中国农业科学 ›› 2019, Vol. 52 ›› Issue (23): 4262-4273.doi: 10.3864/j.issn.0578-1752.2019.23.007

• 植物保护 • 上一篇    下一篇

黑龙江省稻瘟病菌无毒基因AVR-PibAVR-PikAvrPiz-t的检测与分析

孟峰,张亚玲(),靳学慧(),张晓玉,姜军   

  1. 黑龙江八一农垦大学农学院/黑龙江省植物抗性研究中心,黑龙江大庆 163000
  • 收稿日期:2019-05-30 接受日期:2019-08-01 出版日期:2019-12-01 发布日期:2019-12-01
  • 通讯作者: 张亚玲,靳学慧
  • 作者简介:孟峰,E-mail:xmfengf@126.com
  • 基金资助:
    黑龙江省自然科学基金(QC2011C046);黑龙江八一农垦大学学成、引进人才科研启动计划(XDB-2016-05);黑龙江省农垦总局科技攻关项目(HNK125A-08-06);黑龙江省农垦总局科技攻关项目(HNK135-02-02);黑龙江省教育厅项目(12521376)

Detection and Analysis of Magnaporthe oryzae Avirulence Genes AVR-Pib, AVR-Pik and AvrPiz-t in Heilongjiang Province

MENG Feng,ZHANG YaLing(),JIN XueHui(),ZHANG XiaoYu,JIANG Jun   

  1. College of Agronomy, Heilongjiang Bayi Agricultural University/Heilongjiang Plant Resistance Research Center, Daqing 163000, Heilongjiang
  • Received:2019-05-30 Accepted:2019-08-01 Online:2019-12-01 Published:2019-12-01
  • Contact: YaLing ZHANG,XueHui JIN

摘要:

【目的】检测黑龙江省稻瘟病菌(Magnaporthe oryzae)无毒基因AVR-Pib、AVR-PikAvrPiz-t在不同地区、年份间流行菌株的分布情况与变异机制,了解其等位基因的致病表型,为黑龙江省抗瘟品种布局提供参考依据。【方法】利用NCBI中公布的无毒基因序列对3个无毒基因AVR-Pib、AVR-PikAvrPiz-t的基因全长和编码序列(coding sequence,CDS)分别设计特异性引物,将2016年和2017年采自黑龙江省不同地区335个稻瘟病菌单孢分离菌株的DNA进行PCR扩增,通过琼脂糖凝胶电泳检测分析,并挑选不同带型和不同地区代表菌株的PCR产物进行测序。测序结果与相应无毒基因序列进行碱基与氨基酸序列的比较分析,并利用水稻抗性单基因系,对不同变异类型的稻瘟病菌菌株进行致病型测定。【结果】在PCR电泳检测中AVR-Pib、AVR-PikAvrPiz-t均出现特异性条带,说明这3个无毒基因在黑龙江省均有分布,并以不同分布频率与突变类型出现。3个无毒基因平均扩增频率分别为75.52%、87.16%和85.67%。其中AVR-Pib通过电泳检测与PCR产物测序检测出4种带型(无带、高带、中高带与低带)和5种变异类型AVR-Pib(1-1、1-2、2、3、3-1),基因型AVR-Pib-1-1、AVR-Pib-1-2、AVR-Pib-2和AVR-Pib-3-1为新发现的变异类型,其中基因型AVR-Pib-1-1和AVR-Pib-1-2均为转座子Pot2的插入,但插入位点不同;基因型AVR-Pib-2在阅读框上游存在小片段的插入;基因型AVR-Pib-3-1碱基序列与原序列比对有4处差异,即32(C/G)35(T/A)36(T/A)38(T/A),导致氨基酸翻译提前终止。对检测到的5种等位基因型进行致病型测定,分析发现除正常基因型AVR-Pib-3外,其他变异基因型无毒功能均已丧失。而AVR-Pik经PCR产物测序检测出7种等位基因型,AVR-Pik(D、A、B、C、E、F、F2),碱基序列的变化均导致氨基酸错义突变,7种等位基因型均已见报道。无毒基因AvrPiz-t通过电泳检测和PCR产物测序分析,发现2种带型(高带和正常带型)与4种基因型AvrPiz-t(A、B、C、D),其中AvrPiz-t-A为正常基因型;基因型AvrPiz-t-B在191位处有碱基A的插入,导致氨基酸翻译提前终止;基因型AvrPiz-t-C为新发现的等位基因型,其特点在于与A类型存在17(T/C)和19位处碱基C的插入,发生移码突变翻译提前终止;高带型对应的无毒基因型AvrPiz-t-D经测序验证为Pot3转座子的插入。4种基因型菌株分别接种水稻单基因系发现,AvrPiz-t-A可以被Piz-t识别表现无毒,AvrPiz-t(B、C、D)均不能被Piz-t所识别而表现为有毒性。【结论】黑龙江省稻瘟病菌无毒基因AVR-Pib、AVR-PikAvrPiz-t分布较为广泛,且变异类型丰富,研究结果可为选育和推广携带相应抗病基因的水稻品种提供参考。

