What Causes Abnormal Growth of the Cucumber Growing Tip? Causes and Control Measures
The apical growing point of the cucumber is called the "growing tip" (longtou). Whether a cucumber plant grows vigorously depends on the growth of this growing tip. Under normal conditions, the small leaves at the top of the growing tip are green, yellow-green, and tender yellow, with even color and no pests or diseases. However, during cultivation, the growing tip often shows symptoms such as rotten tips and yellow tips. What causes this? Let's find out together.
1. Phytotoxicity
Cucumbers suffer greatly from diseases during growth. To control diseases, many farmers tend to increase the concentration of pesticides or mix pesticides arbitrarily, which easily causes phytotoxicity. After phytotoxicity occurs, it shows as dry or yellowing leaf margins, deformed leaves and fruits, and spots or lesions. Therefore, when controlling pests and diseases, the concentration and dosage must be strictly controlled. Do not overuse pesticides, and try to avoid mixing pesticides, especially mixing with copper-based formulations, to prevent phytotoxicity and abnormal growing tips.
2. Diseases
Diseases are also one of the causes of rotten and yellow cucumber tips, such as scab and gray mold. Brown spot disease, when severe, can also cause a large number of yellow spots on the top leaves of cucumbers, forming yellow tips. In low-temperature winter seasons, vine wilt disease is prone to occur and also causes rotten cucumber tips. Other cucumber diseases such as bacterial marginal blight, scab, gray mold, and gray blight can all cause rotten cucumber tips. Therefore, when diseases cause abnormal growth of the cucumber growing tip, first identify which disease is causing it, then apply the appropriate treatment.
3. Nutrient Deficiency
Nutrient deficiency is also one of the causes of abnormal growth of the cucumber growing tip. When the plant lacks zinc and iron, yellow tips easily occur: first the top leaves turn yellow, with yellowing and whitening between the veins, then the yellow leaves spread from top to bottom, and gradually the leaf margins become necrotic and dry. When calcium is deficient, rotten tips easily occur: first the top leaves begin to rot from the leaf margins or between the leaves, and finally the cucumber growing point disappears. Therefore, fertilization must be balanced. Not only should the balance between organic fertilizer and chemical fertilizer be considered, but also the balance between trace elements and secondary elements. Calcium fertilizer should also be supplemented in time to avoid rotten tips caused by nutrient deficiency.
4. Hormone Toxicity
When dipping cucumber flowers, excessive pesticide concentration or pesticide liquid splashing onto cucumber leaves and stems can cause hormone toxicity in cucumbers, which can also lead to abnormal growth of the growing tip. After hormone toxicity occurs, the leaves begin to yellow, the top leaves become hard and brittle, and growth slows or even stops. Therefore, when dipping cucumber flowers, the pesticide concentration must be well controlled, and operations must be done carefully.
The above is an introduction to the causes of abnormal growth of the cucumber growing tip and control measures. We hope it helps you. For more related knowledge, please follow us.