Lack of allozyme and ISSR variation in the rare endemic tree species, Berchemia berchemiaefolia (Rhamnaceae) in Korea

Abstract

Rare plant species are commonly hypothesized to have little genetic variation because of genetic drift, strong and directional selection toward genetic uniformity in a limited number of environments, inbreeding depression and/or other factors. We investigated genetic variation in Berchemia berchemiafolia, a rare and endangered tree species worldwide, by examining 14 allozyme loci and 28 I-SSR amplicons in 111 individuals distributed among four populations in Korea. No allozyme and I-SSR variation were detected with the exception of one variant from one individual at Pgi-2 locus. A substantial genetic bottleneck accompanying the fluctuation of local population size caused by repeated human activities and inbreeding could account for this species' lack of genetic variation.