Note
The main effects and interactions between light (Io, full incident sunlight to 0.07 Io) and NO3− loading (0.4 to 4.3 mmol • g dry weight−1• d−1) on growth rate, photosynthesis and biochemical constituents of Gracilaria tikvahiae McLachlan were studied using a factorial design experiment in outdoor, continuous-flow seawater cultures. Incipient nitrogen limitation in the low NO3− loading, Io and 0.57 Io treatments occurred after 2.5 weeks of growth under the experimental conditions and resulted in decreased tissue NO3− and R-phycoerythrin.