Walnut Disease and Pest Control

Kaolin Application
Kaolin Application: In recent years, Kaolin clay (white clay used in the production of porcelain) has been used in fruit production as a protection against bird damage and various diseases and pests. At the beginning of June, with the dose of 20kg / 1000 Lt, fruits are protected against sunburn and great benefit against harmful insects is obtained.
Bacterial Cancer and Adhessive Ilness in Hard core Fruit Trees.   (Pseudomonas syringae pv. Syringae)
Disease Symptoms
            Bacteria lives in the shell tissue that at the sides of cancerous parts over the winter.
            In the spring, the bacteria begin to multiply in these cancerous parts and spread to the flowers and young leaves with rain.
            It enters the plant from cracks in blooming parts and wounds in the pruned branches.
            Small, oil green, yellowish, purplish, brown spots occur on the leaves with in the time. These stains dry up and fall over time. Leaves take a drilled appearance as if shooted with gun.
            Leaves on the ends of cancerous branches may wilt and die in late spring and summer.
            Diseased flowers wilt and take the color of brown and remain suspended on the branch.
            Diseased buds take brownish color and dry. On the slim branches and buds, brunette spots, deep stains are seen and large numbers of stains lead to drying of the branch.
            Cancers occur on the main branches and the body. Cancer progresses too fast in the spring. The surface of the cancerous tissues is wet and burnt. Sticyy substance output is observed from these parts. Small, slightly sunken brown spots may occur in the fruit.
Fighting Methods (Cultural Measures)
             Healthy seedlings and eyes should be used in the production of seedlings.
            Heavily sick trees should be disassembled and burned.
            Trees that have dried or have symptoms and cancers on the body should be cut off and burned in autumn before spraying.
• The tools used for pruning should be disinfected by immersion in 10% bleach each time
Walnut Antraknosis Disease (Gnomonia leptostyla)
Disease Symptoms
             Disease affects the walnut trees leaflets, fruits, young shoots and leaves.
              Although it is mostly leaf and leaflet disease, if the fruits are deeply effected, the disease may pass into the fruit from the green bark of the fruits and that kinds of fruits quickly decay during the storage.
             Disease cause spots on the leaf in the middle of the growing period of the leaflets. Discoloration occurs in stained places. Then these parts are surrounded by a yellowish halo. The middle of the stain turn into brown color. These stains combine over time to cover a certain part or all of the leaflet. Such trees shed their leaves early.
When the stained part of the fruit is removed, dark spots also are seen on the hard shells. Such fruits quickly decompose during storage.
In the years when the cold burns the first leaves in the spring the appearance of the first symptoms will be delayed and the amounts will be less.
Disease adversely affects the growth of bud and fruit in the coming years and causes a low yield. 
Fighting Methods Cultural Measures
              The fallen leaves should be collected in autumn and buried or deeply buried. The branches, that have the symptoms of the disease and deeply wounds in the previous years, should be pruned to.
Chemical Protection and Disinfection Times
1.           Disinfection: In the period when the buds begin to burst and  the leaves are as big as cat ears,
2.           Disinfection: At the time when the leaves had half size,
3.           Disinfection: In the period when the fruits have taken the size of the hazelnut,
Fourth and other disinfectios should be done in line with the meteorological conditions and the effect period of the used drug.
Walnut Bacterial blight (Xanthomonas arboricola)
Disease Symptoms:
The first symptoms of the disease are seen on the leaves. The disease spreads  all over the leaf and brown-black spots are formed. Bu These stains are transformed into 2-3 mm marginal stains, which are limited to veins from a small point size. Numerous stains and line-shaped formations completely cover the leaf surface and cause deformations in the leaf.
             Young shoots are more affected by disease. Sometimes death occurs at the end of the shoot. In general, during the shooting period different sizes of wounds occurs and this covers the bud. These wounds that surround the shoot are superficial or reach to the core to form a cancer. Bacterial discharge, that not visible to the naked eye, occurs from cancerous parts in humid weather.
             Especially after early spring frosts, signs of burn in the green shoots and buds are very characteristic. If the walnut is still infected during the sapling period, it can completely dry and die. In older trees, the disease causes dryness in young shoots.
Flowers are darkened and dry in the infected plant.
             Fruits are very sensitive at the beginning of their formation. On the fruit surface, there are small, initially fat green, later blackened and slightly sunken spots are seen. Over time, these spots become widespread and cause decay. The stains on the fruit are not confined to the shell, but are spread on the inside of the walnut. The color of the walnut changes and the taste becomes bitter. If the disease is seen when the fruits are small a significant amount of fruit dump occur.
• It is seen in the walnut cultivated areas especially in the Marmara region.
Fighting  Methods:
Cultural Measures

            The diseased shoots and branches should be destroyed by cutting.
            Early discharged diseased fruit should be collected and disposed of.
            Fertilization should be done according to the results of leaf and soil analysis and excessive nitrogen fertilization should be avoided.
            Pruning should be done to ensure air circulation. 
Chemical Fighting:
             The first spraying is started in the burst period of the leaf buds and the duration of the drug used is continued until the conditions of the disease are eliminated.