The Italian region of Puglia has been badly affected by the disease Xylella Fastidiosa over the past few years, the disease is a bacterial infection with many sub species and strains which is found in mainland Europe, most notably France and Italy. The disease is thought to have originated in central America and Xylella fastidiosa is considered one of the most dangerous plant bacteria in the world, a threat not only to olive trees but to a wide variety of other crops such as almonds and vines.
There have been several outbreaks of different sub-species which have led to significant impacts on plants both in the wider environment and those grown commercially for olive production.
In Puglia in southern Italy the outbreak of this disease has lead to the death of many thousands of olive trees most notably in the area around the city of Lecce.
In 2016 Xylella was detected in Spain for the first time on cherry trees in a nursery on the Balearic Islands. It was found for the first time on mainland Spain in 2017, in almond trees. Although EU regulated, there remains some concern about the risk of introduction of the disease to other European countries via infected host plants which might be imported as young plants, and this is considered to be the most likely pathway for entry. The disease is spread by insects that feed on the xylem fluid, that is the vessel of the plant which carries water. This includes the widespread and common meadow spittlebug, which is the principle insect spreading the disease in Italy and France.
Eradication measures for Xylella in the event of an outbreak have been set out in emergency EU legislation. When Xylella is detected in an outbreak situation, all hosts within 100 metres must be destroyed and the area treated to control the vectors. There will also be measures placed on businesses trading in host plants within 5 km. The implementation of these measures would lead to environmental and social impacts.
Puglia’s regional government has recently issued the call for commercial olive growers to apply pesticides two times between May and August to kill the meadow Spittlebug adults which are vectors of the disease. The strong insecticides contain acetamiprid or deltametrina and are not allowed on organic farms which are being allowed to use other products to combat the deadly disease.
The new method of treatment being put forward is the latest drastic step to control the devastating disease blamed for the death of thousands of olive trees in the southern Italian region of Puglia, where Xylella was only first found five years ago.
But organic farmers and environmentalists are outraged at the new mandate, which is viewed as yet another badly thought out policy on how to deal with the spread of Xylella, a fatal bacterium for olive trees native to Central America.