DNA BARCODING AND MOLECULAR SYSTEMATICS OF SELECTED SPECIES OF FAMILY ACANTHACEAE

In the present study the phylogeny of the various selected genera of Acanthaceae was investigated based on macro-morphological characters, chloroplast DNA (cp-DNA) genes rbcL, matK and intergenic spacer trnH-psbA sequences. About 34 macro-morphological characters of taxonomic importance were selected from the different floras of the world which were used to construct a phylogeny based on morphology. For morphological analysis selected species belonging to five different genera of Acanthaceae including Ruellia, Justicia, Barleria, Dicliptera and Strobilanthes were studied. The phylogenetic tree was constructed using Multivariate Statistical Package (MVSP 3.1) by the method of UPGMA (Unweighted Pair Group Method Analysis). Our results showed that Ruellia brittoniana seemed to be the closest relative of Justicia and Barleria species based on morphological analysis. The plastid gene regions ribulose-1,5-bisphosphatecarboxylase/oxygenase (rbcL), maturase kinase (matK) and trnH-psbA intergenic spacer region were selected for taxonomic study on molecular level. These genes rbcL (1400 bp), matK (800 bp) and trnH-psbA spacer (400 bp) were sequenced and the sequence data was aligned and used for the phylogenetic tree in combination with the other sequences retrieved from GenBank, National Centre of Biotechnology Information (NCBI). Molecular data based on these matK, rbcL and trnH-psbA sequences and the BLAST result shows that genera Barleria, Strobilanthes and Ruellia are monophyletic but genus Justicia is non-monophyletic. Our results conclude that rbcL is more effective barcode; while combination of matK and trnH-psbA can be used for identification and phylogenetic study of plants.