EFFECT OF TEMPERATURE AND DESICCATION ON THE PHOTOSYNTHETIC PERFORMANCE OF PORPHYRA PERFORATA

• Published in: Journal of phycology Vol. 36; no. s3; p. 10
• Main Authors: Cabello-Pasini, A., Diaz-Martín, Muñiz-Salazar, R., Zertuche-Gonzalez, J.A., Pacheco-Ruiz, I.
• Format: Journal Article
• Language: English
• Published: Boston, MA, USA Blackwell Science Inc 01-12-2000
• Subjects: Porphyra perforata
• ISSN: 0022-3646; 1529-8817
• DOI: 10.1046/j.1529-8817.1999.00001-28.x

Porphyra perforata is a common seaweed inhabiting the upper intertidal zone, and as a consequence it experiences great fluctuations in tissue temperature and desiccation. The objective of this work was to evaluate the effect of ambient temperature and the tissue desiccation status on the photosynthetic performance of P. perforata. Photosynthetic performance was evaluated polarographically after the temperature or desiccation treatments. Maximum photosynthesis (Pmax) occurred between 25 and 30° C and decreased at higher and lower temperatures, however, no significant differences were observed in the initial slope of photosynthesis (α) from 10 to 30° C. This suggests that the photosynthetic efficiency of this species does not decrease as a result of fluctuating temperatures during tidal emergence/submergence. Pmax and α were relatively constant in tissue of P. perforata with 5 to 100% relative water content. This also suggests that natural desiccation rates during low tides do not decrease photosynthetic rates in this species. Variations in the synthesis of specific proteins as a result of fluctuations in temperature and relative water content in the tissue of P. perforata are being studied.