Dissertation Research: Comparison of Genetic Variation and Breeding Systems of Clidemia hirta (Melastomataceae) Between Native and Introduced Populations

[0073246blackwell]在本地很稀有的植物物种，在被引进的地方往往变得丰富而广泛。为了确定在其原产地（哥斯达黎加）和引入地（夏威夷）观察到的入侵灌木Clidemia hirta （Melastomataceae）的丰度和栖息地分布的差异是由环境差异还是遗传差异造成的，已经开展了实地试验和温室研究。这项研究将通过对本地和引进的C. hirta种群的遗传结构进行大规模调查来确定夏威夷的这些种群在遗传变异方面是否与本地种群相似或不同，从而加强研究。这项研究将确定繁殖系统或遗传结构的变化是否已经发生，这将影响C. hirta的入侵。入侵的历史过程（引进的数量，奠基者效应的存在，引进后的适应）以及由此导致的不同基因型在夏威夷群岛之间的分布也将被检查。本研究首次比较了一种木本植物在原生地和引种地的遗传变异和育种系统。关于夏威夷这种物种的遗传多样性的信息对于设计有效的生物控制计划将有价值，这些计划将匹配当地适应的基因型-天敌对。

0073246BlackwellPlant species that are rare where they are native often become abundant and widespread where they are introduced. Field experiments and greenhouse studies have been initiated to determine whether the observed differences in the abundance and habitat distribution of the invasive shrub Clidemia hirta (Melastomataceae) in its native area (Costa Rica) and area of introduction (Hawaii) result from environmental or genetic differences. This research will be enhanced by conducting a broad-scale survey of the genetic structure of native and introduced populations of C. hirta to determine whether those in Hawaii are similar or depauperate in genetic variation to those in the native range. This study will determine whether shifts in the breeding system or genetic structure have occurred that would affect the invasiveness of C. hirta. The historical process of the invasion (numbers of introductions, presence of founder effects, adaptation after introduction) and the resulting distribution of different genotypes among the Hawaiian Islands will also be examined.This study is the first comparison of genetic variation and breeding system of a woody plant between its native and introduced areas. Information about the genetic diversity of this species in Hawaii will be valuable for devising effective biological control programs that match locally adapted genotype-natural enemy pairs.