Greeks Prepare for the Worst as Xylella Threat Looms

After the recent man­i­fes­ta­tion of Xylella fas­tidiosa at an estate with olive trees on the out­skirts of Madrid that put Spanish author­i­ties on alert, there was another inci­dent in the coun­try, this time in the south, where the bac­terium was iden­ti­fied in a nurs­ery of orna­men­tal plants in Andalusia in mid-April. This was the fourth occur­rence of Xylella in Spain, after the Balearic Islands, the Community of Valencia, and Madrid.
See Also:Xylella fas­tidiosa Articles and Updates
This last case was not rated as dan­ger­ous as the oth­ers since the plants were in a con­tained envi­ron­ment, but cau­tion and pre­ven­tion are always bet­ter than treat­ment. Andalusia is the biggest olive oil-pro­duc­ing region of Spain pro­duc­ing 930,000 tons this sea­son, which trans­lates to almost one-third of global olive oil pro­duc­tion. One can only imag­ine what a dis­as­ter an out­burst of Xylella fas­tidiosa in the area would mean.

Ironically, just in January, the local gov­ern­ment of Andalusia announced that no Xylella case had been iden­ti­fied in the region and an action plan would be enriched with mon­i­tor­ing mea­sures, along with the active pre­ven­tion, sur­veil­lance, and erad­i­ca­tion mea­sures. All these actions would focus on farms, nurs­eries, and other places where plants are grown or sold in Andalusia and are prone to infec­tion by the pathogen, like olive and cit­rus trees, vines, and almonds. Nonetheless, the mea­sures proved to be short on block­ing the entrance to the noto­ri­ous tree killer.

Italy was the first major olive oil-mak­ing coun­try in Europe hit by Xylella in the region of Puglia in 2013 and later in other areas where olive trees are being felled and burned in an attempt to con­tain the bac­terium.

In Greece, where no Xylella case has been offi­cially recorded, the lat­est inci­dents in Spain have set the alarm off for every­one involved.

In Larissa dur­ing a recent phy­tosan­i­tary con­ven­tion, sci­en­tists and agri­cul­tur­ists expressed their fears that the fre­quent imports of plants from Italy pose a sig­nif­i­cant dan­ger, espe­cially when the con­trols at the Greek bor­ders are insuf­fi­cient due to the lack of qual­i­fied per­son­nel, while importers argued that con­trols oppose the rules of open­ness of trade in the European Union.

The sci­en­tists were skep­ti­cal of the alleged resis­tance to the bac­terium olive tree that is attrib­uted to some Italian vari­eties, and they advised the Greek grow­ers not to rush and buy until all eval­u­a­tion pro­ce­dures are com­pleted and the resis­tance of these vari­eties are ver­i­fied.

As the EU has warned, the most com­mon way of Xylella dis­per­sion is by cicada vec­tor insects that fly from one tree to another and carry the bac­terium with them. As these insects are very com­mon inside the entire Union ter­ri­tory, the risk of the pest spread­ing fur­ther is very high. And since the bac­terium lives in the wood tis­sue, any trees or prop­a­ga­tion mate­r­ial that are infected and trans­ferred from one coun­try to another can be the car­rier of the pathogen.

In the mean­time, the author­i­ties of sev­eral olive oil-pro­duc­ing regions of Greece took pre­cau­tion­ary mea­sures to cope with a pos­si­ble inci­dent. In Rethymnon, Crete, the local Office of Agriculture and Veterinary (DAOK) called the farm­ers and grow­ers to act accord­ing to the 2015/789/EU deci­sion of the Union, that spec­i­fies that local author­i­ties must be imme­di­ately informed to exam­ine infected plants and, if the tests are pos­i­tive, then the whole area must be demar­cated at a width of at least 10 km around the prob­lem­atic spot. Plants infected or show­ing symp­toms of a dis­ease caused by the pathogen must be removed.

In Valencia, farm­ers refused to uproot their infected almonds because the state had not spec­i­fied the amount of com­pen­sa­tion they would get, pos­ing another chal­lenge for author­i­ties.

Greece is the only one of the three top olive oil pro­duc­ers in Europe and world­wide still unaf­fected by Xylella fas­tidiosa, but the dan­ger looms near and con­stant vig­i­lance is required to keep the pathogen out.

• Agrotypos.gr