Study identifies for the first time strains of a bacterium that seriously affect various agricultural crops in Portugal
The study traces the introduction of 'Xylella fastidiosa' into Portugal, a bacterial plant pathogen that causes disease with serious impacts on crops such as vines and almonds.
Researchers from the Faculty of Sciences and Technology of the University of Coimbra (FCTUC) have successfully isolated, for the first time in Portugal, several strains of the bacterium Xylella fastidiosa, which is linked to Pierce’s disease and poses a significant risk to Portuguese agriculture.
The study reveals the origin of the bacterium’s introduction and reinforces the need to monitor the disease it causes, which can severely affect crops such as vines and almonds. The European Commission considers Xylella fastidiosa a priority quarantine pest, with an economic impact of more than €5.5 billion per year in the EU.
Since it was first detected in Apulia, Italy, in 2013, the bacterium has been found in nearly twenty delimited areas in Portugal, mainly in the north and centre. A group of researchers from FCTUC have now isolated the ST1 fastidiosa subspecies for the first time in Portugal.
“This study is crucial to understanding the real risk posed by Xylella fastidiosa in Portugal. The ST1 strain, associated with serious disease in vineyards in California, raises concerns for the future of Portuguese crops,” emphasises Joana Costa, coordinator of the XylOut project and researcher at FCTUC. She adds: “The strains were isolated in Cova da Beira, and the genomic results suggest a single introduction of the bacterium, originating in California. The affected plants include both cultivated and wild species, indicating that spontaneous vegetation may act as a reservoir for the bacterium.”
The research was carried out at FITOLAB, the first Portuguese laboratory accredited to detect Xylella fastidiosa. FITOLAB exemplifies the strategic link between FCTUC and IPN, which has enabled the team to overcome the legal and technical barriers associated with the study of this quarantine bacterium and ensure that research advances reach the agricultural sector. The work was conducted as part of Eva Garcia’s PhD (UC Doctoral Programme in Biosciences), in collaboration with the Citriculture Centre of the Agronomic Institute of Campinas (Brazil) and the University of California, Berkeley (USA).
The scientific article Isolation, Phylogenetic Inferences, and Early Diversification of Xylella fastidiosa subsp. fastidiosa in Cova da Beira Region, Portugal was published in the journal Phytopathology and is available here.