基于ITS的贵州省30个树种的DNA条形码研究

Identification of 30 Treespeciesin Guizhou Province by DNA Barcoding Based on nrITS

本文对贵州省19科26属30种林木树种植物ITS序列进行PCR扩增及测序,用MEGA 5. 0软件对序列进行比对分析序列信息,用最近距离法计算种内及种间遗传距离,通过邻接法构建系统发育树。结果表明,供试树种的DNA总长度为506～684 bp,其中平均G+C含量为64%,种内平均遗传距离为0. 013,种间平均遗传距离为0. 236;基于ITS序列构建的聚类树显示,对30种林木树种的鉴定成功率为83%,因此,推荐ITS序列作为林木树种DNA条形码的候选序列。

In this paper,the ITS sequences of 30 tree species of 26 genera in 19 family of Guizhou Province were amplified and sequenced by PCR. The sequence information was analyzed by MEGA 5.0,the genetic distance within and between species was calculated by the nearest distance method,and the phylogenetic tree was constructed by the adjacency method.The results showed that the length of DNA sequencesfromthe tested species were 506-684 bp,the average content of G+C was 64%,the average intraspecies genetic distance was0. 013,and average interspecies genetic distance was 0. 236. The clustering tree based on ITS sequence showed that the success rate of identifying the 30 tree species was 83%.Therefore,the ITS sequence is recommended as a candidate sequence for DNA barcodes of tree species.