关键词: 黑龙江省, 稻瘟病菌, 无毒基因, AVR-Pib, AVR-Pik, AvrPiz-t

Abstract:

【Objective】The objective of this study is to investigate the distribution and variation mechanism of avirulence genes AVR-Pib, AVR-Pik and AvrPiz-t in Magnaporthe oryzae strains from different regions and years in Heilongjiang Province, to understand the pathogenic phenotypes of different avirulence gene alleles, and to provide a reference for utilization and distribution of resistance cultivars in Heilongjiang Province.【Method】Based on the avirulence gene sequences published in NCBI, specific primers were designed to amplify full length and the coding sequence (CDS) regions of three genes, respectively. From 2016 to 2017, 335 M. oryzae strains in different regions of Heilongjiang Province were collected and isolated, and their DNA was PCR-amplified using avirulence genes primers and analyzed by agarose gel electrophoresis. The PCR products with different band patterns and from representative strains of different regions were selected for sequencing. The sequencing results were compared with the corresponding avirulence gene sequences for base and amino acid. The pathogenic phenotype of M. oryzae strains with different variant types was determined based on the rice resistance to single-gene lines.【Result】The specific bands of AVR-Pib, AVR-Pik and AvrPiz-t were detected in PCR detection and appeared in different distribution frequencies and mutation types, indicating that these 3 avirulence genes were all distributed in Heilongjiang Province. The average amplification frequency of the 3 avirulence genes was 75.52%, 87.16% and 85.67%, respectively. Among them, 4 types of band (bandless, high band, mid to high band and low band) of AVR-Pib were detected by electrophoresis analysis and 5 variant types AVR-Pib (1-1, 1-2, 2, 3, 3-1) were detected by PCR product sequencing. The genotypes AVR-Pib-1-1, AVR-Pib-1-2, AVR-Pib-2 and AVR-Pib-3-1 are newly discovered variant types, of which genotypes AVR-Pib-1-1 and AVR-Pib-1-2 are insertions of transposon Pot2 but with different insertion sites. The genotype AVR-Pib-2 has a small fragment insertion in the upstream of CDS region. The genotype AVR-Pib-3-1 base sequence has 4 differences from the original sequence, namely 32 (C/G) 35 (T/A) 36 (T/A) 38 (T/A), and the amino acid translation was terminated prematurely. Pathogenic analysis showed that except for the normal genotype AVR-Pib-3, the other alleles lost their avirulence functions. Seven AVR-Pik alleles (D, A, B, C, E, F, F2) were detected after PCR product sequencing, and the alterations in the nucleotide sequences of these alleles all resulted in amino acid missense mutations. The 7 AVR-Pik alleles have been reported previously. The avirulence gene AvrPiz-t was analyzed by electrophoresis and sequencing of PCR products, and 2 types of band (high band and normal band type) and 4 genotypes of AvrPiz-t (A, B, C, D) were revealed. Among them, AvrPiz-t-A is the original genotype, while AvrPiz-t-B has a base A insertion at position 191, causing premature termination of amino acid translation. Genotype AvrPiz-t-C is a newly discovered allelic type, characterized by the presence of a nucleotide variation at position 17 (T/C) and the insertion of base C at position 19 compared with type A, leading to the frameshift mutation and premature translation termination. The high band type avirulent genotype AvrPiz-t-D was sequenced and verified as having an insertion of the Pot3 transposon. Rice single-gene lines infection showed that the strains with AvrPiz-t-A were avirulent to Piz-t line due to Piz-t recognition, whereas the strains with AvrPiz-t (B, C, D) were virulent to Piz-t line due to lost the ability recognized by Piz-t.【Conclusion】The avirulence genes AVR-Pib, AVR-Pik and AvrPiz-t of M. oryzae in Heilongjiang Province are widely distributed and the types of variation are abundant. The results of this study can provide a reference for breeding and popularizing rice cultivars with corresponding disease-resistance genes.

Key words: Heilongjiang Province, Magnaporthe oryzae, avirulence gene, AVR-Pib, AVR-Pik, AvrPiz-t