Assessing genetic diversity of Andrographis paniculata (Burm. f.) Nees, an important medicinal plant of Thailand using RAPD markers

Abstract

“Fha-Tha-Laai-Joan” ( Andrographis paniculata (Burm. f.) Nees is a medicinal plant widely used in Thailand and some other countries for therapeutic valued, but the lack of their genetic information may cause confusion in its utilization. The Randomly Amplified Polymorphic DNA (RAPD) markers were used to identify and elucidate the phylogenetic relationships among 58 accessions of A. paniculata collected throughout Thailand. Of thirty random primers tested, only eight primers generated a total of 66 bands, of which 26 bands were polymorphic, with an average of 10.5 bands per primer pair. Polymorphic information content (PIC) ranging from 0.034 to 0.405 with an average of 0.172 and 77.59% of A. paniculata accessions showed low PIC scores in a range between 0.00-0.068, indicating low diversity in these accessions. An effective number of allele per locus ( n e ) as 1.018 and very low expected heterozygosity ( H e ), with 0.21 were detected. Genetic similarities of 66 RAPD profiles were estimated via the Jaccard’s coefficient and then the data were processed using UPGMA clustering method. The phylogenetic tree derived from RAPD data revealed that A. paniculata were divided into only one group in which the high similarity values were between 0.81-1.00. The results obtained can be indicated that the distributions of A. paniculata among each region are likely to belong to the same variety and are relatively undifferentiated across a large geographic range.