Olive production is one of the main agricultural
activities in Portugal. In the region of Trás-os-Montes, this
crop has been considerably affected by Prays oleae. In
order to evaluate the diversity of fungi on Prays oleae
population of Trás-os-Montes olive orchards, larvae and
pupae of the three annual generations (phyllophagous,
antophagous and carpophagous) were collected and evaluated
for fungal growth on their surface. From the 3,828
larvae and pupae, a high percentage of individuals
exhibited growth of a fungal agent (40.6%), particularly
those from the phyllophagous generation. From all the
moth generations, a total of 43 species from 24 genera were
identified, but the diversity and abundance of fungal species
differed between the three generations. Higher diversity
was found in the carpophagous generation, followed by the
antophagous and phyllophagous generations. The presence
of fungi displaying entomopathogenic features was highest
in the phyllophagous larvae and pupae, with Beauveria
bassiana as the most abundant taxa. The first report of
Beauveria bassiana presence on Prays oleae could open
new strategies for the biocontrol of this major pest in olive
groves since the use of an already adapted species increases
the guarantee of success of a biocontrol approach. The
identification of antagonistic fungi able to control agents
that cause major olive diseases, such as Verticillium
dahliae, will benefit future biological control approaches
for limiting this increasingly spreading pathogen.
