Effect of stocking density and nutrients on the growth and agar gel of Gracilariopsis bailinae (Gracilariales, Rhodophyta)

Abstract

The effect of additional nutrients and varying stocking densities (500, 1000, and 2000 g m^-2) on the growth and physical properties of Gracilariopsis bailinae was determined. Growth was significantly higher (L = 0.05) at a stocking density of 500g both in enriched (3.5%/day) and unenriched (1.9%/day) treatment, but growth was not significantly different between 1000 and 2000g density. A decreasing growth rate was observed with increasing stocking density. Significant differences in gel strength and gelling temperatures were observed only at 2000 g m^-2 both in enriched and unenriched treatment. Results of the study showed that additional nutrients are necessary for the growth of G. bailinae and its agar quality.