Photosynthetic response of the macroalga, Gracilaria lemaneiformis (Rhodophyta), to various N and P levels at different temperatures

Gracilaria lemaneiformis , a commercial red macroalga with multiple uses, was cultivated under different combinations of temperatures (10, 20, and 30°C) and nutrients (seawater and four different levels of enrichment) to determine its photo‐physiological response pattern. O 2 evolution‐based photosynthesis–irradiance ( P – I ) curves and chlorophyll fluorescence‐based polyphasic chlorophyll fluorescence transients (OJIP) curves increased with increasing temperature up to 20–30°C, but were nutrition insensitive. The same responsive patterns were followed by their corresponding derived specific photosynthetic parameters. The high photosynthetic tolerance of G. lemaneiformis to nutrient‐loaded stress at a wide range of temperatures, makes it a potential candidate for bioremediating eutrophic mariculture zones.