基于ITS2序列的17种外来入侵植物分子鉴定

Molecular identification of 17 invasive plant species based on ITS2 sequences

中国入侵植物种类繁多、危害严重,对入侵物种的准确鉴定是开展各项研究的基础。本研究采用植物DNA条形码序列ITS2片段来探讨其在入侵植物中的鉴定能力。结果表明,ITS2序列在入侵物种及其近缘物种间存在明显的遗传差异,种间变异大于种内变异,在17种常见入侵植物与36种近缘物种的300份样品鉴定中成功率达95.5%。构建的NJ树可以很好地显示各不同入侵植物物种的聚类。此外,ITS2的二级结构也具有一定的系统学及分类学意义。因此,ITS2条形码序列能够作为入侵植物分子鉴定的有力工具,具有重要的应用价值。

A wide variety of invasive plants have caused ecological and economic problems in China. We explored the efficiency of molecular identification for the 17 popular aggressive invasive plant species and their relative species using ITS2 DNA regions. The results showed that ITS2 sequences possessed low intra-specific divergences and considerable inter-specific variations. ITS2 sequences could identify 95. 5% of 300 invasive plant and related species samples correctly at the species levels. The constructed NJ tree displayed that different invasive plant species separated well and the same invasive species clustered together. The secondary structures of ITS2 sequences are also important for the systematic and taxonomic study. Molecular identification based on ITS2 sequences might be a useful tool for the identification of invasive species.