Isozymic and chromosomal evidence for the allotetraploid origin of Gymnocarpium dryopteris (Dryopteridaceae).

Journal Article (Journal Article)

A critical examination of isozyme, chromosomal, and morphological characters in subspecies formerly included in Gymnocarpium dryopteris demonstrated that three sexual taxa can be distinguished. We recognize these taxa as distinct species: the widespread, fertile allotetraploid G. dryopteris, with one genome derived from the western diploid G. disjunctum and the other from G. appalachianum sp. nov., a previously undetected eastern North American diploid, which is described and illustrated here and for which we report a chromosome number of 2n = 80. Population comparisons of allele frequencies between C. disjunctum and G. appalachianum yielded an average Nei's genetic identity value (I) of 0.274. A wide-ranging assemblage of putatively triploid plants with both sterile, malformed spores and large, round spores capable of germination is believed to represent the backcrosses G. disjunctum X dryopteris and G. appalachianum X dryopteris. The name G. X brittonianum comb. nov. is applied here to G. disjunctum X dryopteris. A key to fertile species, species descriptions and illustrations, distribution maps, and habitat notes are included.

Full Text

Duke Authors

Cited Authors

  • Pryer, KM; Haufler, CH

Published Date

  • March 1, 1993

Published In

Volume / Issue

  • 18 / 1

Start / End Page

  • 150 - 172

Pubmed Central ID

  • AGR:IND93010310

Electronic International Standard Serial Number (EISSN)

  • 1548-2324

International Standard Serial Number (ISSN)

  • 0363-6445

Digital Object Identifier (DOI)

  • 10.2307/2419795

Language

  • eng