Genetic variation and population differentiation of Dorystaechas hastata endemic to Turkey: Implications for conservation management

Dorystaechas hastata is a relict endemic medicinal and aromatic plant under risk of extinction. Assessment of genetic diversity and association between geographic distribution and genetic variation could benefit to the conservation efforts. The objectives of this study were to assess genetic diversity and population differentiation of the species in its natural habitat. The genetic structure of 56 accessions sampled from 15 populations encompassing whole natural distribution of the species were analyzed with both sequencerelated amplified polymorphism (SRAP) and inter-primer binding site (iPBS) molecular markers. The 146 polymorphic markers were generated by 13 SRAP and 11 iPBS primers. The similarity of the accessions ranged from 53% to 91%, with a mean similarity value of 72%. The populations formed two main groups. Principle component analyses (PCoA) and cluster analysis explained 64.9% and 9.4% of the variations with the first and second eigen vectors. The overall genetic diversity of D. hastata was relatively high at the species level, while it is relatively low at the population level. The pairwise allelic differences between populations (F-ST), an indication of population differentiation, ranged from 0.15 (Tunektepe -Hacisekiler) to 0.76 (Altinyaka - Sivridag). The AMOVA results indicated that 51% and 49% of the total variation resided among and within populations, respectively. Geographic distance and/or isolation seem to have strong effect on the genetic differentiation among populations. Results indicate that a representative core collection can be established without significant compromise on genetic diversity. Having the highest genetic diversity Tahtali, Gulluk (Termessos), Beldibi, and Beycik populations must be conserved immediately in nature and might be used to initiate domestication/breeding programs.