New tests suggest that some varieties of olive trees may be resistant to the invasive pathogen that is harming the trees and the olive industry. Europe’s olive industry has been at serious risk since Xylella fastidoiosa, an invasive bacteria entered in 2013. The bacteria spreads through the roots and branches of the trees and has caused a massive die-out. The invasives were originally introduced to Southern Italy and have now spread to southern France. Luckily, grapes and citrus plants are not affected by the bacteria. However, experts warn that the disease has numerous hosts and vectors and thus spreads more easily. Many are concerned with stopping the disease before it spreads to the world’s largest olive oil producer, Spain. Europe as a whole is the largest producer and consumer of olive oil. According to the European Commission, it produces 73% and consumes 66% of the world’s olive oil. Additionally, recent reports suggest that the outbreak has lead to a 20% increase in olive oil prices in 2015.
However, there is hope! Science! Tests have been conducted on a range of olive, grape, stone-fruit and oak plants to create Xylellea fastidoiosa resistant strains. They have been doing this via artificial inoculation and inoculation via infected vectors collected from the field. The researchers found that 12-14 months after artificially inoculating the bacteria on different olive varieties, some of them were resistant while others exhibited tolerance. In the tolerant species the infection is slower and takes longer for the infection to spread. This shows the potential for different responses to the pathogen in different olive varieties.
The European Commission has provided seven billion euros to investigation like this. Hopefully, further investigation will be as promising and optimistic.