Chloroplast microsatellites and mitochondrial nad1 intron 2 sequences indicate congruent phylogenetic relationships among Swiss stone pine (Pinus cembra), Siberian stone pine (Pinus sibirica), and Siberian dwarf pine (Pinus pumila)

Abstract

We studied the phylogenetic relationships among the three stone pine species, Pinus cembra, P. sibirica, and P. pumila, using chloroplast microsatellites and mitochondrial nad1 intron 2 sequences. The three chloroplast microsatellite loci combined into a total of 18 haplotypes. Fourteen haplotypes were detected in 15 populations of P. cembra and one population of P. sibirica, five of which were shared between the two species, and the two populations of P. pumila comprised four species-specific haplotypes. Mitochondrial intron sequences confirmed this grouping of species. Sequences of P. cembra and P. sibirica were identical, but P. pumila differed by several nucleotide substitutions and insertions/deletions. A repeat region found in the former two species showed no intraspecific variation. These results indicate a relatively recent evolutionary separation of P. cembra and P. sibirica, despite their currently disjunct distributions. The species-specific chloroplast and mitochondrial markers of P. sibirica and P. pumila should help to trace the hybridization in their overlapping distribution area and to identify fossil remains with respect to the still unresolved postglacial re-colonization history of these two species.

Phylogenetic relationships among domesticated and wild species of Cucurbita (Cucurbitaceae) inferred from a mitochondrial gene: Implications for crop plant evolution and areas of origin

“…Because of their low substitution rates (22) and high levels of gene rearrangements (23), plant mitochondrial genes have been regarded as less useful for systematic studies than animal mtDNA. However, the mitochondrial nad1 intron 2 has been successfully used in studying population structure and phylogenetic relationships among closely related taxa in conifers (24,25). Our results showed that this mitochondrial region possesses sufficient sequence variation to distinguish among Cucurbita species.…”

No reduction in genetic diversity of Swiss stone pine (Pinus cembra L.) in Tatra Mountains despite high fragmentation and small population size

“…3). Overall, the pattern of genetic differentiation of Swiss stone pine is rather shallow (Belokon et al 2005;Gugerli et al 2001Gugerli et al , 2009Höhn et al 2009), indicating recent fragmentation of a common gene pool that formerly occupied a larger range. …”

Lateglacial and Holocene vegetation history in the Insubrian Southern Alps—New indications from a small-scale site

“…With low moisture availability it is less competitive than P. sylvestris and P. mugo (Landolt 1977). In Siberia the distribution of P. sibirica, a very close relative of P. cembra (Gugerli et al 2001), is related to moisture availability, with P. sibirica growing on more humid and P. sylvestris on drier slopes (Walter 1974). The absence or irrelevance of P. cembra in the calcareous areas of Insubria could be explainable by lower overall soil-moisture availability.…”