Pedicularis dasyantha shows unusually low
genetic diversity for a
flowering plant species. Studies of 13 geographically isolated populations in the Svalbard Archipelago revealed that among 31
enzyme-coding
loci examined, only one (
6-Phosphogluconate dehydrogenase, was
polymorphic. No
heterozygotes were detected in any population, consistent with the plant's
self-compatible reproductive system. The mean number of
alleles per locus at the species level was just 1.03, with only 3% of loci being polymorphic. These values are substantially lower than those found in most plant species, including other endemic plants with limited distributions. The distribution of
genetic variation shows a clear geographic pattern: populations in northwestern Svalbard predominantly contain one allele (referred to as allele 1), while populations in the southeast possess primarily a different allele (allele 2). Populations in the central "overlap" region show mixed frequencies of both alleles. This genetic structure corresponds with flower colour distribution – darker purple flower morphs are associated with allele 1, while lighter colour morphs correlate with allele 2. Multiple factors likely contribute to this limited genetic variation, including
founder effects from post-glacial colonization,
genetic drift in small isolated populations, and strong
natural selection in the harsh arctic environment. The plant's self-compatible reproductive system further reduces genetic exchange between individuals, leading to high
homozygosity. Despite having minimal genetic diversity compared to most plants,
P. dasyantha shows more variation than five other examined species in the genus
Pedicularis. ==References==