海水相对密度对琼枝麒麟菜的生长及其卡拉胶、色素含量的影响

探讨了海水相对密度对琼枝麒麟菜（Betaphycus gelatinum）生长及其色素含量的影响规律。结果表明，海水相对密度为1．016～1．030时，琼枝麒麟菜均可生存，海水相对密度为1．018—1．024时，琼枝麒麟菜生长良好，海水相对密度为1．022时，日生长率高达4．6％，海水相对密度为1．024时，琼枝麒麟菜卡拉胶含量最高，达到64．2％；海水相对密度分别为1．026，1．024，1．022，1．02时，叶绿素a、藻胆蛋白藻蓝素（PC）、藻红素（PE）、别藻蓝素（APC）含量分别达到最大值。

The Effect of Seawater Relative Density on the Growth and the Carrageenan and Pigment Content of the Agar Eucheuma (Betaphycus gelatinum)

Agar Eucheuma （Betaphycus gelatinum）, rich in carrageenan, polysaccharide and various pigments, is an important economic tropical alga. However, production of Eucheuma, both wild and farmed, has become less and less due to the influence of deterioration of seawater environment. Eucheuma growing in different rela- tive densities of seawater were observed and determined in growth rate and content of carrageenan and pigment. Results show that Eucheuma survived at a seawater relative density range of 1. 014 to 1. 030 and grew well at the relative density from 1. 018 to 1. 024. Eucheuma grew at a daily rate of upto 4.6% at the relative density of sea- water of 1. 022, contained 64.2% of carrageenan （the highest among all the treatments） at the seawater relative density of 1. 024, and had maximum contents of chlorophyll a, PC, PE and APC at the respective seawater rela- tive densities of 1. 026, 1. 024,1. 022 and 1. 020. These results give us more insight into the growth characteris- tics of Eucheuma to revitalize farming and development of Eucheuma in the future.