四种栎树EST-SSR信息分析

为开发栎属遗传多样性检测的SSR标记,分析了蒙古栎、无梗花栎、夏栎和欧洲栓皮栎EST-SSR的特点,结果表明蒙古栎的EST中3 209.46 bp有一个SSR,无梗花栎中每6 160.36 bp有一个SSR、夏栎中每5 883.30 bp有一个SSR,欧洲栓皮栎中每6 129.12 bp有一个SSR。蒙古栎、无梗花栎、夏栎和欧洲栓皮栎EST-SSR的平均长度分别为21.65 bp、21.1 bp、20.66 bp和20.65 bp。四种栎类中不同基元的EST-SSR的分布频率具有非常一致的特征,均是二基元、三基元和六基元的SSR分布频率最高,达20%以上。而四基元和五基元的SSR在四个种类中的分布不到0.05%。二基元的SSR中大于1%的SSR均是AG、CT、TC、GA、AT、TA基元,并且在蒙古栎、无梗花栎和夏栎中AG、CT、TC基元的分布频率最高,而在欧洲栓皮栎中是TC、GA、AG的分布频率最高;三基元的SSR中,含CAA、GAA、TCT、CTT的SSR在四种栎类中都存在。六基元的SSR中大于1%在四种栎类中出现的类型均较少,为0～4种。

Analysis of SSR Information in EST Resource of Four Quercus Species

In order to develop SSR marks for genetic diversity detection in Quercus, the characters of EST-SSR of Quercus mogolica, Quercus petraea, Quercus robur and Quercus suber were estimated. Results showed the average SSR density was one SSR per 3 209.46 bp of Q. mogolica, one SSR per 6 160.36 bp of Q. petraea, one SSR per 5 883.30 bp ofQ. petraea, one SSR per 6 129.12 bp ofQ. suber, and the average SSR length was 21.65 bp, 21.1 bp, 20.66 bp, and 20.65 bp, respectively. The dinucleotide, trinucleotide repeats and the hex nucleotide repeats were the most abundant detected of the four species, the value of each kind of the three repeats type accounted for more than 20%. However, the tetranucleotide pentanucleotide repeats accounted for less than 0.05%. AG, CT, TC, GA, AT, and TA motifs were the dinucleotide repeats that detected in all the four species. AG, CT, TC motifs were the most abundant in Q. mogolica, Q. petraea, Q. robur, and in Q. suber TC, GA, AG were the most abundant. Among the trinucleotide repeats CAA, GAA, TCT, CTT motifs were detected in all the four species. The type ofhexnucleotide repeats that accounted for more than 1% in the four species was small, with 0-4 types only.