Fine-scale spatial genetic and clonal structure of Eleutherococcus senticosus populations in South Korea

Abstract

For the conservation of clonal plant species, better understanding is required of the clonal recruitment process and the spatial distribution pattern of ramets and genets, especially when selecting individuals for ex situ conservation. Because of deforestation and illegal harvesting in natural populations of eleuthero (Eleutherococcus senticosus), a constant conservation effort is needed. We investigated the clonality and spatial genetic structure of two populations located in Hongcheon and Inje using 30 polymorphic markers generated by RAPD or ISSR PCR. The averages of the clonal diversity and genotypic evenness using the multilocus genotypes were 0.961 and 0.880, respectively. These were a little higher than those that have been estimated for other clonal plant species. By spatial autocorrelation analysis, the ramets in Hongcheon were randomly distributed and genetically homogeneous within a meter, while those in Inje showed slight regularity in their distribution and non-genetic patchiness. The average clone size was larger in Hongcheon, but the clonal diversity was opposite. The differences of clonality and spatial structure in both populations might be caused by the distribution of rocks in the forest floor acting as a physical barrier against rooting. There was a mild soil with small pebbles in Hongcheon, whereas the forest floor habitat in Inje was rocky. The clonality and the spatial genetic structure could be easily estimated with information on “putative” clones, verified from molecular work. The clonal recruitment process and sampling strategy for the ex situ conservation of eleuthero are also discussed.