利用小麦SSR标记追踪大赖草染色体Lr.2、Lr.7、Lr.14及其片段

定位于小麦7个部分同源群上的337对SSR引物中有113对SSR引物可检测到大赖草与普通小麦基因组间多态性，对小麦一大赖草Lr．2、Lr．7和Lr.14的异附加系和易位系的进一步分析表明，小麦7BL上的SSR引物gwm112在大赖草染色体Lr．2上具有特异扩增位点，可用来追踪Lr．2；5AS上的SSR引物gwm205、5AL的gwml56和5DL上的gwm212在Lr．7和Lr．14中均有特异扩增产物，可用于追踪Lr．7和Lr．14；而7AL上的SSR引物gwm63仅在大赖草染色体Lr．7上具有扩增位点。这不仅揭示了Lr．7可能存在第5和第7部分同源群染色体重排，而且也表明将引物gwm205、gwm156、gwm212与gwm63相结合可分别追踪大赖草Lr.7和Lr．14染色体及其片段。利用这些SSR引物可追踪同一植株中不同的大赖草染色体；与簇毛麦染色体6V上的SCAR标记相结合，能追踪同一植株中的大赖草和簇毛麦染色体片段。

Tracing Leymus racemosus chromosome Lr.2,Lr.7,Lr.14 and their segments using wheat SSR

Three hundred thirty seven SSR primers mapped on 7 homoelogous groups of wheat were used to amplify the gDNA of Triticum aestivum and Leymus racemosus .113 primers of them could reveal the genetic polymorphism between wheat and L racemosus .Of 113 primers,gwm112(7BL)has a specific amplification on Lr 2 and can be used to trace Lr 2;primers gwm205(5AS),gwm156(5AL)and gwm212(5DL)can amplify specific bands both on Lr 7 and Lr 14 revealing that these three primer pairs can be used to trace Lr 7 and Lr 14.Combined with gwm63(7AL),which has a special amplification only on Lr 7,the four primers can be used to discriminate Lr 7 and Lr 14 chromosomes of L racemosus .This result also indicated that chromosome rearrangements might have occurred on chromosome Lr 7 during the evolution of L racemosus .These primers could trace different chromosomes of L racemosus in a plant.Combined with the SCAR marker of 6V chromosome of Haynaldia villosa ,the chromosomal segments of L racemosus and Hanaldia villosa could be detected.