Genetic variation and reproductive mode in two epiphytic lichens of conservation concern: a transatlantic study of Evernia divaricata and Usnea longissima
2013 (English)In: Botany, ISSN 1916-2790, Vol. 91, 69-81 p.Article in journal (Refereed) Published
North European epiphytic lichens are often genetically impoverished compared with their North American counterparts.This has been hypothesized to impede sexual reproduction due to reduced chances of finding compatible mating typepartners. We compared genetic variation and reproductive mode in two threatened Scandinavian lichens, Evernia divaricata andUsnea longissima, with more viable populations in North America to see (i) if these species also show genetical depletion innorthern Europe and (ii) if the occurrence of sexual propagules (ascospores in apothecia) is more prevalent in genetically diversepopulations. Genetic variation of the fungal component was assessed by sequencing two nuclear rDNA gene regions (ITS and IGS)in 1005 and 1477 thalli, collected from 92 and 160 localities of E. divaricata and U. longissima, respectively. Scandinavian populationsof both species were almost devoid of genetic variation compared with much higher genetic diversity in North America.Wefound no support for the proposed relationship between genetic diversity and fertility. Fertile thalli were found in severalgenetically invariable populations. Fertility increased with population size and regional abundance in E. divaricata, but not inU. longissima. In Scandinavia, E. divaricata was more fertile than previously recorded, whereas all sampled populations ofU. longissima were sterile and possibly clonal.
Place, publisher, year, edition, pages
2013. Vol. 91, 69-81 p.
allelic richness, dispersal, epiphytic lichens, gene diversity, old-growth forests
Research subject Biology with specialization in Systematics
IdentifiersURN: urn:nbn:se:uu:diva-280072DOI: 10.1139/cjb-2012-0202OAI: oai:DiVA.org:uu-280072DiVA: diva2:909994