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

在原生的地方稀有的布莱克威尔植物物种在它们被引进的地方往往变得丰富和广泛。已开始进行田间试验和温室研究，以确定入侵灌木野牡丹(野牡丹科)在其原产区(哥斯达黎加)和引种区(夏威夷)的丰度和栖息地分布的差异是否源于环境或遗传差异。这项研究将通过对原生种群和引进种群的遗传结构进行广泛的调查来加强，以确定夏威夷的种群在遗传变异方面是否与本地种群相似或恶化。这项研究将确定是否发生了繁殖系统或遗传结构的变化，这将影响毛冠鼠的侵袭性。本研究还将考察夏威夷群岛木本植物入侵的历史过程(引种次数、创始人效应的存在、引种后的适应)以及由此产生的不同基因类型的分布。这项研究首次比较了原生和引进地区木本植物的遗传变异和育种系统。有关这种物种在夏威夷的遗传多样性的信息将对设计有效的生物防治计划、匹配当地适应的基因-天敌对很有价值。

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.