PRF: Spatial Genetic Structure and Genetic Demography of Delphinium nelsonii

由于有限的基因流动和空间异质性选择，大多数植物群体将在空间上形成遗传结构。然而，群体内遗传结构的精细尺度成因和后果尚不清楚。本研究旨在确定山地草本植物飞燕草（Delphinium nelsonii）群体精细尺度空间遗传结构的格局，并了解这种格局是如何产生的。将对两个种群进行分层取样，以在大范围的空间尺度上量化遗传结构。在每个群体中，来自生命周期的几个阶段的个体将使用同工酶电泳进行基因分型。成年种群结构将使用三种方法进行表征，并与花粉和种子传播距离的经验测量结果进行比较。遗传多样性和种群结构在不同生活史阶段的偏差将用于确定种群细分的时间和可能的机制。将使用两种技术来估计杂合性和近交对后代存活率的影响。不同空间接近性和遗传相似性组合的个体之间将形成控制杂交。在产生的后代中，将测量适合度的三个指标，即种子集实、种子质量和种子重量。方差分析将用于分解电泳标记位点遗传相似度和空间接近度对异交距离适应度影响的关系。

Most plant populations will be structured genetically in space as a result of restricted gene flow and spatially heterogeneous selection. However, the fine scale causes and consequences of within population genetic structure remain obscure. The proposed research is aimed at determining the pattern of fine scale spatial genetic structure in populations of the montane herb Delphinium nelsonii and understanding how the pattern is produced. Two populations will be sampled hierarchically to quantify genetic structure at wide range of spatial scales. In each population, individuals from several stages in the life cycle will be genotyped using isozyme electrophoresis. Adult population structure will be characterized using three methods and compared to patterns estimated from empirical measures of pollen and seed dispersal distances. Deviations in genetic diversity and population structure among different life history stages will be used to identify the timing and possible mechanisms of population subdivision. Two techniques will be used to estimate the effects of heterozygosity and inbreeding on offspring survival. Controlled crosses between individuals of different combinations of spatial proximity and genetic similarity will be made. Three measures of fitness, seed set, seed mass, and seed weight will be measured in the resulting progeny. Analysis of variance will be used to decompose the relationship of genetic similarity at electrophoretic marker loci and spatial proximity on the fitness consequences of outcrossing distance.