Ex Situ Conservation of the Federally Endangered Plant Species<i>Clematis socialis</i>Kral (Ranunculaceae)

Abstract

The Center for Plant Conservation (CPC) has created sampling guidelines for the ex situ conservation of rare plant species. These guidelines estimate the number of individuals needed to maximize the genetic diversity of the collection according to population genetic theory. For many clonal plant species, knowledge of the number of unique individuals is not easily discerned and application of these guidelines must be based on molecular genetic data. In this paper, we discuss the steps taken in order to meet CPC guidelines for the conservation of a rare clonal plant, Clematis socialis. Due to limited seed availability, methods were developed for successful in vitro propagation and cryopreservation of C. socialis shoot tips. Inter-simple sequence repeat (ISSR) analysis identified fifteen unique genotypes in the ex situ in vitro collection. One genotype in this collection has been conserved from a population that is now presumed extinct. Although the initial sampling protocol managed to capture considerable genetic diversity, an additional 97 genotypes are needed to meet CPC guidelines. The information and experience gained through the initial C. socialis ex situ conservation efforts form the basis for a strategy to improve ex situ conservation activities for this endangered species. We recommend that additional in vitro collections be made from each of the five extant populations and placed in cryostorage.