Regeneration and Maturation Induction for the Free-living Gametophytes of Ecklonia cava Kjellman (Laminariales, Phaeophyta)

Induction of regeneration and maturation for the free-living gametophytes of Ecklonia cava Kjellman was conducted under various temperature, irradiance and photoperiod conditions. Culture conditions for female or male gametophyte fragments were 4 temperature (5, 10, 15 and 20∘C ), 4 irradiance (5, 10, 20 and 40μmol·m⁻²·s⁻¹ ) and 3 photoperiod (14:10, 12:12 and 10:14 h L:D). Female and male gametophyte fragments were maintained in active regeneration without reaching sexual maturity under 5~10∘C , 5~10μmol·m-2·s-1 , 12:12h or 10:14h (L:D) and 15-20∘C , 20-40μmol·m⁻²·s⁻¹ , 14:10h (L:D), respectively. Sexual maturation of female and male gametophytes facilitated under 15∘C , 20-40μmol·m⁻²·s⁻¹ , 14:10h (L:D) and 5-10∘C , 5-10μmol·m⁻²·s⁻¹ , 10:14h (L:D), respectively. These results provide basic informations to control the regeneration or maturation of the free-living gametophytes for artificial seed production of E. cava.