Identification of as Causal Agent of Olive Tree Dieback in Apulia (Southern Italy).

Olive ( L. var. ) is one of the most economically important tree crops grown in the Mediterranean basin. Kunze Fr. (teleomorph: Sacc.) is a widespread fungal genus, and Larrondo & Calvo is a ubiquitous species, found in algae, soil, plants, and agricultural communities. was isolated from olive trees showing dieback from orchards located in Andria and in Fasano, Brindisi (Apulia, southern Italy) and identified based on morphological features and molecular analysis of four genomic regions (ITS, , , and ). Two-year-old olive plants artificially inoculated with three representative isolates showed complete dieback within 6 months, and the fungus was reisolated, satisfying Koch's postulates. This is the first report of causing dieback on olive trees that could represent an important threat for olive cultivation.