Plant Conservation and Population Biology, Biology Department, University of Leuven, Kasteelpark Arenberg 31, B-3001 Heverlee, Belgium.
Mol Ecol. 2012 Sep;21(17):4206-15. doi: 10.1111/j.1365-294X.2012.05698.x. Epub 2012 Jul 13.
Colonization is crucial to habitat restoration projects that rely on the spontaneous regeneration of the original vegetation. However, as a previously declining plant species spreads again, the likelihood of founder effects increases through recurrent population founding and associated serial bottlenecks. We related Amplified Fragment Length Polymorphism markers genetic variation and fitness to colonization history for all extant populations of the outcrossing terrestrial orchid Dactylorhiza incarnata in an isolated coastal dune complex. Around 1970, D. incarnata suffered a severe bottleneck yet ultimately persisted and gradually spread throughout the spatially segregated dune slacks, aided by the restoration of an open vegetation. Genetic assignment demonstrated dispersal to vacant sites from few nearby extant populations and very limited inflow from outside the spatially isolated reserve. Results further indicated that recurrent founding from few local sources resulted in the loss of genetic diversity and promoted genetic divergence (F(ST) = 0.35) among populations, but did not influence population fitness. The few source populations initially available and the limited inflow of genes from outside the study reserve, as a consequence of habitat degradation and spatial isolation, may have magnified the genetic effects of recurrent population founding.
在依赖原生植被自然再生的栖息地恢复项目中，定植是至关重要的。然而，随着曾经衰退的植物物种再次扩散，通过反复的种群建立和相关的连续瓶颈，奠基者效应的可能性增加。我们将扩增片段长度多态性标记的遗传变异和适应性与隔离海岸沙丘复合体中所有现存的陆生杂交兰花 Dactylorhiza incarnata 种群的定植历史联系起来。大约在 1970 年，D. incarnata 经历了严重的瓶颈，但最终得以幸存并逐渐在空间隔离的沙丘洼地中传播，这得益于开放植被的恢复。遗传分配表明，从附近少数现存种群向空旷地点的扩散，以及从空间隔离保护区外非常有限的流入。结果进一步表明，少数本地来源的反复建立导致遗传多样性的丧失，并促进了种群之间的遗传分化（F（ST）= 0.35），但没有影响种群适应性。最初可用的少数源种群以及由于栖息地退化和空间隔离而导致的研究保护区外基因的有限流入，可能放大了反复种群建立的遗传效应。
