Analysis of the molecular phylogenetics and genetic structure of an invasive alien species, Ricania shantungensis, in Korea

Abstract

An invasive alien species, Ricania shantungensis, has been spreading rapidly since it was first reported in Korea in 2010. Molecular phylogenetic analysis using two sets of nuclear and mitochondrial markers showed that the species was well grouped with the genus Ricania while it was clearly distinct from the genus Pochazia. We conducted haplotype analysis using a total of 215 samples collected from six provinces and found that the Korean populations were composed of eight haplotypes. The haplotype and nucleotide diversity of the samples were 0.544 and 0.005, respectively. The ‘Hap_1’ haplotype occurred at the highest frequency at approximately 65.6%. The genetic distance among the populations ranged from −0.049 to 0.93 and there was no apparent relationship with geographic distance (r2=0.083). The neutrality test detected no rapid population expansion, and a mismatch distribution analysis also supports this finding with a clear multimodal pattern. Instead, severe haplotype decline was detected in almost all of the local populations, which were composed of only 1–3 haplotypes, suggesting the existence of a founder effect. In our UPGMA phylogenetic tree construction, the 12 Korean populations were mainly grouped into four groups that had a significant FSC value (0.446, P<0.001) from AMOVA analysis. In summary, genetic difference was not associated with geographical distance and demographic equilibrium was found with severe haplotype decline. Further analysis is needed to trace its origin and dispersal route to establish a management system for invasive alien pests in Korea.