Eucheuma striatum Schmilz was transplanted from the Philippines into the subtropical waters of Tosa Bay, Shikoku Island, Japan. The yearly Variation in temperature of the seawater at the culture site was 10.2 to 31.2 °C, turbidity was 0.1 to 3.7 ppm, and salinity was 31.17%o to 33.86%o. Plants were grown using a monoline method at a depth of ca l .0 m below the water surface. Plants could be grown from May to October, when the seawater temperature ranged from 20.9 to 31.2°C, with a growth rate of 1.4 to 5.9% day" 1 . The most favourable growth period was from August to October. Maximum biomass production, ca 9100% over the initial weight, was obtained after 5.5 months in October. Plants grown at a depth of 2.25 to 3.5 m did not have a significantly different growth rate from the plants grown nearer the surface (0.25 to 2.0 m). Plants produced cystocarps releasing many carpospores in October at temperatures of 21.1 to 24.8 °C.In the laboratory, plants were grown in artificial seawater made from synthetic sea salt 'Jamarin' U and enriched with a fertilizer (Norimax) under ranges of salinity, temperature, Illumination and photoperiod. Maximum growth, äs well äs fruiting, occurred in culture at 24 °C, 6 k lux Illumination, 12: 12h L/D cycle and culture media of 35.11%o salinity.

No abstract

Gelidium pusillum was grown in media of von Stosch, Chen etal. and Schreiber. Von Stosch's medium was found better for the growth. No spores were producted under any photoperiod. The alga showed two vegetative growth phases. The first one was completed within 3 to 4 months. Increase in fresh weight of the alga was best under 20 hr 4 hr light and dark cycle äs well äs continuous Illumination. During the second growth phase, plants separated into a number of small bushlets, more so in the cultures given 8 hr -6 hr light and dark cycle. Fragments of the alga, äs small äs 2 mm in length, can regenerate without any loss in their capacity to produce proliferations. Plants grown in cultures yielded 22% agar having a gel strength of 210 g/cm 2 .

No abstract

No abstract