Nazareno Alison Gonçalves, Neto Luiz Menini, Buzatti Renata Santiago de Oliveira, van den Berg Cássio, Forzza Rafaela Campostrini
Department of Genetics, Ecology and Evolution Federal University of Minas Gerais Belo Horizonte Brazil.
Rio de Janeiro Botanical Garden Rio de Janeiro Brazil.
Ecol Evol. 2020 May 5;10(11):4562-4569. doi: 10.1002/ece3.6148. eCollection 2020 Jun.
is a genus endemic to the eastern Brazilian Atlantic Forest, consisting of 12 accepted species. Some species, such as , , . , and . , referred to here as the PV complex, present extensive intra- and interpopulation morphological polymorphism, raising uncertainty regarding their circumscriptions. Although previous morphological analyses were used to solve the generic boundaries in the PV complex, persuasive genetic evidence is lacking. In order to test the hypothesis that the group under investigation contains only one taxon, amplification profiles of five intersimple sequence repeat (ISSR) markers were used to evaluate genetic diversity, genetic structure, and the relationships among the PV complex species. A total of 134 reproductive individuals were sampled in eight insular populations. Intrapopulation genetic analysis indicated low levels of genetic diversity. Analysis of genetic structure revealed that each of the eight sample locations can be considered unique biological populations as they are highly differentiated from each other. The Mantel test showed a high and positive correlation between genetic and geographic distance ( = .841, < .002), indicating isolation by distance. The results are consistent with that expected for plants with insular geographical distribution. When testing for the null hypothesis, the low levels of genetic variation among species ( = 0.155) suggest that the populations constitute only one highly polymorphic species with a wide distribution.
是巴西东部大西洋森林特有的一个属，由12个公认的物种组成。一些物种，如……，这里称为PV复合体，表现出广泛的种群内和种群间形态多态性，这使得它们的分类界定存在不确定性。尽管先前的形态学分析用于解决PV复合体中的属级界限问题，但缺乏有说服力的遗传证据。为了检验所研究的类群只包含一个分类单元的假设，使用了五个简单序列重复区间（ISSR）标记的扩增图谱来评估遗传多样性、遗传结构以及PV复合体物种之间的关系。在八个岛屿种群中总共采集了134个繁殖个体。种群内遗传分析表明遗传多样性水平较低。遗传结构分析显示，八个采样地点中的每一个都可被视为独特的生物种群，因为它们彼此高度分化。Mantel检验表明遗传距离与地理距离之间存在高度正相关（r = 0.841，P < 0.002），表明存在距离隔离。结果与岛屿地理分布植物的预期一致。在检验零假设时，物种间较低的遗传变异水平（FST = 0.155）表明这些种群仅构成一个分布广泛的高度多态性物种。
