ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Phosphorus-deficient Gracilaria tenuistipitata Zhang et Xia was cultured for 15 days at two different inorganic phosphate (Pi) concentrations: 3 μM (low Pi treatmenl) or 30 μM phosphate (high Pi treatment). The amount of ribulose-l,5-bisphosphate carboxy-lase/oxygenase (Rubisco), phycobiliproteins, Chl a and total soluble proteins were higher in the high Pi than in the low Pi treatment. The total N content of the low Pi plants was lower than in plants grown at high Pi concentrations whereas the amount of total C was highest in low Pi plants. The increase of Rubisco content in the high Pi treatment (3-fold) was parallel to the enhancement of the maximum photosynthetic rate which increased 5-fold. This correspondence was also found in the low Pi treatment in which Rubisco content and maximum photosynthesis did not change significantly from the initial values. The photosynthetic efficiency was also higher at high than at low Pi. The high Pi plants also showed higher dark respiration and growth rates. The data presented here suggest that marine macroalgae submitted to Pi deficiency exhibit a decrease in growth caused not only by Pi implication on energy transfer in photosynthesis and respiration, but also by the diminution of the amount of photosynthetic pigments and Rubisco.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1996.tb00232.x
