Mutation breeding in the marine crop Porphyra yezoensis (Bangiales, Rhodophyta): Cultivation experiment of the artificial red mutant isolated by heavy-ion beam mutagenesis

We carried out a cultivation experiment using an artificial red mutant of Porphyra yezoensis isolated by heavy-ion beam mutagenesis to evaluate whether the red mutant has potential as a new cultivar. The blade length of the red mutant was shorter than that of a wild-type HG-511 at the first harvest. However, the results of the present study suggest that the red mutant tends to increase the contents of phycoerythrin, total free amino acid (FAA), alanine and taurine in comparison with the wild type. These tendencies toward the FAA contents were strongly supported by the laboratory culture experiment. From these superior characteristics of pigment and FAA contents, the red mutant IBY-R1 may become a new cultivar in nori cultivation, although it is possible that the mutant harvest will be lower than that of other cultivars.