Graduate Program in Genetics and Molecular Biology, University of Campinas, Campinas-SP, Brazil.
Universidade do Sagrado Coração, Bauru-SP, Brazil.
PLoS One. 2018 Mar 7;13(3):e0192165. doi: 10.1371/journal.pone.0192165. eCollection 2018.
The primary focus of tropical forest restoration has been the recovery of forest structure and tree taxonomic diversity, with limited attention given to genetic conservation. Populations reintroduced through restoration plantings may have low genetic diversity and be genetically structured due to founder effects and genetic drift, which limit the potential of restoration to recover ecologically resilient plant communities. Here, we studied the genetic diversity, genetic structure and differentiation using single nucleotide polymorphisms (SNP) markers between restored and natural populations of the native tree Casearia sylvestris in the Atlantic Forest of Brazil. We sampled leaves from approximately 24 adult individuals in each of the study sites: two restoration plantations (27 and 62 years old) and two forest remnants. We prepared and sequenced a genotyping-by-sequencing library, SNP markers were identified de novo using Stacks pipeline, and genetic parameters and structure analyses were then estimated for populations. The sequencing step was successful for 80 sampled individuals. Neutral genetic diversity was similar among restored and natural populations (AR = 1.72 ± 0.005; HO = 0.135 ± 0.005; HE = 0.167 ± 0.005; FIS = 0.16 ± 0.022), which were not genetically structured by population subdivision. In spite of this absence of genetic structure by population we found genetic structure within populations but even so there is not spatial genetic structure in any population studied. Less than 1% of the neutral alleles were exclusive to a population. In general, contrary to our expectations, restoration plantations were then effective for conserving tree genetic diversity in human-modified tropical landscapes. Furthermore, we demonstrate that genotyping-by-sequencing can be a useful tool in restoration genetics.
热带森林恢复的主要重点一直是恢复森林结构和树种分类多样性，而对遗传保护的关注有限。通过恢复种植重新引入的种群可能具有较低的遗传多样性，并由于奠基者效应和遗传漂变而具有遗传结构，这限制了恢复恢复生态弹性植物群落的潜力。在这里，我们研究了巴西大西洋森林中本地树种 Casearia sylvestris 的恢复和自然种群之间使用单核苷酸多态性（SNP）标记的遗传多样性、遗传结构和分化。我们从每个研究地点的大约 24 个成年个体中采集叶子：两个恢复种植园（27 年和 62 年）和两个森林残余物。我们准备并测序了一个基于测序的基因分型文库，使用 Stacks 管道从头鉴定 SNP 标记，然后估计种群的遗传参数和结构分析。测序步骤成功用于 80 个采样个体。恢复和自然种群之间的中性遗传多样性相似（AR = 1.72 ± 0.005；HO = 0.135 ± 0.005；HE = 0.167 ± 0.005；FIS = 0.16 ± 0.022），种群没有遗传结构。尽管如此，我们发现种群内存在遗传结构，但在所研究的任何种群中都没有空间遗传结构。少于 1%的中性等位基因是种群特有的。总的来说，与我们的预期相反，恢复种植园在人为修改的热带景观中有效地保护了树木的遗传多样性。此外，我们证明了基因分型测序可以成为恢复遗传学的有用工具。
