Low genetic diversity in the Scottish endemic Primula scotica Hook.

Primula scotica Hook., a rare Scottish endemic, is threatened with extinction due to habitat destruction. A survey of genetic variability within the species was conducted on five populations from the Orkney islands and nine from the Scottish mainland. Isozyme analysis revealed variation between individuals at only one of 15 enzyme encoding loci examined, while a survey of DNA sequence variation via RAPD analysis revealed no genetic diversity either within or between a subsample of four populations surveyed. Individuals exhibited a 'fixed' heterozygous genotype at seven of the enzyme encoding loci, indicating that P. scotica is of allopolyploid origin. Despite the high level of heterozygosity per individual and the biochemical diversity that may stem from it, the species remains restricted to a very specific habitat. Implications for the conservation of the species are considered, including the need for habitat protection.