Taxonomic and geographic variation of the Pinus mugo complex on chloroplast microsatellite markers

Abstract

The high mountain plants of Central and Southern Europe survived the glacial periods in the same mountain ridges, but at lower altitudes and possibly covering larger areas than during interglacials. This implies a high level of species differentiation between isolated mountain ridges. Pinus mugo complex, which includes P. mugo s.s. (Alps, Sudetes, Carpathians, Dynaric Alps, and Rhodopes), P. uncinata (Pyrenees and Alps), and P. uliginosa (Sudetes and neighbouring mountain ridges) is a good group to examine such a scenario. We screened 44 populations across the geographic range of the complex, using 10 cpSSR markers to study (1) taxonomic relations among P. mugo s.s., P. uncinata, and P. uliginosa and (2) genetic and phylogeographic structure in P. mugo s.s. and P. uncinata. Allelic combinations of 87 size variants produced a total of 757 haplotypes. Haplotypic diversity was high and similar in every species (0.997, 0.986 and 0.991, respectively). The highest divergence between haplotypes was observed in P. uliginosa (= 10.29). The AMOVA revealed that most of the overall genetic variation is explained by the within-population component (F_ST = 0.121, R_ST = 0.206) and by the geography (F_CT = 0.056, R_CT = 0.083). The differentiation between P. mugo s.s., P. uncinata, and P. uliginosa is explained by about 5% (P<0.001) of the total variation. Vicariant gene pools for the complex were identified in the Pyrenees, the Alps with the Tatra Mts, the Sudetes, and the East and South Carpathians along with the Balkan Mountains. The phylogeographic structure was observed in P. mugo s.l., P. mugo s.s., and P. uncinata. Results support the separate taxonomic status of P. uncinata and P. mugo s.s. and possible hybrid origin of P. uliginosa.

Key words:

• biogeography
• Coniferae
• genetic structure
• mountain plants
• phylogeography
• Pinaceae
• systematics

Acknowledgements

We would like to thank Professor Yakiv P. Didukh from NASU Botanical Institute in Kiev, Professor Roman Gout from UNFTU Department of Forestry in Lviv, Dr Josep M. Montserrat from the Botanical Institute of Barcelona, Dr C. Farkas from the Brasov Forest Faculty, Romania, the authorities of Karkonosze and Tatra National Parks in Poland for their valuable help during field work, help and assistance in plant material collection and Ewa Sztupecka for technical assistance in the laboratory work. The collection of plant material was made possible thanks to the cooperation between CSIC (Spanish Research Council) and PAS (Polish Academy of Sciences), NASU (National Academy of Sciences of Ukraine) and PAS, KWU (Kazimierz Wielki University), and UNFTU (Ukrainian National Forest-Technical University).

Data Archiving Statement

cpSSR data has been deposited in TreeGenes database (the TGDR Accession number: TGDR016).

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental data

Supplemental data for this article can be accessed at: http://dx.doi.org/10.1080/14772000.2016.1257518

Additional information

Funding

This work was supported by the Polish Ministry of Sciences [grant number 2P04C 018 29], [grant number 2P06L 04628], [grant number 6P04G 06016], [grant number NN303 360535]; Institute of Dendrology of Polish Academy of Sciences [statutory activity].