Presence of clade D Zooxanthellae in dominant Sclerectinian and soft corals in Larak island, Persian Gulf

Dominant sclerectinian and soft corals contain the symbiotic single cell called zooxanthellae which have important role in preparing organic material for coral requirements. The coral reefs of this area in the gulf are always under effects of environmental conditions, such as subtropical latitude, temperature and salinity variations, changing symbiotic zooxanthellae. The aims of this study was identification of Symbiodinium clades and presence of clade D in sclerectinian and soft corals of Larak island by molecular methods.

Three soft coral species and five sclerectinian coral species were collected from north and north east of Larak island, respectively. After DNA extraction, partial 28S ribosomal DNA of Symbidinium were amplified by polymerase chain reaction (PCR). Then PCR products were analyzed by phylogenetic analyses of the partial 28S ribosomal sequence.

To follow amplification of 28S large ribosomal subunit gene, the 780 bp PCR products were sequenced and were compared to the gene bank. The results showed that all the symbiotic clades of soft corals in Larak Island belonged to clade D.

Dominance of clade D in sclerectinian and soft corals in Larak island due to of high temperature in the Persian Gulf and unstable condition of Hormoz strait is normal and natural.