Genetic variability and differentiation among founder populations of the pitcher plant (Sarracenia purpurea l.) in ireland

Abstract

The pitcher plant (Sarracenia purpurea L.), a native North American species, presently grows on six sites in Ireland, these being the result of transplants (founder events) from «.n initial introduction to Termonbarry Bog in 1906. The extent and organisation of genetic variability among these populations was examined in this study. Of 25 enzyme systems investigated by starch gel electrophoresis, 14 showed specific activity. Eighteen loci suitab] for routine population screening were identified. Diallelic polymorphisms were observed at three loci, Pgm, 6Pg, ant Mdh-4. Genetic polymorphism at the Pgm locus has not previously been described. The overall level of genetic variation (max P = 17 per cent; max Hexp = 0·060) in Irish populations was low, but nevertheless within the range recorded for native North American populations. While it was evident that the severe founder events (2–4 individuals) had reduced the number of polymorphic loci there was lesser impact on heterozygos levels. Significant genetic differentiation among populations was found at all three polymorphic loci. © 1990 The Genetical Society of Great Britain.