MOLECULAR PHYLOGENY OF MANGROVES V - ANALYSIS OF GENOME RELATIONSHIPSIN MANGROVE SPECIES USING RAPD AND RFLP MARKERS

DNA from pooled leaf samples of 11. true major mangrove, three true mi nor mangrove, two mangrove associate, two mangrove parasite, three ter restrial and one cultivated species were isolated for the present stud y. In total, 198 random amplified polymorphic DNAs (RAPDs) and 180 res triction fragment length polymorphism (RFLP) loci were scored by using ten primers and 14 enzyme-probe combinations respectively. The polymo rphism observed for these: markers revealed a high degree of genetic d iversity in mangroves at both inter-specific or inter-generic levels. A dendrogram, constructed after pooling both RAPD and RFLP data, using a similarity index was analysed for genome relationships among these species. The dendrogram showed clustering of all the major mangroves, except for Nypa fruticans (Arecaceae), into one group. All species und er the tribe Rhizophorae formed a subcluster, to which Xylocarpus gran atum was found to be the most closesly related species. The clustering pattern implied that Excoecaria agallocha and Acanthus ilicifolius sh ould be considered as true minor mangroves. The present study also pro vided molecular data favouring the separation of Avicennia spp. from t he Verbenaceae to create a monotypic family the Avicenniaceae. The sep aration of Viscum orientale into the Viscaceae was also favoured.