Chloroplast DNA (cpDNA) regions, trnSpsbC and rbcL, from 120 individuals of 24 mangrove and mangrove associate species belonging to 11 orders, 13 families and 17 genera of Angiospermae were amplified by the polymerase chain reaction (PCR) and restriction- digested with HaeIII. Analysis of polymorphism in the restriction fragments (PCR-RFLP) revealed 18 classes of restriction banding pattern in trnS-psbC region. This has provided molecular evidence for diversity in the mangrove floral component at the above-species level. Intra-generic variations were observed in three genera, viz. Rhizophora, Avicennia and Suaeda. Species-specific restriction patterns were found in the genera Rhizophora and Suaeda. A natural hybrid belonging to the genus Rhizophora was also analysed, and its restriction pattern was the same as that of a putative parental species. PCRRFLP analysis of rbcL gene region was less differentiating. However, it showed 13 different classes of restriction patterns and revealed the usefulness of these investigations
for genome analysis at a higher taxonomic level.
Intra-specific variation was not observed in any of the
species in either of the cpDNA regions analysed. This is
the first report which describes variations in the chloroplast
genome of mangrove species.