The sporophylls were cleaned with sterilized seawater to remove debris, other algae, and small invertebrates. Clean sporophylls were kept out of the water in plastic trays in low light conditions (approx. 10 μmol photons m−2 s−1) for about 2 to 3 h. After this, ten sporophylls were placed into plastic trays with 1,000 mL of sterilized seawater for 1 h. Small aliquots were taken to estimate zoospore concentration by means of a Neubauer hemocytometer, and the final concentrations were adjusted to 30.000 zoospores mL−1. Zoospore suspension was decanted through a funnel in order to remove any impurities, and it was used for in vitro cultivation.