Endophytic fungi were isolated from nine plant species growing
on gypsum
and saline soils in central Spain. The plants sampled
were Arundo donax, Atriplex halimus, Diplotaxis erucoides,
Ephedra nebrodensis, Phragmites australis, Rosmarinus
officinalis, Scirpus holoschoenus, S. maritimus
and Stipa
tenacissima. A total of 152 fungal species were recovered from 2880
samples of leaves,
stems or twigs, taken from 45 individual plants. Ephedra and
Rosmarinus showed the highest diversity of endophytes, whereas
both species of
Scirpus showed the lowest. The most frequently isolated fungi
were
Alternaria alternata, Sporormiella intermedia, Rhizoctonia
sp.,
Epicoccum purpurascens, Pleospora herbarum, Cladosporium
herbarum, Sporormiella australis and a sterile fungus. A
total of 187 strains
belonging to 136 species were tested for the production of antimicrobial
activities,
using a panel of bacteria and yeasts, some of
them of clinical relevance. Production of antimicrobial compounds was detected
in 45 strains, belonging to 37 species. Large
differences were observed among isolates from the same species, with respect
to
their ability to produce metabolites with antimicrobial activity.