First Report of Nigrospora Species Causing Leaf Spot on Olive (Olea europaea L.)

Leaf spot symptoms were spotted in two olive orchards Istria and Kvarner Gulf, Croatia. Fungal species from three representative isolates (P13 LECIII, R18 BI, JA20 NP) have been morphologically characterized based on the colony conidial characteristics. Several techniques performed for inducing sporulation of NP isolate. Only PDA + banana medium was successful. PCR conducted ITS, TUB, EF1α gene regions. Phylogenetic analyses using internal transcribed spacer, beta-tubulin, translation elongation factor 1-alpha sequence data. Three types tests conducted: a pathogenicity test detached leaves, scratched seedlings. Ultimately, morphological characterizations, DNA analysis regions, phylogenetic analysis, these identified as Nigrospora gorlenkoana Novobr., osmanthi Mei Wang & L. Cai, philosophiae-doctoris M. Raza, Qian Chen Cai. This is first report causing leaf trees plant pathogen. diseases conditions that are favorable infection disease development can lead to decrease yield oil quality. Therefore, it necessary conduct further research monitoring fungal diseases.