Jujube hanging disease. The onset time is from May to June, and the main symptoms are longitudinal cracks in jujube hanging and a large number of fallen leaves. At the beginning of the disease, a light-colored to white slightly raised similar linear protrusion appeared longitudinally on the jujube hanging, and then cracked, and fungal pus appeared, showing a strip-like crack, weakening the tree momentum and seriously affecting the fruit setting and development of winter jujube.
In the later stage of the disease, the diseased part of the jujube hanging loses water, and some jujube hangings are broken and the flower buds fall off. When it is severe, there are fewer flower buds or even no flower buds, the fruit setting rate is significantly reduced, and even the fruit cannot sit down. In the later stage, the jujube hanging dried up, and the fruit sitting on the jujube hanging was greatly affected due to malnutrition.
Jujube hair disease. It often makes the jujube head bent, and the growth point loses the top advantage, and the strong jujube head cannot be formed, which has a great impact on the development of the tree. In the later stages of the disease, as the tree grows and develops, dry and cracked scars are formed.
Symptoms of leaf onset. The onset of jujube leaves generally begins in June, and the initial infection site of the fungus is the veins of the leaves. At the time of initial infection, the veins of the leaves appear light brown lesions, and gradually extend along the veins, turning brown or black, accompanied by the overflow of pus.
After the pus dries, it forms black pus-like spots, which resemble fungal pathogens. With the continuous infection and spread of scab, the necrosis of the leaf veins, and the leaf surface of the leaf veins began to appear water-stained, gradually drying up, forming "edge blight", and a large number of falling off, so people call it "edge blight".
This disease is a newly discovered disease in recent years, and some of the causes of overwintering and disease are unknown. According to the onset time and infection characteristics, it is believed that the infection point causing the disease is related to the stinging and sucking insect pests, such as the blind Tsubaki. It is observed that the rainfall from germination to young fruit stage (late May to mid-June) is too heavy, and the soil moisture content is too high, which is easy to cause the epidemic of this disease.
Control technology. The prevention and control of winter jujube scab disease needs to fertilize the soil, improve the soil, strive to improve the content of soil organic matter, increase the use of organic fertilizer and potassium fertilizer, and especially eliminate and reduce the application of fast-acting chemical fertilizer.
In the long run, create a good environment suitable for the growth and development of winter jujube trees; In particular, pre-flowering fertilizer should eliminate the application of a large number of pure fast-acting nitrogen and phosphorus fertilizers such as urea and diamine phosphate, fully coordinate the relationship between nutrition and reproductive growth, and strive to create conditions that are not conducive to the occurrence of diseases.
The management of early summer and winter dates is introduced here, and I hope it will be helpful to you. If you want to buy high-quality and high-yield winter dates, you can download the seed bank App, and the country's excellent winter date varieties are available for everyone to choose.
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