Phylogenetic Relationships in Dioscorea, The True Yams

薯蓣（真正的山药）的系统发育关系

• 批准号: 0129376
• 负责人: Geeta Bharathan
• 金额: $ 20.11万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0129376&HistoricalAwards=false
• 关键词: Phylogenetic; Relationships; Dioscorea; True; Yams

ABSTRACTA grant has been awarded to Geeta Bharathan at SUNY at Stony Brook to study the evolutionary relationships of Dioscorea (the true yams). Dioscorea is a large, economically important monocot genus that contains about 600 species of, mostly tropical, vines that grow in a range of habitats. Despite its traditional value as a tuber and medicinal crop (and, recently, in the pharmaceutical industry) the taxonomy of Dioscorea is in a mess. While a statement, over a 100 years ago, by the famous taxonomist, Hooker, that "...the species of Dioscorea are in a state of indescribable confusion" is slowly being remedied through heroic efforts by a great many alpha-taxonomists, the question of higher level relationships is a thorny one that traditional morphological approaches alone may not be able to resolve. In this project species of Dioscorea across the world will be sampled to study variation in molecules (DNA sequences of three genes) and morphology (observations on field and herbarium collections). Molecular sequences will be analyzed to formulate hypotheses of evolutionary relationships and to construct a systematic framework for the group. This will help to achieve several goals: 1) Evaluation of previous classifications to facilitate taxonomic revisions; 2) Evaluation of the evolutionary basis for particular subgroups (e.g., the one that includes the three North American species) to help understand the historical origins and biogeographical spread of this large genus; 3) Evaluation of morphological traits to improve their use in classification of the genus; 4) Compilation of a morphological data set for phylogenetic analysis, to be done in collaboration with Dioscorea scientists across the world.The wider significance of the achievement of the above objective has both scientific and societal aspects. The project would generate a rigorous systematic framework that then can be used to study various aspects of this important tropical crop: evolution of vegetative form and development (including leaf form and tuber-formation), biogeographical patterns of diversification, and history of domestication. All these would contribute to future uses and improvement of the crop. The project would enable training of students (graduate and undergraduate) in field and laboratory methods including morphology, while at the same time exposing them to important international issues involved in the collection and utilization of germplasm from other nations. The project has the explicit involvement of a Mexican collaborator for plant collection and mapping using GIS, and a course on phylogenetics to be taught in Mexico by the PI. All these activities will contribute to building 1) a scientific base of knowledge on an important, but understudied, tropical crop, 2) scientific skills and infrastructure at the national and international levels, and 3) international collaboration and scientific exchange.

摘要纽约州立大学斯托尼布鲁克分校的吉塔·巴拉坦获得了一笔研究金，用于研究番薯（真正的山药）的进化关系。红葡萄是一个经济上重要的单子叶植物大属，包含约600种，主要是热带，生长在一系列栖息地的藤蔓植物。尽管其作为块茎和药用作物的传统价值（以及最近在制药工业中的价值），但拟南芥的分类学仍处于混乱状态。100多年前，著名的分类学家胡克曾说过，“...山药属物种处于难以形容的混乱状态”正在通过许多阿尔法分类学家的英勇努力慢慢得到纠正，但更高层次的关系问题是一个棘手的问题，仅靠传统的形态学方法可能无法解决。在该项目中，将对世界各地的胡枝子物种进行采样，以研究分子（三个基因的DNA序列）和形态（对野外和植物标本馆收集的观察）的变化。 分子序列将被分析，以制定进化关系的假设，并为该组构建一个系统的框架。 这将有助于实现以下几个目标：1）评价以前的分类，以促进分类学修订; 2）评价特定亚组的进化基础（例如，包括三个北美种），以帮助了解这个大属的历史起源和地理分布：3）评价形态特征，以提高其在属分类中的应用; 4）汇编用于系统发育分析的形态学数据集，与世界各地的厄立特里亚科学家合作完成。实现上述目标的更广泛意义具有科学和社会意义。方面 该项目将产生一个严格的系统框架，然后可用于研究这一重要热带作物的各个方面：营养形态和发育的演变（包括叶片形态和块茎形成），多样化的地理模式和驯化历史。 所有这些都将有助于未来的用途和作物的改进。 该项目将使学生（研究生和大学生）能够接受包括形态学在内的实地和实验室方法的培训，同时使他们了解与收集和利用其他国家的种质有关的重要国际问题。 该项目有一名墨西哥合作者的明确参与，利用地理信息系统进行植物收集和绘图，并由PI在墨西哥教授植物遗传学课程。 所有这些活动都将有助于建立：1）关于一种重要但研究不足的热带作物的科学知识基础; 2）国家和国际层面的科学技能和基础设施; 3）国际合作和科学交流。