Coral Reefs

, Volume 28, Issue 1, pp 179–195

Photobiology of Symbiodinium revisited: bio-physical and bio-optical signatures

  • S. J. Hennige
  • D. J. Suggett
  • M. E. Warner
  • K. E. McDougall
  • D. J. Smith
Report

DOI: 10.1007/s00338-008-0444-x

Cite this article as:
Hennige, S.J., Suggett, D.J., Warner, M.E. et al. Coral Reefs (2009) 28: 179. doi:10.1007/s00338-008-0444-x

Abstract

Light is often the most abundant resource within the nutrient-poor waters surrounding coral reefs. Consequently, zooxanthellae (Symbiodinium spp.) must continually photoacclimate to optimise productivity and ensure coral success. In situ coral photobiology is becoming dominated by routine assessments using state-of-the-art non-invasive bio-optical or chlorophyll a fluorescence (bio-physical) techniques. Multiple genetic types of Symbiodinium are now known to exist; however, little focus has been given as to how these types differ in terms of characteristics that are observable using these techniques. Therefore, this investigation aimed to revisit and expand upon a pivotal study by Iglesias-Prieto and Trench (1994) by comparing the photoacclimation characteristics of different Symbiodinium types based on their bio-physical (chlorophyll a fluorescence, reaction centre counts) and bio-optical (optical absorption, pigment concentrations) ‘signatures’. Signatures described here are unique to Symbiodinium type and describe phenotypic responses to set conditions, and hence are not suitable to describe taxonomic structure of in hospiteSymbiodinium communities. In this study, eight Symbiodinium types from clades and sub-clades (A–B, F) were grown under two PFDs (Photon Flux Density) and examined. The photoacclimation response by Symbiodinium was highly variable between algal types for all bio-physical and for many bio-optical measurements; however, a general preference to modifying reaction centre content over effective antennae-absorption was observed. Certain bio-optically derived patterns, such as light absorption, were independent of algal type and, when considered per photosystem, were matched by reaction centre stoichiometry. Only by better understanding genotypic and phenotypic variability between Symbiodinium types can future studies account for the relative taxonomic and physiological contribution by Symbiodinium to coral acclimation.

Keywords

Symbiodinium Fluorescence Photosystem II Pigments Light absorption 

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • S. J. Hennige
    • 1
  • D. J. Suggett
    • 1
  • M. E. Warner
    • 2
  • K. E. McDougall
    • 3
  • D. J. Smith
    • 1
  1. 1.Coral Reef Research Unit, Department of Biological SciencesUniversity of EssexColchesterUK
  2. 2.College of Marine StudiesUniversity of DelawareDelawareUSA
  3. 3.Environmental Research Institute, North Highland CollegeUHI Millennium InstituteThursoUK