EFEKTIVITAS PENAMBAHAN NUTRIEN DAN MANIPULASI CAHAYA UNTUK MENINGKATKAN PRODUKSI DAN KUALITAS AGAR Gracilaria sp.

Abstract

            Nutrient enrichment and environmental manipulation in this study were aimed to enhance the growth and quality of Gracilaria sp.  Enrichment treatments were  N: P ratio of 10:0 (A), N: P ratio of 10:1 (B), N: P ratio of 5:1 (C) and no nutrient added (D) with stocking density of 800 g per culture media and water depth of 50 cm  in week I-IV. Light manipulation as water depth variation was conducted in week V-VI. Completely randomize design was employed with 6  and 2 replication in week I-IV and week V-VI, respectively.  The results showed no significant effect of treatments on the growth of seaweed (ANOVA, P> 0.05), however DGR maximum indicated by treatment B. The highest water content of the dried Gracilaria <24%, while the average ash content for all treatments <33%. In general, higher agar yields were obtained from non-enriched treatment (D) and treatment with a depth of 80 cm.  

Key words : Disease, enrichment, Gracilaria sp. manipulation, seaweed active extract.