Collaborative Research: Phylogeny and Evolution of American Taxa of Acacia Subgenus Acacia

[04:14 . 90]金合欢属由灌木和乔木组成，在包括美洲在内的热带和亚热带世界的干旱植被中占主导地位。尽管金合欢具有重要的经济和生态意义，但其物种间的进化关系（系统发育）和数百种已描述物种间的形态进化趋势（如叶片、花和种子的进化）却知之甚少。伊利诺伊大学的David Seigler博士和爱荷华大学的Joseph Miller博士将从美洲、非洲、亚洲和澳大利亚的众多金合欢物种样本中积累新的质粒和核基因DNA序列数据。在墨西哥和多米尼加共和国的实地工作将补充来自旧大陆物种的同事提供的样本，为主要是美洲的金合欢亚属构建一个系统发育框架，并探索与那些被怀疑是近亲的非洲物种的关系，包括一些与美洲抗金合欢共生体非常相似的蚂蚁的共生关系。反过来，系统发育框架将有助于澄清有关物种划分、地理分布和类群命名的问题。对金合欢的系统分类学和系统发育学的进一步了解将有助于农学家、自然资源保护学家、生态学家和牧场管理者的工作，并将使这些植物的授粉生物学、根瘤固氮和生物地理学等有待解决的问题更加尖锐。将加强与拉丁美洲、非洲、澳大利亚和欧洲的科学同事的互动。学生将接受野外和实验室（植物标本室）研究方面的培训，并陪同研究人员到国外进行野外采集。交互式识别密钥将被发布到一个由澳大利亚研究人员维护的网站上，用于研究金合欢的生物学和进化。

0414902Miller The genus Acacia consists of shrubs and trees that are dominant in the arid vegetation of the tropical and subtropical world, including the Americas. Despite economic and ecological importance of acacias, the evolutionary relationships of the species (phylogenies) and morphological trends of evolution among the hundreds of described species (such as leaf, flower, and seed evolution) are poorly known. Collaborating researchers Dr. David Seigler at University of Illinois and Dr. Joseph Miller at University of Iowa will accumulate new DNA sequence data for plastid and nuclear genes from numerous species samples of acacias from the Americas, Africa, Asia, and Australia. Field work in Mexico and the Dominican Republic will complement samples supplied by colleagues from Old World species, to construct a phylogenetic framework for the largely American subgenus of acacias, and to explore relationships with those African species suspected to be close relatives, including some with symbiotic associations with ants remarkably similar to the American ant-acacia symbionts. In turn, the phylogenetic framework will help clarify issues concerning species delimitation, geographic distribution, and nomenclature in the group. Improved understanding of the systematics and phylogenetics of acacias will help agronomists, conservationists, ecologists, and rangeland managers in their work, and will sharpen questions to be addressed concerning pollination biology, rhizobial nitrogen fixation, and biogeography of these plants. Interactions will be strengthened with scientific colleagues in Latin America, Africa, Australia, and Europe. Students will be trained in field and laboratory (herbarium) studies, and will accompany the investigators on field collecting trips abroad. Interactive identification keys will be posted to a website maintained by Australian researchers for the study of acacia biology and evolution.