Callus formation in seven species of agarophyte marine algae

Callus formation of seven species of the agarophyte marine algae Phyllophora nervosa, Gracilaria verrucosa, Furcellaria fastigiata, ceramium kondoi, Gelidium vagum, Laurencia paniculata, Rhodymenia pertusa was obtained from 1984 to 1986. A new sterile agent, chlorhexidin bigluconate, was used to get axenic explants from the algae thalli. The formation of callus from axenic explants depended on temperature of cultivation. In the case of F. fastigiata and G. vagum it occurred at 12° to 20°C, and with P. nervosa at 18° to 26°C. The exchange of sucrose with mannitol in the culture medium and the addition of some growth regulators stimulated the formation of callus. Mass formation of lumpy and warty extensions was observed in the explants from leaf blades of P. nervosa. The results might be useful for improving the aquaculture of agarophyte marine algae.