Mediterranean oranges risk ‘yellow dragon’ extinction

Known as the “citrus greening”, or “yellow dragon” disease, the illness is spread by an Asian insect that sucks on the tree sap. The problem only becomes apparent when the trees’ leaves begin to go yellow. Then, the fruits become deformed, and the tree dies.

In Florida, one of the USA’s primary orange producing areas, up to 99% of this year’s crop has been affected, with orange production having fallen by 60% between 2005 and 2017, and the price of orange juice doubling to $2,500 (€2,049) per tonne.

Researchers in Europe now say the Mediterranean region could be at similar risk.

Eric Imbert, researcher at Montpellier agricultural centre le Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), told the Agence France-Presse that the illness could cause “a phenomenally fast [negative] impact”.

This could be especially true in areas where fruit trees are grown close to inhabited areas, as the use of pesticides is limited by law.

And, according to figures from specialists FruitTrop, 21% of the oranges, clementines and lemons eaten in the world come from European countries. The same region also controls around 70% of the world’s citrus exports.

Mr Imbert said: “Without wanting to cause panic, if we do not do anything to prevent this, we could have a major catastrophe, seeing prices double or triple” for products such as orange juice and citrus fruits.

He added: “We have been trying to raise the alarm for years, especially when it comes to European authorities, but sometimes it feels like we are shouting into a void.”

The disease is difficult to study - and to find a cure - as it cannot be created in a laboratory, say researchers. So far, no miracle cure to the problem has been found, except in places with high altitude.

In La Réunion, the French island in the Indian Ocean - which was also affected - fruit tree farmers were able to deal with the problem by simply unearthing their trees, and replanting them at a much higher altitude, where the Asian insects carrying the disease were unable to survive.

In the absence of any such solutions in Europe, Mr Imbert said: “We are not immune to a similar phenomenon [to the disaster in Florida] on the small fresh citrus fruit market in the Mediterranean.”