应用RAPD特异标记分析拟鹅观草属部分物种的基因组组成

选用小麦族中8个基本基因组(E、H、I、P、St、W、Ns、R)的特异RAPD引物进行PCR扩增检测,分析Pseudoroegneriagracillima、P.kosaninii、Roegneriaalashanica和R.magnicaespes这4个四倍体物种的基因组组成。结果表明:P.gracillima、P.kosaninii、R.alashanica和R.magnicaespes中除了含有St或经修饰的St基因组外,都不含E、H、I、P、W、Ns和R基因组,由此推断P.gracillima和P.kosaninii至少含有一个St或经修饰的St基因组,另一个基因组是否为Y基因组,需要进一步研究证实。结合前人细胞遗传学研究的结果,推断R.alashanica和R.magnicaespes为同源四倍体或部分同源四倍体,其基因组组成为StStStSt或St1St1St2St2。因此,结合外部形态特征以及前人细胞遗传学、分子标记研究和核型分析的结果,推断R.alashanica和R.magnicaespes与P.elytrigioides一样,也可能是在中国分布的四倍体拟鹅观草属物种,为系统整理和研究国产拟鹅观草属物种及其地理分布提供了DNA分子水平上的资料。

The genome constitutions of some Pseudoroegneria species assessed by genome-specific RAPD markers

To analyze the genome constitutions of four tetraploid species,i.e.Pseudoroegneria gracillima,P.kosaninii,Roegneria alashanica and R.magnicaespes,eight different genome-specific RAPD primers were selected for PCR amplification reaction. The results indicated that these four tetraploid species had the St or slightly modified St genome but lacked the E,H,I,P,W and Ns genomes. It was concluded that P.gracillima and P.kosaninii contained at least one St or slightly modified St genome,while the other genome needed to be further studied if it was Y genome. According to genome-specific RAPD markers and the studies on cytogenetics,R.alashanica and R.magnicaespes were both auto-or allo-tetraploid species with StStStSt or St 1St 1St 2St 2 genomes. Therefore, it may suggest that R.alashanica and R.magnicaespes may be the species of Pseudoroegneria in China based on the morphology,cytogenetics,molecular marker and karyotypes. This study will also provide DNA molecular data for classification of Pseudoroegneria in China.