Evidence for de novo acquisition of microalgal symbionts by bleached adult corals

In this study we tested whether bleached adult corals can acquire microalgal symbionts (family Symbiodiniaceae) from the environment. We subjected adult fragments of corals (six species) to a chemical bleaching treatment. The bleached corals were then inoculated with a cultured symbiont (a Cladocopium C1acro strain). Genotyping of the symbiont communities before bleaching and after reinoculation was carried out. We found that the fragments of all six coral species acquired the Cladocopium C1acro strain used for inoculation.