Symptoms of calcium deficiency and calcium supplementation techniques in Cucumber

Lack of calcium will lead to abnormal growth of cucumber, vegetable farmers should pay attention to identify the disease and supplement calcium fertilizer in time.

1. Symptoms of calcium deficiency in cucumbers

The mobility of calcium in plants is poor, so the symptoms of calcium deficiency are often manifested in new tissues, and the calcium content of young leaves is generally less than that of old leaves. When calcium deficiency, it is easy to cause heart leaf pathological changes, tip growth is blocked, leaves are yellow and curly, top leaves become smaller, dwarf symptoms appear, leaf vines turn brown and die. In case of continuous low light, and then suddenly sunny and high temperature, the leaf margin near the growing point curls, withered, parachute-shaped, the upper leaf veins yellowed, the leaf became smaller, and the root withered.

Second, the main causes of calcium deficiency in cucumbers.

1. The content of calcitonin in soil is insufficient. Calcium carbonate and calcium phosphate are the main sources of calcium in soil, but calcium deficiency often exists in sandy soil, old vegetable garden, continuous cropping vegetable garden and vegetable garden with low organic matter content.

two。 The content of available calcium in soil is low. Generally, there is no lack of calcium in soil, but ammonium ion, potassium ion, sodium ion and magnesium ion dissolved in soil solution can antagonize calcium ion and inhibit the absorption and utilization of calcium ion by vegetables.

3. The root system has poor ability to absorb calcium. The absorption of calcium by vegetables mainly depends on the root tip, and the absorption capacity is also poor if the root system is poor.

4. The mobility of calcium in the plant is poor. The main driving force of calcium transport in the plant is transpiration liquid flow. Calcium is transported to the vigorous growing organs through ducts and is basically no longer used for secondary distribution. Therefore, the organs with high transpiration intensity and longer growth time will get more calcitonin, resulting in calcium deficiency in upper leaves and fruits.

Third, the calcium supplement technology of cucumber.

1. Pay attention to the base fertilizer. On the basis of universal application of mature organic fertilizer, phosphorus and potassium fertilizer, sandy soil should apply calcium-magnesium phosphate fertilizer, calcium superphosphate, calcium nitrate and other calcium fertilizer; old vegetable garden and continuous cropping land should apply lime, the amount of calcium fertilizer per mu is 1.67-3.33 kg per year.

two。 Foliar fertilization. Add 1-2 kg of superphosphate to every 100 kg of water, stir for half an hour, and then soak for a period of time. The clear liquid above can also be sprayed with amino acid calcium, humic acid calcium, biological calcium fertilizer, etc., during the peak period of calcium absorption by vegetables.

3. Apply nitrogen and potash fertilizer scientifically. There is antagonism between ammonium ion and potassium ion and calcium ion. When the content of ammonium ion and potassium ion in soil is too high, and the ratio of nitrogen to calcium is too high, it can inhibit the absorption of calcium. The use of nitrogen and potassium should be properly controlled and scientific fertilization should be carried out to avoid the phenomenon of excessive nitrogen and potassium fertilizer.

4. Apply more organic fertilizer. Organic fertilizer is rich in organic matter and a variety of nutrients needed by crops. it is a kind of complete fertilizer and plays a unique role in improving soil and soil fertility.

5. Appropriate amount of boron fertilizer was applied. Appropriate amount of boron can promote the transport of carbohydrates from leaves to roots, promote the formation of new roots, which is beneficial to the absorption of calcium, and can be mixed with appropriate amount of borax when calcium is supplemented in soil and sprayed on leaves.

Liang Jiujie of Chengde County Agriculture and Animal Husbandry Bureau