Effect of Exposure in Air and Specific Gravity Change of Seawater on Growth of the Sporelings of Porphyra

Abstract

In order to cultivate the healthy sporelings of Porphyra by controlling exporsure to air in noni cultivation ground around esturaris, relationship between growth of the sporelings and exporsing hours in air, resistance to freshwater, influence of seawater specific gravity immersed it before and after the exposure were experimented. The results obtained are as follow;
1) While damage to sporelings caused by drying was lighter in one hour, it became heavier as time got longer, and following to elapse of days.
2) When sporelings was immersed into freshwater influence started arising after 30 h immersion, and all sporelings was withered in 72 h immersion.
3) Damage to sporelings started arising when it was immersed into seawater prior to drying at specific gravity of 1.015, and damage became significant at 1.012.
4) Of seawater specific gravity it was immersed before and after, influence of seawater gravity to be immersed prior to drying was extremely heavier than the other.
5) Growth of sporelings was more effective when immersed into seawater before and after drvincz at little lower side of normal seawater specific gravity of 1.024.