Diversity and ecology of culturable marine fungi associated with Posidonia oceanica leaves and their epiphytic algae Dictyota dichotoma and Sphaerococcus coronopifolius

Abstract

Abstract Posidonia oceanica leaves and their epiphytic algae Dictyota dichotoma and Sphaerococcus coronopifolius were sampled to investigate their culturable mycobiota. A total of 102 isolates were obtained; after rejection of duplicates, 32 morphotypes and 27 species were identified using morphological and molecular methods. The highest diversity was observed on P. oceanica with 18 species, followed by D. dichotoma (9 species) and S. coronopifolius (4 species). The phylogenetic analyses suggested the presence of possible new species of Aspergillus, Phaeosphaeria, Preussia and Tamaricicola. The fungal communities detected on the various substrata appeared quite distinct; no species were detected on the three substrata and only four were present on two of them. Strains were investigated for growth preference with respect to salinity and temperature to discriminate marine-from marine-derived fungi. Most strains (90%) were halophiles with a marked euryhalinism, while some (10%) were halotolerant. The majority of isolates had a mesophilic behaviour with some mesophilic-psychrotolerant strains.