Genetic diversity and relationships among cultivated and wild accessions of tartary buckwheat (Fagopyrum tataricum Gaertn.) as revealed by RAPD markers

The methodology of sampling and the selection of a proper marker system for the analysis of accessions are major concerns in the evaluation of gene bank material. In our study the RAPD analysis of bulked DNA samples and single seeds DNA was successfully employed to evaluate intra- and inter-population genetic variability of cultivated and wild tartary buckwheat accessions. The bulking approach enabled the distinction of all 40 analysed accessions and their separation into geographically well defined clusters. Three wild populations, two from Sichuan and one from Qinghai, formed a group that was genetically relatively distant from wild populations from Tibet and all cultivated landraces which, on the other hand, exhibited very close relationships. The single seed study that was used after bulked DNA analysis provided detailed information of the genetic variation present within some accessions of special interest. A moderate level of genetic variability was detected between accessions and the variability was partitioned into between- and within-population components. On average, most of the detected variation is present between F. tataricum populations. The genetic and geographic distribution of variability is further discussed. We demonstrated the usefulness of combining bulking and single seed study approaches for the effective evaluation of genetic variability in F. tataricum accessions that could also have wider applicability in the management of plant genetic resources and phylogenetic studies.