Systematics of subtribe Galinsoginae (Asteraceae)

向日葵属菊科是开花植物中最大的科之一。它们在世界许多地区无处不在，特别是那些以季节性干燥气候条件为主的地区。美洲大陆有大约一半的向日葵科物种和大部分向日葵部落的物种。该部落有几种重要的经济作物(葵花油)和许多具有园艺价值的属，如大丽花、万寿菊和百日菊。关于向日葵部落成员的分类学工作产生了大量的信息，这些信息最近由几位作者以部落的主要分类的形式合成。这些分类掩盖了一个事实，即我们仍然对该部落及其一些亚部落的主要属的生态、进化和形态知之甚少。亚族Galinsoginae大约有125种，主要分布在墨西哥，再往南到南美洲的厄瓜多尔。在这个群体中几乎没有达成一致的通用概念，从而导致物种分配的多样性；而且一些物种与其他部落成员表面上的相似性使问题变得更加复杂。德克萨斯大学的帕内罗博士正在收集尽可能多的亚族约115种的分子DNA证据和形态信息，以构建该亚族的系统发育框架，并确定被确认为属和亚属的谱系的可靠形态特征。在墨西哥南部厄瓜多尔的实地采集将与外国同事合作，为分子、细胞学和形态研究提供新材料。在分析中使用核遗传和母本遗传的叶绿体基因将有助于解开疑似杂交的案例，这也可能与亚族中已知的多倍体有关。一个目标是将分子和形态研究整合在一起，出版该组的分类学专著，并将相关材料张贴到U-Texas标本馆维护的网站上。

9903800PaneroThe sunflower family Asteraceae is one of the largest families of flowering plants. They are ubiquitous in many areas of the world, especially those dominated by seasonally dry climatic conditions. The American continents have approximately half of the species of the family and most of the species of tribe Heliantheae. The tribe contains several economically important crops (sunflower oil) and many genera of horticultural value such as dahlias, marigolds, and zinnias. Taxonomic work on members of tribe Heliantheae has produced a wealth of information that has been recently synthesized by several authors in the form of major classifications for the tribe. These classifications disguise the fact that we still know very little about the ecology, evolution, and morphology of the major genera of the tribe and some of its subtribes. Subtribe Galinsoginae has approximately 125 species distributed mainly in Mexico, and further south to Ecuador in South America. There is little agreement on generic concepts in the group, with a consequent multiplicity of shifting species assignments; and the problem is compounded by the superficial similarity of some species to members of other tribes. Dr. Panero at the University of Texas is amassing molecular DNA evidence and morphological information for as many of the ca. 115 species of the subtribe as possible, in order to construct a phylogenetic framework for the group and to determine reliable morphological features for the lineages recognized as genera and subgenera. Field collecting in Mexico south to Ecuador will provide new materials for molecular, cytological, and morphological investigations, in association with foreign colleagues. The use of both nuclear and maternally inherited chloroplast genes in the analyses will help disentangle cases of suspected hybridization, which is also likely to relate to the known polyploids in the subtribe. A taxonomic monograph of the group, integrating molecular and morphological studies, is one goal, along with associated materials being posted to the website maintained at the U-Texas Herbarium.