Background: Xylella fastidiosa is a Gram-negative bacterium which lives in the xylem of plants, causing its occlusion and other alterations inducing eventually the death of the infected plants. In Salento, the sub-peninsula in the south-eastern of Apulia Region (southern Italy), the infection of X. fastidiosa has been associated with the widespread presence of CoDiRO (complex of parasitic agents that constitute the so-called "olive quick decline syndrome") and currently represents a serious local emergence. The need to adopt specific agronomic measures to contrast the further disease spread has been recently raised. The extensive NMR-based metabolomic approach to study the metabolic effects of CoDiRO on local olive cultivars such as Ogliarola salentina and Cellina di Nardò was used. Results:In this study, the effects of a CE approved fertilizer containing zinc, copper, and citric acid, known as DENTAMET ® , on CoDiRO-exhibiting olive trees infected by X. fastidiosa were studied by 1 H NMR spectroscopy. The changes in the metabolomic profiles of aqueous extracts obtained from leaves of the two olive cultivars are reported. Upon the DENTAMET ® treatments, different and opposite polyphenolic and sugars patterns in the two cultivars, which showed a different incidence and severity of disease before the treatments, were detected. Conclusions:Differences in the sugars and polyphenols content of treated versus untreated trees could potentially contribute to the syndrome monitoring and might be related to the X. fastidiosa presence.

No abstract