Genetic variation in Fitzroya cupressoides cultivated in the British Isles, assessed using RAPDs

Abstract

Fitzroya cupressoides (Molina) Johnston (Cupressaceae), a threatened conifer native to southern South America, has been cultivated in a number of gardens and arboreta in the British Isles since its introduction in 1849. In order to assess the importance of these cultivated trees for ex situ conservation, foliar samples were collected from 48 trees from throughout the British Isles, including five of known wild origin (Chile). DNA was extracted from these samples and assessed using the RAPD technique, in order to examine the extent of genetic variation. All samples from the cultivated trees of unknown origin, with one exception, were found to be genetically identical. In contrast, the five samples of known wild origin revealed pronounced polymorphism, varying from 5.3% to 49.1% between individuals. These results suggest that virtually all of the F. cupressoides trees currently cultivated in the British Isles have been derived from a single individual by vegetative propagation. Their value for ex situ conservation is therefore likely to be extremely limited. The implications of these results for the genetic conservation of other taxa in gardens and arboreta is discussed.