THE OLIVE oil industry is in a bad way. World output is expected to fall by a third to 2.3m tonnes this year, its lowest level since 2000. The shortfall is largely due to arid weather in Spain, the world’s biggest producer, and

Xylella fastidiosa

, a bacterial disease which is ravaging olive trees in Italy. Production in those countries has fallen by around 50%. To add to these troubles, last week the bug reached Corsica, a French island off the west coast of Italy. The French government has burnt plants near the infected bush to isolate the outbreak, which was previously contained in Southern Italy. But the bacterium is a risk to more than just olive groves in the Mediterranean. Around 300 plant species are vulnerable and it has previously devastated citrus-fruit trees in Brazil and vineyards in California. Olives groves may be only the first casualties.