GENETIC BREEDING AND SEEDLING RAISING EXPERIMENTS WITH PORPHYRA PROTOPLASTS

Genetic breeding and seedling raising experiments were carried out with enzymatically isolated protoplasts from vegetative cells of Porphyra. The genetic differentiation and development patterns of cells from different growth stages and different parts of the blade were studied. Several morphological mutants and pure lines were obtained after UV irradiation and colchicine treatment. Polyethylene glycol (PEG) induced interspecific protoplast fusion between P. yezoensis and P. haitanesis. The hybrid cells divided and for-med callus-like cell masses, but no blade differentiation was observed. For cultivation in the sea, the protoplasts and individual cells were attached to nylon rope nets as if they were seeds. Commercial products have already been harvested from these cultivations. This technique omitted the whole process of filament culture, used manpower sparingly, and reduced production costs. It is expected that this technique might be adopted to replace the conventional cultivation method, especially the raising of Porphyra seedlings, in the near future.