Effects of Different Concentrations of Nitrogen and Phosphate on Growth of Sargassum thunbergii Germlings (Phaephyta)

Abstract

In the present study, the germlings shortly released from fertile thalli of S. thunbergii were collected and cultured in the laboratory. The stress resistances of germlings to adverse conditions of different nutrient concentrations and N:P ratios on growth of germingling sporophyte and rizoids were analyzed. Results showed that different concentrations of nitrogen and phosphate could significanly affect the relative grwoth rate and the most obvious growth inhibition was observed in group I which stood for the heavily eutrophicated nutrient condition. Moreover, the negative nutrient condition exerted more serious inhibition on germling sporophyte compared to that on the rizoid, and this might be a suvival strategy for the sustainability of S. thunbergii population.