利用已知植物抗病基因编码氨基酸保守区域NBS-LRR（核苷酸结合位点-富亮氨酸区域）设计了42个简并引物组合，运用抗病基因类似物多态性（resistance gene analog polymorphism，RGAP）分子标记技术，对中国春、中国春-长穗偃麦草双二倍体及其附加系和代换系基因组DNA进行PCR扩增。结果表明，共有38对引物组合获得扩增产物，其中35对在普通小麦中国春、中国春-长穗偃麦草双二倍体中能扩增出多态性，平均每个引物组合扩增出38.5个片段。在普通小麦背景下，共获得275条长穗偃麦草E基因组多态性谱带，占扩增总谱带数的17.44%，揭示出在普通小麦背景下E基因组和普通小麦A、B、D基因组间的高丰度遗传变异。另外，利用RGAP分子标记技术，构建了一套完整的长穗偃麦草1E~7E染色体的特异RGAP标记。为小麦背景中长穗偃麦草外源遗传物质的快速检测提供了新途径。
The wild species of common wheat were confirmed to have many agronomically useful characters such as tolerance to salt stress, resistance of diseases and high quality. Interest in Lophopyrum elongatum as a source of genes for wheat improvement has been enhanced by the development of its amphiploids and addition, subbstitution and translocation lines. In order to rapidily further exploit and utilize key genes in this wild species of wheat, in this paper, forty-two degenerate primers, which were designed from the conserved motifs of known plant resistance gene products, were used to amplify the resistance gene analog polymorphisms (RGAP) from the genomic DNAs of common wheat cultivar Chinese Spring (CS), Lophopyrum elongatum, CS-Lo. elongatum ampliploid, and their addition and substitute lines. The amplification products could be obtained from 38 primers combinations, among which 35 primers combinations could amplify the polymorphic fragments between CS and CS-Lo. elongatum ampliploid, with an average of 38.5 bands per primers combination. A total of 275 bands were detected on Ee genome of Lo. elongatum in Chinese Spring background, with a polymorphic frequency of 17.44%, indicating that Ee genome showed high genetic diversity in common wheat background. To establish a set of specific resistance gene analogues markers for E chromosomes, RGAP molecular marker technology was used with 26 primer combinations to reveal polymorphism between Chinese Spring and the amphiploid, and the polymorphic bands also appeared in their addition and substitute lines, respectively. This indicated that the polymorphic bands were the specific RGAP markers of E chromosomes. A total of 30 specific RGAP markers, which were distributed in the diferent E specific chromosomes, were detected. The development of chromosome-specific markers of Lo. elongatum could be useful for scanning the alien chromosomes or chromosome fragments of Lo. elongatum in common wheat backgrounds.
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