What about the latest apple tree yellow leaf disease?

Apple tree yellow leaf disease is a common disease of apple trees, also known as yellow disease, iron deficiency chlorosis, etc., due to lack of iron caused by physiological diseases, from the young leaves of new shoots, the mesophyll first turns yellow, the veins remain green and reticulate, the whole leaves become yellow-white in the later period, the leaves are green and scorched, and finally the whole leaves die and fall early. Let's take a look at apple tree yellow leaf disease together. How to do it!

Causes of yellow leaf disease

Apple tree cultivation in saline-alkali soil or calcareous soil easy to occur yellow leaf disease, especially alkaline soil moisture too much serious disease, fruit growth exuberant, in case of continuous drought, soil salt content is too high, serious disease, yellow leaf disease after entering the rainy season to reduce or disappear. Orchards with high groundwater level, low-lying land and heavy clay quality are easy to suffer from chlorosis.

Spraying compound iron fertilizer solution

The compound iron fertilizer solution is prepared by adding 50 grams of citric acid into 50 kilograms of water, adding 150 grams of ferrous sulfate after the citric acid is dissolved, fully stirring, and adding 100 grams of urea after the ferrous sulfate is dissolved. Spraying method: spraying compound iron fertilizer solution before 10:00 a.m. or after 4:00 p.m. The fog should be fine and the spray should be uniform and thoughtful.

Injection of fruit tree green restoring agent

The injection fruit tree green restoring agent is suitable for large apple trees over 5 years old. First, a hole is drilled on the apple tree. The diameter of the hole is 7 mm and the depth is 5 - 6 cm. Generally, the hole is a hole at an angle of 120 degrees per week. Each tree is drilled with 3 holes. The sawdust is cleaned with an iron wire hook. The water outlet port of the sprayer is nailed into the drilled hole with a hammer. Then fill the pedal sprayer with diluted fruit tree green restoring agent 20 times liquid medicine (or 0.05 - 0.08% ferrous sulfate aqueous solution) prepared by distilled water or soft water, communicate with the water outlet interface, and then inject, each mature tree can inject 1 liter, and the trees in the early fruit stage can be appropriately reduced.

Application of organic fertilizer to fruit trees

Organic iron fertilizer made of ferrous sulfate and organic fertilizer in proportion was applied to soil during dormancy period of fruit trees, or mixed iron fertilizer solution was sprayed on leaves in early growth stage, or green restoring agent was injected into trunk of fruit trees. The effect of controlling yellow leaf disease of apple trees was better. Ferrous sulfate and high-quality decomposed organic fertilizer are mixed evenly according to the ratio of 1:15. When preparing, ferrous sulfate is dissolved in 10 times of water, and then the ferrous sulfate solution is sprayed on the organic fertilizer, and the mixture is mixed with milling while spraying to make it fully uniform. First dig a circular ditch along the periphery of the tree crown, 50 cm deep and 60 cm wide, then apply the mixed organic iron fertilizer evenly into the ditch, and water it immediately after covering the soil. Generally, 80~100 kg per tree for trees over 10 years old and 30~50 kg per tree for young trees under 10 years old. Organic iron fertilizer should be applied when applying base fertilizer in autumn, or before budding of fruit trees, but should not be applied during growing period to avoid phytotoxicity.