DISSERTATION RESEARCH: The Genetic Basis of Local Adaptation: Serpentine Tolerance in Mimulus guttatus

自然景观往往是高度可变的，因此一个物种可能会在其分布范围内经历不同的选择压力。这种趋异选择可以驱动种群的适应性分化，维持遗传变异，促进物种形成。种群对当地生境的适应性经常得到证明，但在遗传水平上没有得到很好的表征。这项研究将着眼于适应蛇纹石土壤中Mimulus guttatus（常见的monkeyflower），以解决适应性分歧的遗传基础。土壤代表了一个特别恶劣的栖息地，大多数植物物种不能生存，然而，M。点滴藻既能在这些土壤上生长，也能在这些土壤上生长。该项目将使用高通量DNA测序技术来确定基因组中有助于对土壤条件耐受性差异的区域，测试这些基因组区域在田间的适应意义，并确定能够在蛇纹石土壤中生存的性状。描述适应异质环境的遗传基础可以为预测种群如何应对不断变化的环境提供重要的见解。此外，通过确定植物在富含金属、营养贫乏的土壤上生长所涉及的基因组区域，该项目可能对受采矿或其他活动影响的有毒土壤的植物补救以及作物育种产生影响，以提高对贫瘠或压力土壤的耐受性。该项目将包括高中和本科生的辅导以及公众的参与。

Natural landscapes are often highly variable such that a species is likely to experience different selective pressures across its range. Such divergent selection can drive the adaptive differentiation of populations, maintain genetic variation, and promote speciation. Adaptation of populations to their local habitat has frequently been demonstrated, but is not well characterized at the genetic level. This study will look at adaptation to serpentine soils in Mimulus guttatus (common monkeyflower) to address the genetic basis of adaptive divergence. Serpentine soils represent a particularly harsh habitat that most plant species cannot survive in; however, M. guttatus is able to grow both on and off of these soils. This project will use high-throughput DNA sequencing technology to identify regions of the genome that contribute to differences in tolerance to soil conditions, test the adaptive significance of these genomic regions in the field, and identify traits that enable survival on serpentine soils. Characterizing the genetic basis of adaptation to heterogeneous environments could provide important insights for predicting how populations may respond to changing environments. Furthermore, by identifying genomic regions involved in plant growth on metal enriched, nutrient poor soils this project could have implications for phytoremediation of sites affected by mining or other activities resulting in toxic soils as well as crop breeding to improve tolerance to poor or stressful soils. This project will include mentorship of high school and undergraduate students and the engagement of the general public.