PWT1, an Avirulence Gene of Magnaporthe oryzae Tightly Linked to the rDNA Locus, Is Recognized by Two Staple Crops, Common Wheat and Barley
PWT1, an Avirulence Gene of Magnaporthe oryzae Tightly Linked to the rDNA Locus, Is Recognized by Two Staple Crops, Common Wheat and Barley
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DOI：
10.1094/phyto-100-5-0436
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发表时间：
2010-05-01
期刊：
影响因子：
3.2
通讯作者：
Tosa, Yukio
中科院分区：
文献类型：
--
作者：
Chuma, Izumi;Zhan, Su-Wen;Tosa, Yukio
对小麦的致病性（Pwt1）基因座条件宿主稻瘟病菌对小麦的物种特异性。 GFSI 1-7-2（狗尾草分离株）在该位点携带无毒力等位基因（PWT1），而 Br48（小麦分离株）则携带毒力等位基因（pwt1）。将源自 GFSI 1-7-2 和 Br48 之间杂交的 F-1 培养物与 Br48 回交，产生其中 PWT1 单独分离的测试群体。当六倍体小麦品系接种 BC1F1 测试者时，它们都对所有 PWT1 携带者具有抗性，并且对所有磨坊携带者敏感，表明它们识别 PWT1。当大麦品种接种测试者时，它们表现出与六倍体品系相同的反应模式，表明大麦品种也识别 PWT1。这些结果表明，PWT1 是一个基本基因，普遍影响两种主要作物（六倍体小麦和大麦）上狗尾草分离株的无毒力。有趣的是，四倍体小麦品系不识别 PWT1。使用 F-1 和 BC1F1 群体进行的分子作图表明，Pwt1 基因座位于 2 号染色体上，并与核糖体 DNA 基因座和端粒紧密相连。
The pathogenicity to wheat (Pwt1) locus conditions host species specificity of Magnaporthe oryzae on wheat. GFSI 1-7-2 (Setaria isolate) carries the avirulence allele (PWT1) at this locus while Br48 (Triticum isolate) carries the virulence allele (pwt1). An F-1 culture derived from a cross between GFSI 1-7-2 and Br48 was backcrossed with Br48 to produce a tester population in which PWT1 alone segregated. When hexaploid wheat lines were inoculated with the BC1F1 testers, they were all resistant to all PWT1 carriers and susceptible to all mill carriers, suggesting that they recognize PWT1. When barley cultivars were inoculated with the testers, they showed the same pattern of reactions as the hexaploid lines, suggesting that the barley cultivars also recognize PWT1. These results suggest that PWT1 is a fundamental gene that universally conditions the avirulence of Setaria isolates on two staple crops, hexaploid wheat and barley. Interestingly, tetraploid wheat lines did not recognize PWT1. Molecular mapping using the F-1 and BC1F1 populations revealed that the Pwt1 locus is located on chromosome 2 and tightly linked to the ribosomal DNA locus and a telomere.