Range-wide pattern of genetic variation in Colobanthus quitensis

Abstract

There is only one species representing Magnoliopsida which is considered as native to the Antarctic, i.e., Antarctic pearlwort (Colobanthus quitensis). Although it was intensively studied toward the morphophysiological adaptation to extreme environmental conditions of that area, there is still a lack of sufficient data on its genetic variability. Nine C. quitensis populations from Chile and the Maritime Antarctic were sampled to estimate the pattern of genetic variation in relation to the geographic distribution of analyzed populations and postglacial history of the species. The retrotransposon-based DNA marker system used in our studies appeared to be effective in revealing genetic polymorphism between individuals and genetic differentiation among populations. Although the level of polymorphism was low (9.57%), the Analysis of Molecular Variance showed that overall population differentiation was high (F ST = 0.6241) and revealed significant differentiation between the Northern and Southern Group of populations as well as the population from Conguillio Park. The observed genetic subdivision of C. quitensis populations was confirmed by Bayesian clustering and results of Principal Coordinates Analysis. The Southern Group of populations was characterized by generally higher genetic diversity, which was expressed by the values of the effective number of alleles, expected heterozygosity and by the distribution of private alleles. Our results suggest that the species may have survived the Last Glacial Maximum in refugia located both on the South American continent and in geographically isolated islands of the Maritime Antarctic, i.e., they support the concept of the multiregional origin of C. quitensis in Antarctica.

Angiosperms at the edge: Extremity, diversity, and phylogeny

“…Polemoniaceae (Ericales) also exhibit multiple major radiations in alpine areas of western North America; the radiation of most extant genera is of late Miocene date (Landis et al, 2018). Although most characteristic of dry habitats, there are also many highly cold-adapted plants in Caryophyllaceae (Caryophyllales), including one of two angiosperms indigenous to Antarctica (Koc et al, 2018). In Gentianaceae (Gentianales), Gentiana L. mostly comprises alpine plants.…”

The complete chloroplast genome ofColobanthus apetalus(Labill.) Druce: genome organization and comparison with related species

“…Colobanthus quitensis has been extensively studied to explore the morphological, physiological and biochemical features that constitute the basis of adaptation to extreme Antarctic conditions ( Bravo et al, 2007 ; Giełwanowska et al, 2011 ; Giełwanowska et al, 2014 ; Bascunan-Godoy et al, 2012 ; Navarrete-Gallegos et al, 2012 ; Pastorczyk, Giełwanowska & Lahuta, 2014 ; Cuba-Díaz et al, 2017 ). In contrast, very little is known about the genetic diversity of this species and the genus Colobanthus ( Androsiuk et al, 2015 ; Koc et al., in press ). The complete sequence of C. quitensis cp genome has been recently published ( Kang et al, 2016 ), and it paved the way for more sophisticated genomic studies.…”

Retrotransposon‐based genetic diversity of Deschampsia antarctica Desv. from King George Island (Maritime Antarctic)

“…Seven iPBS primers were used individually in a polymerase chain reaction (PCR) according to the protocol described by Kalendar et al. (2010) with some modifications (Androsiuk et al., 2015; Koc et al., 2018). The reaction conditions for each primer (temperature of primer hybridization) were determined empirically.…”