Plant diseases represent a significant threat to global food security. One of the pathogens ranked in the “list of priority pests” for Europe is Xylella fastidiosa. This Gram-negative bacterium is responsible for important re-emerging plant disease, initially discovered in the late 1800’s and causing outbreaks over the past decade around the Mediterranean basin with hot spots in Italy, France and Spain, and more recently in Israel. X. fastidiosa is transmitted via xylem-sap feeding insects, directly delivered into the xylem, where it colonizes the vessels, formed by dead cells, and systematically infects the whole plant.
As a species, X. fastidiosa can infect more than 600 plant species, including crops, forest, herbal and ornamental plants. In hundreds of these species, X. fastidiosa does not cause macroscopic disease symptoms and occurs as an endophyte but in many important crops the bacterium causes some of the most destructive plant bacterial diseases. For example, Xylella fastidiosa is the causal agent of Pierce’s Disease (PD) in grapevine and the Olive Quick Decline Syndrome (OQDS) in olive trees, ultimately it results in tree mortality. Given the lack of disease control by agrochemicals and the devastating threat to olive production, there is an urgent need to develop resistant crop varieties and new, curative/protective pathogen control treatments.
When infected with X. fastidiosa, grapevine, olive and other host species develop macroscopic disease symptoms, yet other infected plant species remain symptomless. The underlying molecular mechanisms, including the interaction of X. fastidiosa with the highly diversified immune systems across plant species remains largely unexplored. MultiX seeks to provide insight into the mechanisms underlying xylem infection of X. fastidiosa, exploring genetic model plants and crops. More strategically, MultiX aims to deliver information that could pave the way for disease control of X. fastidiosa, through genetic elevation of immune receptor capacities in a cell file-dependent manner.