We compared delayed fluorescence (DF) excitation spectrometry with radiocarbon (14C) technique using a monoalgal culture of Chlorella vulgaris grown under natural temperature and irradiance. This was done by monitoring the DF, in parallel to quantum efficiency (QE) and index of radiant energy utilization efficiency (Ψ) as calculated on the basis of carbon uptake measurements by radiocarbon technique. During the diurnal cycle, temperature, irradiance, and chlorophyll (Chl) contents were monitored in the algal culture that was kept in an open transparent plastic tank submerged at the surface of Lake Kinneret, Israel. The DF signal correlated with both the QE (r2 = 0.869, p<0.01) and Ψ (r2 = 0.977, p<0.01) during a diurnal cycle. We suggest that, besides the measurement of active Chl and phytoplankton population composition, the DF signal provides additional information on the QE and Ψ in phytoplankton population.
Bibliographical noteFunding Information:
Received 30 January 2007, accepted 28 June 2007. ***Corresponding author; fax: 97246724627, e-mail: firstname.lastname@example.org Acknowledgements: This work was supported by the "Yoachai Ben Nun scholarship" from the Israel Oceanographic and Limnological Research Ltd. Technical assistance by V. Gerhardt and U. Bodemer is gratefully acknowledged. We acknowledge two anonymous reviewers whose remarks helped improving the clarity and quality of the presentation.
- Index of radiant energy utilization efficiency (Ψ)
ASJC Scopus subject areas
- Plant Science