Apple diseasesmay lead to a reduction in the quality and quantity of the yield, the weakening of whole trees, and even their dieback. Therefore,apple disease symptomsshould not be taken lightly. It is worth learning to recognize the individual diseases of apple trees and learn about the methods of combating them. Here are the most commonapple diseases and combating themin allotment and home gardens. Discover the best ways to get he althy apples from your own garden!
Diseases of apple trees. From left to right: scab, fire blight, brown rot
Apple diseases - scab
Apple scab , caused by the fungus Venturia inaequalis, is the most common and quite difficult to control apple disease. Scab mainly affects leaves and fruit. The firstsymptoms of apple scabare visible in mid-May, during the flowering period. Olive, gradually darkening spots appear on the leaves. Then the symptoms are visible on the buds and fruits in the form of irregular, jagged spots on the edges, rough to the touch. Early infested fruits are deformed and fall off the tree.
Apple scab is controlledmainly by chemical means. Agrotechnical procedures, such as removing infected leaves and fruits, are an auxiliary function in the fight against this disease. Pre-flowering copper fungicides such as Miedzian 50 WP (1.5 g in 500-750 ml of water / 10m²), Cuproflow 377.5 SC (20 ml in 8-10 l of water / 100m²) or Cobresal 50 WP (1.5 g in 500-750 ml of water / 10m²).
Autumn spraying of fruit trees with 5% urea solution is also very important. The treatment should be performed just before the leaves fall, when most of them are still on the tree. Whole tree crowns and leaves that have already fallen under the trees are sprayed thoroughly. Spraying fruit trees with urea significantly reduces the risk of spring infection from fallen leaves left for the winter. Thanks to this, we reduce the need to apply subsequent spraying in the spring.
Apple diseases - fire blight
Fire blight is the most dangerousbacterial disease of apple treesIt is caused by Erwinia amylovora bacteria. Fire blight affects all above-ground parts of the tree. The most characteristicsymptoms of this apple diseaseare gangrene of flowers and the characteristic cane-shaped tips of the young shoots. The whole tree looks soothed by fire and dies.
Fire blight is a quarantine diseaseand is ruthlessly combated.Infested shoots should be cut and destroyed. Before flowering, spray the apple trees with Cobresal 50 WP (15 g in 5-7 l of water / 100m²) or during the blooming period with Miedzian 50 WP (15 g in 5-7 l of water / 100m²).
Apple diseases - brown rot
Brown rot of pome treesis a disease caused by the fungus Monilinia fructigena, which often affects apple trees. Symptoms are visible mainly on fruit, less often on flowers. Apples develop brown rot spots, most often where the skin is damaged. On the spots appear, concentric, light beige, dusty warts. The apples rot on the tree and then dry up and turn into black mummies. The mummified fruit does not fall off and remains on the tree for the winter, becoming a source of infection in the following year.
In order toreduce the development of this apple disease , collect and destroy mummies during the winter or spring apple formation.If in the previous season in our orchard there was brown rot of stone trees, we spray the trees with the Syllit 65 WP preparation (10 g in 5-15 l of water per 100 m2). After noticing the symptoms of the disease, spray the apple trees with copper preparations - Miedzian 50 WP (1.5 g in 500-750 ml of water / 100m²), Cobresal Extra 350 SC (1.5 ml in 500-750 ml of water / 100m²).
Apple diseases - powdery mildew
Apple mildewis a very harmful fungal disease. It infects apple trees in orchards and nurseries, inhibiting the growth of shoots and leaves.Symptoms of apple mildeware visible on buds, shoots, leaves and fruits. The most harmful is the infestation of the buds and tips of shoots that die. The developing fruit is covered with a white, powdery coating.
Apple mildew is foughtwith chemical and agrotechnical methods. Prevention of the disease consists in removing the primary source of infection by cutting out infected shoots.It is best to carry out this treatment in spring, immediately before flowering. After noticing the symptoms , fight apple mildew , using chemical preparations from the beginning of the flowering phase or after flowering, such as Kaptan PLUS 71.5 WP (20 g in 6-8 l of water / 100m²) or Siarkol Extra 80 WP (75 g in 6 liters of water / 100m²).
Diseases of apple trees - cancer of fruit trees
Fruit tree cancer , caused by the fungus Nectria galligena, is a common disease of apple trees. It is especially harmful in humid coastal climates.Symptoms of this apple diseaseare cancerous wounds that form on trunks, branches and one-year-old shoots. In sick places, the bark dies and falls off the tree, revealing the wood. A characteristic symptom of fruit tree cancer is the concentric arrangement of the zones of annual growth on the wound around the site of primary infection. Cancer wounds develop over several years, gradually enlarging and deepening.
Currently, there are no preparations to combat the fungus, which is the cause of the disease, soin the fight against apple cancerprevention is the most important.When cutting fruit trees in the early spring, pruning wounds should be treated with a garden ointment containing a fungicide, eg Funaben Plus 03 PA. We remove all infected shoots on which mane spores may be deposited. In spring, during crown formation, we spray the trees prophylactically with Topsin M 500 SC (15 ml in 5-7 l of water / 100m²).
MSc Eng. Agnieszka Lach
