A single gene with pleiotropic effects accounts for the Scottish endemic taxon Athyrium distentifolium var. flexile

H S McHaffie; C J Legg; R A Ennos

doi:10.1046/j.0028-646X.2001.00269.x

A single gene with pleiotropic effects accounts for the Scottish endemic taxon Athyrium distentifolium var. flexile

New Phytol. 2001 Dec;152(3):491-500. doi: 10.1046/j.0028-646X.2001.00269.x.

Authors

H S McHaffie¹, C J Legg², R A Ennos²

Affiliations

¹ The Royal Botanic Garden Edinburgh, Inverleith Row, Edinburgh EH3 5LR, UK.
² Institute of Ecology and Resource Management, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JU, UK.

PMID: 33863000
DOI: 10.1046/j.0028-646X.2001.00269.x

Abstract

• Experiments were conducted to determine the genetic relationship between the alpine fern Athyrium distentifolium and the Scottish endemic taxon A. distentifolium var. flexile. • Segregation of the taxa was studied after growing sporophytes from spore families, and after selfing and crossing gametophytes. The growth of both gametophytes and sporophytes was measured under a range of nutrient regimes. • The distinction between the two taxa is due to variation at a single gene with pleiotropic effects expressed at both the sporophyte and gametophyte stages. A. distentifolium sporophytes (genotypes A^D /A^D or A^D /A^F ) are taller, have fewer fronds, and produce fewer spores than A. distentifolium var. flexile sporophytes (genotype A^F /A^F ). Gametophytes containing the A^F allele have a 50% higher growth rate than those with the A^D allele on a range of media. • The polymorphism may be maintained by a balance between selection for and against the A^F allele at the gametophyte and sporophyte stages of the life cycle, respectively. Implications for the conservation of the A. distentifolium var. flexile taxon are discussed.

Keywords: Athyrium distentifolium var. flexile; Scotland; endemic; genetic conservation; pleiotropic; polymorphic populations.