和60 bp片段插入。利用引物对I-2/5F和I-2/5R, 可区分纯合抗病材料、杂合抗病材料和纯合感病材料, 从而建立了I-2基因的共显性分子标记。在此基础上, 利用该标记对16个主要番茄品种进行基因型鉴定, 8个品种含有I-2基因, 其中1个品种基因型为I-2 / I-2, 其他品种为I-2 / i-2。通过一次PCR和一次HindⅢ酶切建立了I-2和Tm-22双基因检测体系, 为多基因鉴定及标记辅助选择提供了有力工具。

关键词: 番茄, 枯萎病, I-2基因, 分子标记, Tm-22基因

Abstract:

Sequence-specific PCR primers, I-2/5F and I-2/5R were designed according to the sequence from 3 132 bp to 3 765 bp in I-2 gene. With them a 633 bp fragment was amplified from 03F-7 with a genotype of I-2 / I-2, 693 bp fragment from Moneymaker with a genotype of i-2/ i-2, and both fragments from Tebao with heterozygous genotype I-2 / i -2. These two specific fragments were cloned and sequenced. The results from multiple sequence alignment showed that the 633bp fragment from 03F-7 was identical with the sequence from 3 132 bp to 3 765 bp in I-2 gene. Compared with the sequence of I-2 gene, there were a large number of mutations and a 60 bp fragment inserted in susceptible alleles. The PCR primer com-bination, I-2/5F and I-2/5R can be used to distinguish homozygous resistant, heterozygous and homozygous susceptible materials, and it is a functional co-dominant marker in I-2 gene selection. Moreover, this marker was employed on 16 major tomato varieties for I-2 locus genotyping, in which half of the varieties contain I-2 gene, and only one variety is homozy-gous resistant. In addition, simultaneous detection system for I-2 and Tm-22 was established by a single PCR and a Hind III digestion. It provides a powerful tool for multiple genes selection in tomato breeding program.