Genetic relationships and species authentication of Boesenbergia (Zingiberaceae) in Thailand based on AFLP and SSCP analyses

Genetic relationships of 15 Boesenbergia species were examined using AFLP analysis. A total of 893 fragments were generated from six primer combinations; of these, 99.78% were polymorphic. The mean genetic distance between pairs of taxa ranged from 0.435 to 0.935. The neighbor-joining tree resolved investigated species into two separate lineages (corresponding to species possessing compact or elongated inflorescences) and suggests a rapid radiation in Boesenbergia. In addition, SSCP patterns of the partial psbA–trnH spacer were not overlapping between different species and therefore can be used for authentication of Boesenbergia species. Morphologically similar Boesenbergia longiflora and Boesenbergia sp., which showed three SNPs based on psbA–trnH polymorphism were successfully differentiated by SSCP. Moreover, Boesenbergia curtisii displayed intraspecific ecomorphological variation but exhibited the same SSCP pattern. Therefore, AFLP and SSCP are rapid and cost-effective methods for analysis of genetic similarity and species identification in Boesenbergia.