Olive quick decline disease was detected in Europe in 2013 in the Apulia region of southern Italy. This disease is caused by Xylella fastidiosa, responsible for causing multiple diseases in crops of great economic interest such as olive or almond. The pathogen is transmitted by vector insects that feed on the xylem sap and by movement of the infected plant material.
If the necessary measures are not taken to stop the spread of the bacteria, its economic impact in the next half century can be devastating. This is stated by an international team of researchers, with the participation of the Valencian Institute for Agricultural Research (IVIA) and the CSIC Institute of Sustainable Agriculture. Through a study, they have developed a bioeconomic model that analyzes the possible economic impacts of this bacterium on olive trees in Spain, Italy and Greece over the next 50 years.
The study showed through several simulations that, even in the worst-case scenario for the disease, with a slow spread of the bacteria and the possibility of replanting resistant olive trees, the economic impact will be billions of euros. Given this situation, the study highlights that «minimizing the spread of the disease and implementing adaptation measures in the affected areas is more urgent than ever.»
The study indicates that the country with the highest risk of spread, due to its climatic characteristics, is Spain, and warns of a greater danger in the Mediterranean areas of the country. The research simulates several thresholds between now and the next 50 years, according to which the production of olives in Spain could be greatly reduced in places where no action is taken and resistant varieties are not planted.
In the case of Italy, the economic impact may decrease if replanting is carried out with varieties resistant to Xylella.
Currently, there is no effective treatment that allows plants to heal once they are infected, but there are investigations such as the Life Resilience project, where work is being done to obtain varieties resistant to the bacteria and where sustainable agricultural practices are offered that reduce their effect and prevent its implantation in crops.
More information: «Impact of Xylella fastidiosa subspecies pauca in European olives»