Dissertation Research: The Systematics and Evolution of Jaltomata (Solanaceae)

PI 提议对 Jaltomata 的分类学、系统发育关系模式和进化过程进行研究。 茄科的一个新热带、草本至成熟的属。 这个人们对这个知之甚少且分类学混乱的属中的一个物种特别感兴趣，因为它正在墨西哥作为水果作物进行逐步驯化；人类也食用其他几种物种的水果和根茎。 PI 将构建基于叶绿体 DNA 的系统发育。 基于这种严格构建的系统发育学，将测试独立衍生的形态和核型进化以及生物地理学模式。 他们还将探索育种系统的演变。 由于多种原因，Jaltomata 特别适合研究进化过程和模式。 通用边界提出了一个具有挑战性的问题；一些工人保留了管状花的 Jaltomata 物种作为 Hebecladus，而 Saracha 和酸浆物种则被视为 Jaltomata。 物种之间存在很大的形态多样性（习性、外貌、花冠形状和颜色等）。 因此，该小组适合研究形态进化，因为它与系统发育、染色体进化、海拔/栖息地偏好的进化和繁殖系统进化有关。 该属包括多种育种系统，例如自花受精、兼性自花受精和专性异交。

The PIs proposed a study of the taxonomy, pattern of phylogenetic relationships and evolutionary processes in Jaltomata. A neotropical, herbaceous to suffrutescent genus of the Solanaceae. One species of this poorly understood and taxonomically confused genus is of particular interest because it is undergoing progressive domestication in Mexico as a fruit crop; fruits and root-stocks of several other species are also consumed by humans. The PIs will construct a chloroplast DNA-based phylogeny. Based on this rigorously constructed phylogeny, independently derived patterns of morphological and karyotypical evolution and biogeography will be tested. They will also explore evolution of breeding systems. Jaltomata is especially suitable for the study of evolutionary process and pattern for several reasons. Generic boundaries present a challenging problem; some workers retain the tubular flowered Jaltomata species as Hebecladus, and species of Saracha and Physalis have been treated as Jaltomata. There is much morphological diversity among species (habit, vestiture, corolla shape and color, etc.). The group, therefore, lends itself to the study of morphological evolution as it relates to phylogeny, chromosomal evolution, the evolution of altitude / habitat preference and breeding system evolution. The genus includes a diversity of breeding systems such as autogamy, facultative autogamy, and obligate outcrossing.