Genetic relationships among some species of Dalbergia using PCR based DNA markers

Random amplified polymorphic DNA (RAPD) markers were used to study the genetic relationships among 10 species belonging to 2 sections of the genus Dalbergia. Of the 20 primers initially screened for polymorphism, only 10 amplified genomic DNA across all the 10 species. A total of 224 RAPD bands were observed with an average of 22.4 bands per primer, of which 99% were polymorphic. Pair wise genetic distances were calculated between species according to Jaccard, then used to construct UPGMA dendrogram. Cluster analysis based on the genetic similarities placed 10 species of Dalbergia in 2 clusters, with D. latifolia, D. sissoides, D. horrida and D. melanoxylon in Cluster A, and D. lanceolaria, D. paniculata, D. volubilis, D. rubiginosa, D. malabarica and D. sissoo in cluster B. These 2 clusters corresponds to sections: Sissoa and Dalbergia respectively. The results show that D. paniculata is very closely related to D. lanceolaria and suggested that D. paniculata can be considered as a subspecies of D. lanceolaria. The results of the present investigation distinguished the D. sissoides from D. latifolia, which was considered as a variety of D. latifolia. RAPD data supports the independent species status of the 2 species. The relationship between other species of Dalbergia in each cluster is discussed. This is the first report on genetic relationships among some species of Dalbergia using PCR based DNA markers.