中文摘要：

近20年来,DNA序列已被广泛应用于植物各分类阶元的系统学研究中,为解决长期有争议的和亟待解决的系统进化问题提供了有力的证据。现以蔷薇科为例,概述了应用DNA片段进行植物分子系统研究的现状,详细剖析了应用DNA序列进行植物系统发育研究时常见的问题及其原因,提出了对存在多倍化、杂交起源和快速分化等复杂进化史的植物类群进行系统学分析时选用DNA序列的策略和注意事项。

英文摘要：

During the last twenty years, DNA sequences have been widely used in phylogenetic analyses of plants at the different taxonomic levels, and provided convincing evidence to solve the long-standing disputed or unsolved phylogenetic problems. In this paper, the current status of applications of DNA fragments in plant phylogenetic studies were briefly reviewed taking Rosaceae as an example, and the common troubles occurring in phylogenetic studies and the possible reasons were discussed in detail. Finally, the strategies and points for attention in selecting DNA sequences were proposed for phylogenetic reconstruction of plant taxa especially for plants that have undergone complex evolutionary processes such as hybridization, polyploidization and rapid radiation.