狸尾豆属的系统学研究与分类修订

Accurate species identification and clear taxonomic inferences are the essential foundation of biological studies. The problems have been existed on the taxonomy and systematics of some genera. The genus Uraria is estimated to contain ca. 20 species mainly distributed in tropical and subtropical Asia. Its boundary and systematic position has been controversial. Meanwhile, very little has been known about the species boundaries and interspecific relationships within this genus. Our goals of this proposal include: (1) Studying the variation patterns of major morphological characters within and among populations of Uraria species based on both specimen survey and field observations; (2) Carrying out cytological studies to obtain karyotype evidence for the taxonomy of the genus; (3) Reconstructing the phylogenetic relationships of the Uraria species and among related genera based on sequence data of 3-4 nuclear and 4-6 chloroplast DNA fragments. By combining the evidence from morphology, cytology and molecular data, we aim to clarify the genus boundary and species delimitation, to uncover the phylogenetic relationships of Uraria and its related genera, and to perform a taxonomic revision of Uraria.

准确的物种鉴定和清楚的分类背景是生物学研究的基础。目前，属及以下水平的植物分类和系统关系还存在较多的问题。狸尾豆属隶属于豆科山蚂蝗族，约有20种，主要分布于热带和亚热带的亚洲。长期以来，由于狸尾豆属植物的形态变异式样不清楚且缺少深入系统的研究，属的界定及分类地位一直存在争议，属内物种的界定及种间关系也不清楚。本项目拟以狸尾豆属及其近缘属中与之有争议的物种为研究对象，开展以下研究工作：在居群思想的指导下，对馆藏标本、野外采集的居群标本及移栽植株的形态性状进行观察、测量和统计分析，阐明形态性状的变异式样及分类价值；开展细胞学研究，获得核型方面的分类学证据；基于3-4个核基因和4-6个叶绿体基因，构建该属的系统发育关系。综合形态学、细胞学和分子系统学证据，澄清狸尾豆属的界定及系统位置、属内物种界定及种间关系，并完成该属的分类修订。

狸尾豆属隶属于豆科山蚂蝗族，约有20种，主要分布于热带和亚热带的亚洲。狸尾豆属的界定及分类地位一直存在争议，属内物种的界定及种间关系也不清楚。本研究在广泛取样基础上，综合利用形态学、细胞学和分子系统学证据对狸尾豆属及其近缘属的系统发育关系进行探讨，主要结果和结论如下：（1）探讨了狸尾豆属及近缘属的属间、种间种内形态变异，发现叶形、小叶数目、叶长、小叶长、小叶宽、二级侧脉数、主脉与二级侧脉夹角、花序类型等形态性状在狸尾豆属及近缘属中具有较高的分类价值；（2）探索了几何形态学方法在狸尾豆属及其近缘属分类中的应用；（3）补充了狸尾豆属及近缘属9个物种的基因组大小、染色体核型数据；（4）基于核基因和叶绿体片段重建了狸尾豆属及其近缘属的系统发育关系；（5）获得了狸尾豆属及其近缘属13种43个样品的叶绿体基因组数据，以及11种20个样品的转录组数据；（6）基于核基因和叶绿体基因片段构建的系统发育树的拓扑结构不一致，导致的原因可能有杂交渐渗，信息位点不足等；（7）狸尾豆属不是一个单系类群；（8）算珠豆属不成立，应并入狸尾豆属中；（9）台湾蝙蝠草、长圆叶山蚂蝗应并入狸尾豆属。本项目的开展，为狸尾豆属及近缘属的系统发育关系提供了新的认识，为其分类修订提供了重要证据。