ATHENS – Hopes by Greek olive oil producers for a big crop and prices passing 4.50 euros ($4.81) per kilogram of the extra virgin quality are being jolted by the threat of the olive fruit fly.

The insect was proliferating in some areas of the country during the summer that led to crop-dusting operations, especially in parts of Crete and the Peloponnese on the mainland, two of the prime growing areas, said Olive Oil Times.

In the region of Ilia in western Peloponnese, the fly has been detected primarily in coastal producing areas and small olive groves, according to the local department of agriculture, the report added.

That was believed because of a combination of temperature and humidity prevailing in the area and brought a warning to producers to take measures to protect their expected bounty.

Greece exports nearly $39 million worth of olive oil, ranking it third in the world, but most of that goes to Italy, which re-brands it as Italian and Greek producers don’t market their own brands worldwide aggressively.

On the island of Lesbos, a meeting of local producers, agronomists and representatives of the local administration on the fruit fly control program couldn’t decide how to handle the fruit fly threat, the site said.

According to the producers there, around 40 percent of olives have been lost from the island’s olive trees this year due to extended fruit fly infestation but agronomists argued that almost a third of the island’s olive trees are of advanced age and should be renewed to become resistant to illnesses.

On Crete, where a bumper crop of more than 100,000 tons of olive oil is expected this year, the lack of workers has resulted in the olives being more susceptible to attack by the fruit fly since the fruits remain exposed on the trees longer than usual.

“As the harvest unfolds, we see the worms (from the fruit fly breeding) left on the tractor trailers when the producers transfer their olives to the mill for processing,” Yiannis Koukakis, a miller based near Chania told the site.

In the nearby district of Apokoronas, producers were urged to harvest their olives as soon as possible to avoid any severe impact of the fruit fly on the quality and quantity of the produced olive oil.

The association of Cretan agronomists noted that the fly has become immune to existing pesticides and asked the agriculture ministry to make new pesticides available to producers on Crete and across the country.

“The fight against the olive fruit fly is facing many difficulties the recent years, mainly due to the withdrawal of previously licensed active substances, but also due to the resistance of the fruit fly to pyrethroid insecticides,” the association wrote in a letter to the ministry.

The expert olive oil taster and consultant Vassilis Frantzolas told Olive Oil Times that in other olive oil-producing European countries, including Spain, Italy and France, olive oil producers receive data in real-time about the existing cultivating conditions, including information about manifestations of the fruit fly and other diseases of the olive tree and directions on how to confront them.

“Even more, the crop-dusting operations against the olive fruit fly in Greece rely on chemical pesticides, a practice which is wrong by default,” he said and that European Union directives aren’t being followed.