title: Red light represses the photophysiology of the scleractinian coral Stylophora pistillata.
abstract: Light spectrum plays a key role in the biology of symbiotic corals, with blue light resulting in higher coral growth, zooxanthellae density, chlorophyll a content and photosynthesis rates as compared to red light. However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed. This study investigated the individual and combined effects of blue and red light on the health, zooxanthellae density, photophysiology and colouration of the scleractinian coral Stylophora pistillata over 6 weeks. Coral fragments were exposed to blue, red, and combined 50/50% blue red light, at two irradiance levels (128 and 256 μmol m(-2) s(-1)). Light spectrum affected the health/survival, zooxanthellae density, and NDVI (a proxy for chlorophyll a content) of S. pistillata. Blue light resulted in highest survival rates, whereas red light resulted in low survival at 256 μmol m(-2) s(-1). Blue light also resulted in higher zooxanthellae densities compared to red light at 256 μmol m(-2) s(-1), and a higher NDVI compared to red and combined blue red light. Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI.
authors.affiliation: Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands.
authors.forename: Tim
authors.initials: T
authors.lastname: Wijgerde
authors.affiliation: Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands.
authors.forename: Anne
authors.initials: A
authors.lastname: van Melis
authors.affiliation: Biological Oceanography, Royal Netherlands Institute for Sea Research, 't Horntje, The Netherlands.
authors.forename: Catarina I F
authors.initials: CI
authors.lastname: Silva
authors.affiliation: Departamento de Biologia & CESAM, Universidade de Aveiro, Aveiro, Portugal; Skidaway Institute of Oceanography, University of Georgia, Savannah, Georgia, United States of America.
authors.forename: Miguel C
authors.initials: MC
authors.lastname: Leal
authors.affiliation: Philips Lighting, BG Light Sources & Electronics LED Platform Development, Eindhoven, The Netherlands.
authors.forename: Luc
authors.initials: L
authors.lastname: Vogels
authors.affiliation: Philips Lighting, BG Light Sources & Electronics LED Platform Development, Eindhoven, The Netherlands.
authors.forename: Claudia
authors.initials: C
authors.lastname: Mutter
authors.affiliation: Aquaculture and Fisheries Group, Department of Animal Sciences, Wageningen University and Research centre, Wageningen, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: Osinga
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000502:physiology* / Q000528:radiation effects*; D008027:Light; D010641:Phenotype; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects*