Coral disease physiology: the impact of Acroporid white syndrome on Symbiodinium

• Published in: Coral reefs Vol. 27; no. 2; pp. 373 - 377
• Main Authors: Roff, G., Kvennefors, E. C. E., Ulstrup, K. E., Fine, M., Hoegh-Guldberg, O.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2008; Springer; Springer Nature B.V
• Subjects: Acropora hyacinthus; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Biomedical and Life Sciences; Chlorophyll; Cnidaria. Ctenaria; Coral reefs; Disease; Freshwater & Marine Ecology; Fundamental and applied biological sciences. Psychology; Invertebrates; Lesions; Life Sciences; Marine; Marine ecology; Oceanography; Sea water ecosystems; Symbiodinium; Synecology; Tissues; ISEW, Australia, Queensland, Great Barrier Reef, Heron I., Wistari; ISEW, Australia, Queensland, Great Barrier Reef; Disease; White syndrome; Coral; Monocotyledones; Algae; Hyacinthus; Coral reef; Scleractinia; Syndrome; Coelenterata; Liliaceae; Dinophyta; Angiospermae; Cnidaria; White syndrome .Coral; Spermatophyta; Physiology; Invertebrata; Acropora hyacinthus .Symbiodinium
• ISSN: 0722-4028; 1432-0975
• DOI: 10.1007/s00338-007-0339-2

Acroporid white syndrome, a disease-like syndrome from the Great Barrier Reef, results from degenerative host tissue at lesion borders. Tissue preceding lesion borders appears visually healthy, but it is currently unclear whether the endosymbiotic zooxanthellae ( Symbiodinium ) are physiologically impacted. Compared to healthy colonies, this study found no significant differences in symbiont density, mitotic index or chlorophyll a content in tissue bordering (0 cm), and 8 cm away from white syndrome lesions. Using chlorophyll a fluorescence techniques, the border tissue did not appear to be photosynthetically compromised, and Symbiodinium extracted from this area were photosynthetically competent. Transmission electron microscopy revealed extensive degeneration of host tissues surrounding symbionts in affected areas, however, Symbiodinium cells were structurally intact with no sign of in situ degradation. Collectively, these results suggest that Symbiodinium at white syndrome lesion borders exist in a dynamic intra-cellular state during active host tissue loss, yet remain physiologically uncompromised.