What is the cause of yellowing of cucumber leaf margin? How to prevent it?
Cucumber is a crop that can be used as both a vegetable and a fruit. It is very popular in winter and summer. However, in cucumber planting, some diseases often occur, some are physiological and some are infectious diseases. There is such a phenomenon, sometimes you will see the yellowing of the cucumber leaf edge, like a circle of gold rims, then why? What solutions?
Analysis of the causes of yellowing of cucumber leaf margin:
In fact, cucumber leaves have this symptom. Vegetable farmers with many years of experience may be able to see that the real reason for this is the physiological barrier of cucumber caused by excessive application of nitrogen fertilizer.
How to solve the problem of yellowing of cucumber leaf edge?
1. The best solution is to control the amount of nitrogen fertilizer used. Although nitrogen fertilizer is a large amount of elements required for crops, it can promote the formation of chlorophyll, and the growth and development of plants also have a great influence. However, insufficient or excessive nitrogen nutrition in crops can cause abnormal growth of crops.
2. For the physiological diseases caused by excessive nitrogen, foliar spray of superphosphate fertilizer can help the plant to strengthen and relieve physiological diseases.
3. If the cucumber has not yet developed this physiological disease, it is necessary to strictly control the application amount of nitrogen fertilizer, and the application period of nitrogen fertilizer should be strictly controlled.
4. Less use of ammonium nitrogen and more nitrate nitrogen. After the nitrate nitrogen is applied, it is not easily adsorbed by the soil, so the concentration of the soil solution does not increase much. Therefore, the application of nitrate nitrogen in cucumber is an important measure to prevent physiological diseases and ensure good growth.
5. Use less fertilizer and more biological and organic fertilizers.
In addition to the above points, it should be noted that the cucumber in the greenhouse may be larger than the cucumber in the open field. Usually, there is no natural rainwater irrigation. There may be residual fertilizer left in the soil, so vegetables are grown in the greenhouse. It is possible to reduce some chemical fertilizers and apply some organic fertilizers.
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