Allozyme variation and racial differentiation in Swedish Carex lepidocarpa s.l. (Cyperaceae)

Abstract

Two morphological races have previously been recognized within the sedge, Carex lepidocarpa, in Sweden. These largely allopatric races are accorded specific status, as C. lepidocarpa s.s. and C. jemtlandica, in Scandinavian floras. A study of allozyme variation in population from 80 Sweden sites supports the morphological evidence for racial differentiation within C. lepidocarpa. The two races differ from each other in terms of allele frequencies at polymorphic loci and also show different levels of within-population genetic diversity. Material that is morphologically referable to C. lepidocarpa s.s. is characterized by relatively high levels of allozyme variation, both within and between populations. Carex lepidocarpa s.s. is widespread in southern Sweden. In contrast, material that is morphologically assignable to C. jemtlandica shows low levels of within- population genetic diversity, and there is little differentiation between the geographically separated isolates of C. jemtlandica in northern Sweden and on the Baltic island of Gotland. The high degree of morphological similarity and moderate levels of genetic differentiation between the two races within C. lepidocarpa indicate that it is more appropriate to recognize the races as subspecies than as species. The low levels of genetic variation in C. jemtlandica, both within and between populations, suggest that C. jemtlandica may have arisen from C. lepidocarpa (or a near ancestor of C. lepidocarpa) as a result of population fragmentation and isolation in glacial refugia, or during the process of post-glacial colonization of Scandinavia. Lack of allozyme evidence for extensive hybridization between the two races of C. lepidocarpa, despite their ability to hybridize freely where their ranges overlap at present, supports the suggestion that the two races have had separate post-glacial histories.

• author: Hedrén, Mikael and Prentice, Honor C.
• publishing date: 1996
• type: Contribution to journal
• publication status: published
• keywords: Carex flava complex, Carex jemtlandica, geographic variation, historical processes, migration, plant
• in: Biological Journal of the Linnean Society
• volume: 59
• issue: 2
• pages: 179 - 200
• publisher: Oxford University Press
• external identifiers: scopus:0030459372
• ISSN: 0024-4066
• DOI: 10.1006/bijl.1996.0060
• language: English
• LU publication?: no
• additional info: Funding Information: We would like to thank Thomas Karlsson, Bengt Danielsson, Örjan Nilsson and Bengt M.P. Larsson for extensive help and interesting discussions, and Olle Jonsson and Håkan Tegelström for constructive comments on the manuscript. We are also grateful to all the people who helped us to locate C. lepidocarpa populations. The large collection of Carex material at the Uppsala Botanical Garden was taken care of by Bo Wilmer, Kerstin Lindvall and Stig Nilsson. Permission to collect plant material in nature reserves and in the Store Mosse National Park was granted by the environmental units at the appropriate regional administrative centres or by the Swedish Environmental Protection Board (SNV). The project was supported by grants from the Swedish Natural Science Research Council, NFR, (to MH and HCP) and from the Swedish Council for Forestry and Agriculture Research, SJFR, (to HCP). Copyright: Copyright 2017 Elsevier B.V., All rights reserved.
• id: 387bfbf8-78f1-434c-8dad-4b55e09fabcf
• date added to LUP: 2021-04-21 14:36:26
• date last changed: 2022-02-01 21:29:39