An Analysis of Factors Contributing to Hybrid Zone Expansion in the Piriqueta Caroliniana Complex

拟议的研究将检查促进新基因型传播的过程，这些新基因型是由形态和生态上不同的佛罗里达岩玫瑰（Piriqueta caroliniana）谱系之间的杂交产生的。通过自然杂交，不同分类群的混合被认为在各种植物和动物的历史上是重要的。然而，我们目前对扩展到广泛地理区域的杂交带的动态信息很少。杂交基因型的传播和杂交区扩大的过程会因杂交后早期的杂交破坏（丧失生存力和育性）而变得复杂。这项研究将检查杂交破坏的模式及其人口和遗传后果。将记录伴随杂交的适合度损失模式，并评估其对杂交带扩展过程的影响。本研究的结果将提供影响自然杂交的过程的信息，这些过程具有直接的经济和社会影响，包括；1)通过与本地物种杂交促进外来物种的传播，2)通过与本地和杂草物种杂交，基因从转基因作物中逃逸。此外，通过自然过程获得的优越基因型的发展信息可能在植物和动物育种计划中有应用。

The proposed research will examine the processes contributing to the spread of novel genotypes resulting from hybridization between morphologically and ecologically distinct lineages of the Florida rock rose (Piriqueta caroliniana). The mixing of divergent taxa via natural hybridization is considered to have been important in the history of a variety of plants and animals. However, we currently have little information on the dynamics of hybrid zones that extend over broad geographic regions. The process of spread of hybrid genotypes and expansion of the hybrid zone will be complicated by hybrid breakdown (loss of viability and fertility) in the early generations following hybridization. This research will examine patterns of hybrid breakdown and its demographic and genetic consequences. Patterns of fitness loss that accompanies hybridization will be documented and its impact on the process of hybrid zone expansion will be assessed.Results from this study will provide information on processes that affect aspects of natural hybridization that have direct economic and social impacts including; 1) the spread of exotic species that is facilitated by hybridization with natives, and 2) the escape of genes from genetically modified crops via hybridization with native and weedy species. Furthermore, information obtained on the development of superior genotypes through natural processes may have applications in plant and animal breeding programs.