Scholarlink

Background <p>Following historic natural disturbances, interspecific hybridization has been documented between several <i>Nothofagus</i> species in Chilean forests. While hybridization can contribute to survival by enhancing genetic diversity, it may lead to developmental instability, reflected in higher leaf fluctuating asymmetry. Our goal was to investigate if hybrid individuals between <i>N. pumilio</i> and <i>N. antarctica</i> had developmental instabilities observable through high leaf fluctuating asymmetry and to examine evidence of potential hybridization and population genetic structure across five <i>Nothofagus</i> species.</p> Results <p>We collected <i>N. pumilio</i>, <i>N. antarctica</i>, and putative hybrid leaves for morphological analysis and chloroplast DNA sequencing. We also performed population genetic analysis on additional <i>Nothofagus</i> species (<i>N. pumilio</i>, <i>N. antarctica</i>, <i>N. betuloides</i>, <i>N. dombeyi,</i> and <i>N. nitida</i>) using microsatellite markers (eight loci). The putative hybrids with intermediate phenotypes displayed significantly higher fluctuating asymmetry than morphologically unambiguous <i>N. pumilio</i> and <i>N. antarctica</i>. Yet despite clear phenotypic differences, <i>N. pumilio</i> and <i>N. antarctica</i> shared cpDNA and had almost identical microsatellite composition<i>.</i> Our microsatellite analysis of five <i>Nothofagus</i> species found high allelic variation within species and subpopulations but low genetic structure between species and populations.</p> Conclusions <p>Our findings reveal possible developmental instability in putative <i>N. pumilio</i> and <i>N. antarctica</i> hybrids characterized by leaf morphology. Though nuclear ITS sequences have phylogenetically differentiated pure <i>Nothofagus</i> taxa, we found little to no genetic differentiation between sympatric or allopatric <i>Nothofagus</i> species from microsatellite data, particularly <i>N. pumilio</i> and <i>N. antarctica</i>. This is a surprising result given the clear morphological and biogeographical differences between the Chilean <i>Nothofagus</i>. While <i>N. pumilio</i> and <i>N. antarctica</i> are named species, matching the ecological species concept, whole genome analyses is needed to test if they are distinct enough to be classified as separate species under the phylogenetic species concept.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Low population genetic structure in five Chilean Nothofagus species and high fluctuating asymmetry in Nothofagus pumilio x N. antarctica putative hybrids

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年10月1日

查看全文
  • Riley Yewon Jung,
  • Luana S. Maroja,
  • Shaw N. Lacy

摘要

Background

Following historic natural disturbances, interspecific hybridization has been documented between several Nothofagus species in Chilean forests. While hybridization can contribute to survival by enhancing genetic diversity, it may lead to developmental instability, reflected in higher leaf fluctuating asymmetry. Our goal was to investigate if hybrid individuals between N. pumilio and N. antarctica had developmental instabilities observable through high leaf fluctuating asymmetry and to examine evidence of potential hybridization and population genetic structure across five Nothofagus species.

Results

We collected N. pumilio, N. antarctica, and putative hybrid leaves for morphological analysis and chloroplast DNA sequencing. We also performed population genetic analysis on additional Nothofagus species (N. pumilio, N. antarctica, N. betuloides, N. dombeyi, and N. nitida) using microsatellite markers (eight loci). The putative hybrids with intermediate phenotypes displayed significantly higher fluctuating asymmetry than morphologically unambiguous N. pumilio and N. antarctica. Yet despite clear phenotypic differences, N. pumilio and N. antarctica shared cpDNA and had almost identical microsatellite composition. Our microsatellite analysis of five Nothofagus species found high allelic variation within species and subpopulations but low genetic structure between species and populations.

Conclusions

Our findings reveal possible developmental instability in putative N. pumilio and N. antarctica hybrids characterized by leaf morphology. Though nuclear ITS sequences have phylogenetically differentiated pure Nothofagus taxa, we found little to no genetic differentiation between sympatric or allopatric Nothofagus species from microsatellite data, particularly N. pumilio and N. antarctica. This is a surprising result given the clear morphological and biogeographical differences between the Chilean Nothofagus. While N. pumilio and N. antarctica are named species, matching the ecological species concept, whole genome analyses is needed to test if they are distinct enough to be classified as separate species under the phylogenetic species concept.