In the last five years, we have observed a new decline of Oleaeuropaea in north-western and southern Sicily (insular Italy). Thesyndrome consists in more or less extensive leaf chlorosis, sometimeswith irregular necrotic marginal or apical spots. Apical defoliationof twigs showing cortical necrosis and withering has oftenbeen observed. Isolations, carried out in 2007/08, yilded acomplex of fungal genera associated with the syndrome. Amongthese, Stemphylium sp., a well-known foliar pathogen of otherplants, was constantly isolated from all the alterations observed.In December 2010, single spore colonies of this fungus were usedfor artificial inoculations on healthy 3-year-old olive plants (cv.Biancolilla). Necrotic foliar spots, extending from the inoculumsite to the apex leaf, and twig cortical necrosis with darkening ofinternal tissues were, observed from 15/40 and 90/120 days, respectively,after inoculations. Colonies of Stemphylium sp. werealways re-isolated from all symptomatic organs, thus fulfillingKoch’s postulates. To our knowledge, this is the first report ofStemphylium sp. as a pathogen to olive trees in Sicily. Furthermorphological and molecular studies are in progress to achievespecific identification.
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2011|