Genetic variations in the endangered aquatic plant Nymphoides coreana (Menyanthaceae) in south-western Japan

Abstract

We surveyed allozyme variations among ten Nymphoides coreana populations in southwestern Japan. The percentage of polymorphic loci, the mean number of alleles per locus, and the effective number of alleles per locus varied little among populations. The observed heterozygosity and expected heterozygosity were low. The proportion of gene diversity of the species within populations (H s) was also low. These indices all indicate that genetic diversity was low within the populations. The inbreeding coefficient within a population, Fis, was significantly larger than expected in each local population. A comparison between Hs and the proportional gene diversity of the species among populations (Dst) showed that almost all variations occurred among populations. Large genetic differentiation was also supported by the high value of gene diversity between populations relative to the combined populations (Gst). Nymphoides coreana is considered to be a selfing species, and genetic variations among the populations were shown to be distinct. © 2008 The Authors.