Abstract
Postglacial climate changes alter geographical distributions and diversity of species. Such ongoing changes often force species to migrate along the latitude/altitude. Altitudinal gradients represent assemblage of environmental, especially climatic, variable factors that influence the plant distributions. Global warming that triggered upward migrations has therefore impacted the alpine plants on an island. In this study, we examined the genetic structure of Juniperus morrisonicola, a dominant alpine species in Taiwan, and inferred historical, demographic dynamics based on multilocus analyses. Lower levels of genetic diversity in north indicated that populations at higher latitudes were vulnerable to climate change, possibly related to historical alpine glaciers. Neither organellar DNA nor nuclear genes displayed geographical subdivisions, indicating that populations were likely interconnected before migrating upward to isolated mountain peaks, providing low possibilities of seed/pollen dispersal across mountain ranges. Bayesian skyline plots suggested steady population growth of J. morrisonicola followed by recent demographic contraction. In contrast, most lower-elevation plants experienced recent demographic expansion as a result of global warming. The endemic alpine conifer may have experienced dramatic climate changes over the alternation of glacial and interglacial periods, as indicated by a trend showing decreasing genetic diversity with the altitudinal gradient, plus a fact of upward migration.
Highlights
As planet Earth faces rising temperatures linking to escalating anthropogenic greenhouse gas emissions, global changes in its climate are greatly influencing the abundance and PLOS ONE | DOI:10.1371/journal.pone.0161713 August 25, 2016Postglacial Shrinkage of Juniperus morrisonicola in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Noncoding spacers trnS-trnG and trnT-trnL of chloroplast DNA (cpDNA) [16] and coxI (Tetraclinis articulata: EU161447) and coxIII (Juniperus formosana: EU182939) of mitochondrial DNA (mtDNA), and nuclear genes of Chs, Maldehy, Myb, Needly, and Pgi [17,18] were amplified by the polymerase chain reaction (PCR) using the primers listed in S1 Table
Sequences of 2 chloroplast DNA spacers, 2 mitochondrial DNA markers, and 5 nuclear loci were obtained from samples of J. morrisonicola
Summary
Nine populations of J. morrisonicola throughout its entire range of distribution in Taiwan were sampled. No protected or endangered species were involved, so no permit was required to collect tissue in any location sampled in this study. Healthy leaves were collected and dried in silica gel for total genomic DNA extraction using the cetyltrimethylammonium bromide procedure [15]. Noncoding spacers trnS-trnG and trnT-trnL of cpDNA [16] and coxI (Tetraclinis articulata: EU161447) and coxIII (Juniperus formosana: EU182939) of mtDNA, and nuclear genes of Chs, Maldehy, Myb, Needly, and Pgi [17,18] were amplified by the polymerase chain reaction (PCR) using the primers listed in S1 Table. PCR products were electrophoresed on agarose gels, purified using a gel extraction method. Purified plasmid DNA was sequenced on an ABI 3730XL automated sequencer (Applied Biosystem, USA)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
