Effect of temperature and increased concentration of CO2 on growth and photosynthetic activity of polar alga Trebouxia sp.

• Main Authors: Sehnal, Luděk, Váczi, Peter, Barták, Miloš
• Format: Article in Journal/Newspaper
• Language: English
• Published: Masaryk Univerzity 2014
• Subjects: Trebouxia sp; carbon dioxide; fluorescence of chlorophyll; pigments; Antarctica; lichen; Ross Island; Antarc*; James Ross Island; Usnea antarctica
• Online Access: http://journals.muni.cz/CPR/article/view/12845

Trebouxia sp., a lichen symbiotic alga, was isolated from lichen Usnea antarctica collected at James Ross Island, Antarctica. After isolation, the alga was cultivated on Bold‘s Basal Medium (BBM-agar) with addition of nitrogen for 12 days. Growth of alga and its photosynthetic properties were studied in relation to increased concentration of CO2 (850±50 ppm) and two cultivation temperature (8 and 12°C). Physiological status of algae was evaluated by chlorophyll fluorescence parameters. Simultaneously, content of pigments and changes in biomass were evaluated during cultivation period. Evaluation of physiological state of Trebouxia sp. was carried out after the end of experiment. Results of chlorophyll fluorescence induction parameters and content of pigments showed that the highest efficiency of primary processes of photosynthesis was found at the treatment with elevated concentration of CO2 and temperature 12°C. In this treatment, potential quantum yield of photochemical processes in photosystem II (FV/FM) was 0.44 and content of Chl a was 5.14 µg ml-1. In contrast, the lowest efficiency of primary processes was found at the treatment with addition of CO2 and temperature 8°C, where value of FV/FM reached 0.37 and content of Chl a was 3.71 µg ml-1.