利用叶绿体全基因组的单核苷酸多态位点对鹅掌楸和北美鹅掌楸的分子鉴定

Molecular Identification of Liriodendron chinense and L. tulipifera Based on Single-Nucleotide Polymorphic Sites from the Complete Chloroplast Genomes

摘要: 鉴定植物是人类认识自然的重要内容之一。由于工作量巨大，经历了漫长而艰辛的研究历程。标本馆和植物园为植物鉴定研究提供了重要支撑。基于形态分类的植物志的出版是植物鉴定研究进展过程中的里程碑式的工作。新的研究阶段需要从全球视角开展植物鉴定研究。植物的种间、属间甚至科间存在或多或少的形态相似性，用于植物分类的有价值的形态性状数量少。形态特征和基于DNA短片段的标记提供的信息量有限，学界期待分辨率高的植物种鉴定技术。高通量测序技术使植物叶绿体全基因组序列的获得成为可能。我们首次利用叶绿体基因组的499个单核苷酸多态位点，研制北美鹅掌楸和鹅掌楸的分子鉴定检索表。分析结果显示，在鹅掌楸属内的物种形成过程中，叶绿体全基因组内有75个基因和64个基因间隔区发生了种级水平的遗传分化。本研究利用了叶绿体全基因组序列提供的丰富的单核苷酸多态位点信息，可为鹅掌楸属植物资源的深入研究、保护和利用提供技术基础。

Abstract: Identification of plants is one of the important contents for human to understand nature. Due to the huge workload, it has gone through a long and arduous research process. Herbaria and botanical gardens provide important support for plant identification research. The publication of Flora based on morphological classification is a milestone in the advances of plant identification research. In the new stage, plant identification research should be carried out from a global perspective. There are more or less morphological similarities among species, genera and even families, the number of valuable morphological characters for plant classification is fewer. Morphological characteristics and DNA fragment-based markers could only provide limited information for plant identification. New technologies with high resolution are highly expected. High throughput sequencing technology makes it possible to obtain the whole chloroplast genome sequence of plants. For the first time, we compiled a molecular identification key to Liriodendron chinense and L. tulipifera using 499 single-nucleotide polymorphic sites from the chloroplast genomes. Our analysis indicated that, during speciation in the genus Liriodendron, genetic differentiation occurred in 75 gene regions and 64 intergenic regions in the chloroplast genomes at species level. This study that utilized the richer bio-information of single-nucleotide polymorphic sites from the complete chloroplast genomes would provide technical support for deeper study on plant resources in Liriodendron and their conservation and utilization.