Differential xanthophyll cycling and photochemical activity in symbiotic dinoflagellates in multiple locations of three species of Caribbean coral

摘要: Abstract Changes in situ xanthophyll activity were compared symbiotic dinoflagellates within the reef-building corals, Montastraea faveolata, annularis, and Acropora cervicornis over a daily light cycle from morning until dusk on shallow (4 m) patch reef. Examination of algae collected tops sides M. faveolata annularis revealed typical inter-conversion diadinoxanthin diatoxanthin, with greatest abundance diatoxanthin noted by mid-morning to afternoon, correlating reduction effective quantum yield photosystem II (ΔF / Fm′) for respective colony location. A. had highest proportion relative total pool, yet it also displayed least amount cycling which did not correlate well patterns change ΔF / Fm′. For intraspecific comparisons, no significant difference was between different locations each coral species, while differences ΔF / Fm′ detected. In some cases temporal trends nonphotochemical quenching (NPQ) chlorophyll fluorescence match when peak tended lag behind immediate intensity measured at locations. Genetic characterization symbionts using polymerase chain reaction-denaturing gradient electrophoresis rDNA internal transcribed spacer 2 region (ITS2) that hosted type B1 symbiont all locations, A3 throughout cervicornis. Results indicate appears be largely ubiquitous phenomenon dinoflagellates, degree can quite species same depth other biochemical pathways photoprotection may predominate host–symbiont combinations.