Over the last few years, farmers from north and central Greece have to deal with a persistent fungal plant pathogen called Spilocaea oleaginea. It is the cause of the olive peacock spot disease, also known as olive leaf spot and bird’s eye spot. Agrotypos contacted Mr. Anthonios Yfoulis, the officer of Quality Control Regional Center of Plant in north Greece, the agronomist Mr. Manolis Grivas and Mr. Fotis Glarakis the Chairman of the Agricultural Cooperatives Union of Chalkidiki. According to them green olives that come from varieties of Chondrolia in Chalkidiki, are sensitive to leaf spot and face very serious problem due to this fungus. Moreover, they reported as major causes of this olive tree disease the mild winter and high humidity of their region. Mr. Sotiris Manakis, the Agronomist of Agricultural Cooperative Union of Agrinio, noted that this region has been suffering for three years from the fungus and also mentioned ways to reduce this problem.
Mild winter and high moisture affect green olives in northern Greek Areas
“Farmers prefer the “green olive” variety cultivation and that’s why they increase their plantations” said Mr. Yfoulis to Agrotypos. And he added “A common problem is that farmers make new olive plantations in areas knowing in advance that they will face problems with the leaf spot. For example they use lands near rivers which have high humidity or sunless places and as a result the trees are infected. From a personal point of view this year in our area fungus didn’t hibernate because of the mild winter, so it was easier to be reactivated and infect our trees. In fact, tempratures between 12-15 º C are ideal for leaf spot fungus. This kind of conditions is something ordinary here. In the next few days we expect such kind of conditions, so farmers in northern Greece have to be very careful. The fungus is not active at summertime. Many Greek farmers may notice symptoms to their trees in August but the fungus already existed from March. So we don’t have to wait until we notice symptoms in our trees because then it will be too late. For example we take samples on a weekly basis from several northern Greek regions. We also have modern meteorological stations that incorporate the predictive models of diseases. These models let us know when the ideal conditions exist for a disease in order to thrive. Then we combine these results with those of our samplings and finally we give the notifications to the farmers”.
The Chairman of the Agricultural Cooperatives Union of Chalkidiki Mr. Fotis Glarakis mentioned to Agrotypos “leafspot causes severe problems as a result of the weather conditions exist at this period of the year”. He suggested preventive spraying with the appropriate fungicides in order to be a step ahead of the disease. Mr. Manolis Grivas also mentioned that the problem with the leaf spot will occur because of the mild winter and high humidity. The “fight” is difficult, since it requires successive copper-containing sprays which are expensive. It is the most expensive spray for the olive culture. In case the variety is “sensitive” it should be sprayed almost every month. Mr. Grivas concluded “The fungicide has an average cost of 50 euros for 0,7-0,8 hectares for each spray so you can calculate how expensive is the total cost for the producer and keep in mind that he might not manage to save his yield. Therefore, many farmers can’t afford it. In order to produce this variety of “green olives” you should cultivate intensively”.
Agrotypos also contacted Mr. Evangelos Evangelinos, the President of the Agricultural Cooperatives Union of Polygyros in Chalkidiki, who said: “The olive peacock spot disease is an issue, it appears to create a serious problem. Later on, when the weather will warm up, in March a clear picture of the problem would be given. A producer having fields nearby rivers, where high humidity exist, is likely to lose his yield”.
Problems in the central Greece
The Agronomist Mr. Sotiris Manakis mentioned to Agrotypos that central Greek has been suffering for three years from olive leaf spot. The mild winter does not allow the fungus to hibernate, so a rain is usually followed by a Spilocaea oleaginea infection of olive trees. Producers should spray with fungicides in February and not be based on copper, which is recommended only for prevention.