Bitter pox wrinkle water heart disease is due to calcium deficiency how to prevent and treat apple calcium deficiency

In recent years, apple bitter pox disease, wrinkled skin, water heart disease, black skin softening symptoms are serious, especially in long-term rainy years before harvest, red spots, black spots are more common, affecting the commodity value of apples. All of them were caused by severe calcium deficiency or climatic factors affecting calcium transport.

Calcium deficiency in apples

Symptoms:

Early bitter pox disease, apple skin is spongy, but not rotten. Red spots and black spots formed before harvest should be distinguished from infectious diseases or physiological diseases. Red and black spots formed by infectious diseases rapidly expand and penetrate into the flesh, causing apple rot. Calcium deficiency formed red spots, black spots, depression dry shrink into black scars but not rot, also known as bitter pox disease. Cut off the epidermis with a knife, such as sponge-like subcutaneous, that is, calcium deficiency symptoms formed during the expansion period of apples. If the hypodermic flesh is normal, it is a calcium deficiency symptom formed during apple ripening. Calcium deficiency apple, storage period is also prone to bitter pox disease, water heart disease, soft black skin and other symptoms.

Reason:

(1) Fertilization of fruit trees, chemical fertilizer, available trace elements in soil are on the verge of depletion, and calcium deficiency is serious. (2) Apply a large amount of nitrogen, phosphorus and potassium fertilizers to inhibit calcium absorption. (3) Severe drought, soil moisture reduced to 50% of the maximum field water holding capacity, leaves wilted, transpiration function weakened, affecting calcium transport. Water logging, calcium and other element deficiencies will occur at the same time. 5. During the rapid expansion period of apples before harvest, there is no light for a long time, which affects calcium transportation and causes calcium deficiency symptoms such as red spots, black spots and black scars.

Prevention measures:

1. Get out of the misunderstanding of fertilizer being the head of the household. Basic fertilizer in autumn, mainly farm manure and high-quality organic fertilizer, 30~40 kg of silicon-calcium fertilizer such as calcium, magnesium, phosphorus and calcium superphosphate shall be applied per mu. By increasing soil organic matter and trace elements, fertility, improve soil calcium content. Because calcium ions are transported slowly in trees, the effect may not be obvious in that year. However, persisting for several years can fundamentally solve the problem of calcium deficiency.

2. Calcium supplementation in soil. March is the early stage of the first growth peak of apple tree roots, and 20~25 kg calcium nitrate is applied every 6 mu.

3. Foliar calcium supplement. In the apple bud period, before flowering, flowering, young fruit period, after de-bag with amino acid calcium 300 times solution or other chelated calcium liquid fertilizer spray 5~6 times, this is a calcium shortcut, that is, effective in the year.

4. Through pruning, the crown bore, lower branches, to create good lighting conditions.

5. In case of drought, water in time. In apple orchards without irrigation conditions, covering grass or storing fertilizer in holes should be carried out to keep 60~70% of the maximum field water holding capacity of soil all the time.

6. Thickening soil layer under tree crown, repairing drainage ditch inside and outside apple orchard, entering rainy season, timely drainage, preventing waterlogging under tree.