According to Oleorevista, a recent study carried out by Italian researchers describes a set of metabolites that may play a role as markers in Xylella fastidiosa infections in olive trees. The article has been published by the open platform Nature. The research centers involved have been DAFNE, DICATECh, CNR and CIHEAM, linked to the University of Bari.
In the last decade, the bacterial pathogen Xylella fastidiosa has devastated olive trees throughout the Apulia region (southern Italy) in the form of the disease called “Rapid Olive Decline Syndrome” (OQDS). This study describes changes in the metabolic profile due to infection by X. fastidiosa subsp. pauca ST53 in artificially inoculated young olive plants of the susceptible variety Cellina di Nardò.
The test plants, grown in a thermo-conditioned greenhouse, were also co-inoculated with some xylem-inhabiting fungi that are known to occur mainly in trees affected by OQDS, in order to partially reproduce the field conditions in terms of biotic stress.
Investigations were carried out combining NMR spectroscopy and MS spectrometry with an undirected approach for the analysis of leaf extracts. Statistical analysis revealed that Xylella-infected plants were characterized by higher amounts of malic acid, formic acid, mannitol, and sucrose than uninfected Xylella, while slightly lower amounts of oleuropein were revealed. Attention was paid to mannitol, which may play a central role in maintaining olive tree survival against bacterial infection.