Original Article

Heredity (1997) 79, 402–407; doi:10.1038/hdy.1997.174

Isozyme analysis of the reported origin of a new hybrid orchid species, Epipactis youngiana (Young's helleborine), in the British Isles

Stephen A Harris1,2 and Richard J Abbott1

  1. 1School of Biological & Medical Sciences, Sir Harold Mitchell Building, University of St Andrews, St Andrews, Fife KYI6 9TH, UK
  2. 2Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK

Correspondence: Richard J Abbott, School of Biological & Medical Sciences, Sir Harold Mitchell Building, University of St Andrews, St Andrews, Fife KYI6 9TH, UK. E-mail: rja@st-andrews.ac.uk

Received 1 November 1996.

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Abstract

A survey of isozyme variation in what has been recorded as a new hybrid orchid species in the British Isles, Epipactis youngiana (Young's helleborine), and its putative parent species, has cast doubt on its supposed origins, i.e. stabilization of a hybrid product via autogamy after hybridization between E. helleborine times E. leptochila or E. helleborine times E. phyllanthes. Contrary to expectation, E. youngiana was found to contain a high level of genetic diversity and a genotypic structure indicative of outcrossing. Moreover, at a Glasgow site it appears to be interbreeding with two of its putative parents, E. helleborine and E. leptochila, to form part of a hybrid swarm. From the isozyme data, it is possible to dismiss the idea that E. phyllanthes may have acted as a parent of E. youngiana; however, it cannot be ruled out that the 'new species' is merely a variant form of E. helleborine or an introduction rather than a product of hybridization.

Keywords:

British flora, Epipactis, hybrid, isozyme variation, orchid, speciation

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References

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