Polina Volkova, Alexey Shipunov, Polina Borisova, Reed Moseng, Ranelle Ivens. (2014). In search of hybridity: the case of Karelian spruces. Silva Fennica vol. 48 no. 2 article id 1072. https://doi.org/10.14214/sf.1072

Keywords: cpDNA; Picea; plant mtDNA; introgression; northern taiga

Highlights: Karelian spruces have morphology that is typical for P. obovata and characterized with genetic variation, described previously for P. abies; Karelian spruces evolved due to introgression between P. abies and P. obovata. However, it is unclear whether Karelian spruces could be treated as P. fennica, because unequivocal morphological and genetic characters of the latter are still absent.

Abstract | Full text in HTML | Full text in PDF | Author Info

Distribution ranges of spruces, European Picea abies and Siberian P. obovata intersect in the Eastern Europe and Urals, forming wide zone of introgressive hybridization where species discrimination is difficult. We applied both molecular (mtDNA and cpDNA sequences) and morphological approaches with goals of elucidating the origin of spruces in undisturbed forests of Russian Karelia (considered as part of the abovementioned introgression zone). Karelian spruces have morphology that is typical for P. obovata and characterized with genetic variation, described previously for P. abies. This contradiction between morphology and organellar DNA could be itself an evidence of hybrid origin because morphological data should have a genetic basis. If the genes responsible for the observed morphological differences are nuclear, that explains why we did not see any deviation of Karelian spruces towards P. obovata in organellar markers. In this situation nuclear gene flow from P. obovata should be performed via pollen. Thus, we should expect Karelian spruces to have cpDNA haplotypes (inherited paternally in conifers) typical for P. obovata. However, it is not the case for the majority of plants sampled and requires additional explanation like chloroplast capture in the introgresson zone. In all, we think that Karelian spruces evolved due to introgression between P. abies and P. obovata. However, it is unclear whether Karelian spruces could be treated as P. fennica, because unequivocal morphological and genetic characters of this hybridogenous species are still absent.

Volkova, Moscow South-West High School (No. 1543), 26 Bakinskikh komissarov str. 3–5, RU-119571 Moscow, Russia E-mail: avolkov@orc.ru
Shipunov, Department of Biology, Minot State University, Minot, North Dakota, USA 58707 E-mail: dactylorhiza@gmail.com
Borisova, Biological Department, Moscow State University, Vorobjevy Gory, RU-119899, Moscow, Russia E-mail: salixhastata@ya.ru
Moseng, Minot High School, Minot, North Dakota, USA 58701 E-mail: dactylorhiza@gmail.com
Ivens, Department of Biology, Minot State University, Minot, North Dakota, USA 58707 E-mail: dactylorhiza@gmail.com

article id 905, category Research article

Katarzyna A. Jadwiszczak, Danuta Drzymulska, Agata Banaszek, Piotr Jadwiszczak. (2012). Population history, genetic variation and conservation status of the endangered birch species Betula nana L. in Poland. Silva Fennica vol. 46 no. 4 article id 905. https://doi.org/10.14214/sf.905

Keywords: Betula nana; genetic diversity; microsatellites; conservation genetics; cpDNA; isolation

Abstract | View details | Full text in PDF | Author Info

The effective conservation of species requires data on the levels and distribution of genetic diversity within and among populations. In this study, we estimated the genetic variation in three isolated populations of Betula nana in Poland. An analysis of 11 nuclear microsatellites revealed moderate mean heterozygosities (H_O=0.556, H_E=0.562), low mean number of alleles per locus (A=4.57) and no inbreeding in the total sample. An M-ratio test indicated that each population had experienced a severe bottleneck in the past. Tests for heterozygosity excess revealed that a significant decrease in the numbers of individuals in two populations had occurred quite recently. The large number of private alleles and very restricted number of migrants between populations (Nm=0.35) strongly suggest that genetic drift and geographic isolation are the primary factors responsible for the reduction of genetic variation in the Polish populations of B. nana. We detected two cpDNA haplotypes in the study populations, which can be explained in terms of either the genetic drift acting on the relict localities or a postglacial recolonisation from distinct refugia. Palynological data indicated that one refugium could be located in the Carpathians and their northern foreland. The primary threat to B. nana in Poland is the overgrowth of its habitats by competing species, which has likely resulted in a lack of generative reproduction in the mountain populations.

Jadwiszczak, Institute of Biology, University of Białystok, wierkowa 20B, 15-950 Białystok, Poland E-mail: kszalaj@uwb.edu.pl
Drzymulska, Institute of Biology, University of Białystok, wierkowa 20B, 15-950 Białystok, Poland E-mail: dd@nn.pl
Banaszek, Institute of Biology, University of Białystok, wierkowa 20B, 15-950 Białystok, Poland E-mail: ab@nn.pl
Jadwiszczak, Institute of Biology, University of Białystok, wierkowa 20B, 15-950 Białystok, Poland E-mail: pj@nn.pl

Category : Review article

article id 923, category Review article

Katarzyna A. Jadwiszczak. (2012). What can molecular markers tell us about the glacial and postglacial histories of European birches? Silva Fennica vol. 46 no. 5 article id 923. https://doi.org/10.14214/sf.923

Keywords: Betula; cpDNA; glacial refugia; microsatellite; suture zone

Abstract | View details | Full text in PDF | Author Info

The last glaciation was one of the most severe of the Pleistocene epoch. The development of the Scandinavian ice sheet forced many species to reduce their ranges to areas with favourable climatic conditions. Most European species survived the Last Glacial Maximum in refugia in southern parts of Europe. Cold-tolerant species, such as birch trees and shrubs, could also inhabit western, eastern or central Europe. After climate warming, Holocene recolonisation began. This paper presents a comparative analysis of the genetic variation of four European Betula species to reconstruct their glacial and postglacial histories. Two chloroplast DNA haplotypes dominate within the ranges of all birch species, one haplotype is the most common in western and northwestern Europe, the second haplotype occurs mainly in the eastern and southeastern parts of the continent. This finding suggests that birches have recolonised Europe from the western and the eastern refugia, respectively. Most of Europe was likely populated from higher latitude refugia because there was no evidence of isolation by distance and weak genetic structures were detected. Similar patterns of haplotype distributions within Betula ranges indicate that postglacial recolonisation may be disturbed by interspecies hybridisation.

Jadwiszczak, Institute of Biology, University of Bialystok, wierkowa 20B, 15-950 Bialystok, Poland E-mail: kszalaj@uwb.edu.pl

Click this link to register to Silva Fennica.

If you are a registered user, log in to save your selected articles for later access.

Contents alert

Your selected articles

Follow @SilvaFennica