Endophytic fungal communities isolated from two genotypes of feijoa fruits (Feijoa sellowiana O. Berg.) and prospection of potential agents against anthracnose pathogens
Feijoa sellowiana (O. Berg) Burret is a tropical fruit from South America known as pineapple-guava or feijoa.
Anthracnose is a fungal-caused disease that harms feijoa, and may completely reduce fruit production. The
endophytic microbiota of feijoa fruits from native cultivars may provide new biocontrol agents against
anthracnose. This work aimed to evaluate the diversity of endophytic cultivable fungi in feijoa fruits from two
Brazilian native cultivars and verify potential agents against anthracnose pathogens: Colletotrichum nymphaeae
and Colletotrichum siamense. The cultivable fungal diversity in feijoa fruits was assessed by fungi isolation, followed
by fungal identification, through sequencing the ITS region of rDNA, and estimation of species abundance
and frequency. Later, the antagonism of selected isolates was tested against Colletotrichum spp. by direct
confrontation. Results demonstrated that isolated fungal communities slightly differed between the two cultivars.
There was no difference in the Shannon index between the two cultivars. However, abundance and frequency of
endophytes was respectively, 40% and 53% higher in the most resistant cultivar (Mattos), where Trichoderma
harzianum, Trichoderma hamatum, Clonostachys rosea and Clonostachys rhizophaga were exclusively found. C. rosea
and T. harzianum from cultivar ’Mattos’, and Talaromices amestolkiae found in both cultivars (’Mattos’ and
’Alcantara’), reduced mycelial growth and sporulation of Colletotrichum spp. Therefore, the endophytic cultivable
community was slightly more abundant and rich in the most resistant cultivar of feijoa by encompassing more
antagonistic species of fungi. This work also described for the first time the potential of endophytic fungi as
biocontrol agents of feijoa pathogens.
