European University of Lefke (EUL) Faculty of Agricultural Sciences and Technologies Faculty Member Asst. Prof. Dr. Murat Helvacı gave information about “Methods of Combating Olive Diseases and Pests”.
Stating that there are many diseases and pests that cause economic losses in olive cultivation in the Turkish Republic of Northern Cyprus, Helvacı said that the olive fly, which is the main pest of olives, takes place at the beginning. Helvacı continued his explanations on the subject as follows; When olive fruits start to ripen (oil), the olive fly lays its eggs inside the fruit via the ovipositor, and the egg opens in the fruit and feeds on the fruit flesh. The perforated fruit falls to the ground and in the winter season, the olive fly larva (maggot) is 2-3 cm from the soil. It passes the pupa (sleeping period) under it and emerges to the soil surface in spring. The new adults emerging from the soil spend the period until the fruits start to get oily by feeding on flower nectars, and in this way they continue their life cycle.
Olive fly causes fruit drop and reduced olive oil quality.
“Olive fly causes fruit drop, as well as increasing the acidity of olive oil and causing a decrease in olive oil quality,” said Helvacı, adding that another important pest that causes product loss in olives is olive moth. Stating that the olive moth is an insect that has the potential to cause damage in every period of the olive, and that it causes damage to the flowers during the flowering period, Helvacı continued his explanation as follows; It forms spider web-like structures where the inflorescences are located. This is the most obvious proof of the presence of the olive moth pest. Another pest is the cotton lice pest. The larvae of cotton lice in olives are harmful by absorbing the sap of the plant on the bud stems and shoot tips of the olive inflorescences, weakening the trees and shoots, and causing the shedding of flowers and flower buds. Like other olive pests, it is common in all regions where olives are grown in our country.
Continuing with his words, Helvacı also talked about olive diseases and said; The most common olive diseases in our country are Wilt (Verticillium), Ringed Spot and Olive Branch Cancer. With wilt disease, fungal spores settle in the part known as the vascular bundle in olives and all plants, which plays a role in the transport of water and nutrients, and prevents the clogging of that area and the passage of water and nutrients. Thus, wilting and shedding of the leaves occur. In branch cancer, wounds are opened on the olive branches, especially in the gardens where the harvest is made by hitting the branches, and the disease factor enters through these wounds and forms tumor-like structures on the branches. Burning these branches with deep pruning is seen as the most effective and only control method.
The mixture of apple cider vinegar and sugar is effective against olive fly.
Helvacı said that ring spot disease in olives shows its first symptoms in the form of blackish-gray circular spots, especially on the upper surfaces of the leaves in spring, and it is called ‘ringed spot disease’ because of this ring-shaped appearance, and when the disease progresses, these spots cover the whole leaf and lead to yellowing and shedding of the leaf over time. stated why. “When the disease epidemic (severe contagion-epidemic) it causes severe shedding of leaves and bare trees. The plant, which cannot photosynthesize sufficiently with the loss of leaves, falls in yield because it cannot feed itself. In the fight against this disease, spraying with copper preparations is done after pruning in the winter period after harvest. Since copper is a fungicide used in organic agriculture, its use in the fight against this disease is important in terms of environmental friendliness and not having a negative effect on human health compared to pesticides,” said Helvacı. He stated that it is essential to switch to alternative methods of struggle because they have negative effects on health and other living things. “For this reason, it is necessary to use biological (using beneficial insects to suppress the pest population and biotechnical (using traps) methods of control)” said Helvacı, and lastly, he gave advice to the producers and said; Especially, we put apple cider vinegar+sugar mixture in 1 liter plastic bottles that we use at home. When we put it to fill 1/5 of the bottle and hang it on the sun-exposed parts of the trees, it can be effectively combated against the Olive fly, which is the main pest of olives.Besides, the biological control method gives an effective and lasting result in the long run.Pesticides can have negative effects on the environment and human health. Considering that the number of pesticides used in the fight against olive diseases and pests has decreased, it is inevitable to turn to alternative control methods.