Causes and Prevention methods of calcium deficiency in Tomato with uneven coloring caused by calcium deficiency

Growing tomato is prone to navel rot, fruit cracking, poor coloring and other diseases, which affect the quality and appearance, all of which are caused by calcium deficiency. Therefore, the cultivation of tomato should pay attention to calcium supplement in order to ensure the normal and smooth growth of tomato, prolong the flowering and fruiting period, high yield and good quality.

Calcium deficiency in tomato

I. symptoms of the disease:

The symptoms of calcium deficiency in tomato are short plant, thin plant, sagging leaves and so on. In the early stage of calcium deficiency, the edge of the heart leaf yellowed and wrinkled, and when it was serious, the heart leaf withered and died. Large black-brown patches were formed in the middle leaves of tomato plants, and then the leaves of the whole plant turned over, lost green and showed yellowish color. Tomato navel appears watery light yellowish brown to dark green brown disease spot, the surface is uneven, disease tissue necrosis, also known as navel rot. In the tomato expansion and maturity period, such as insufficient calcium supply, there will be fruit cracking, poor coloring, the formation of green back fruit, gluten rotten fruit, brown fruit, so that the tomato loses its luster.

Second, the cause of the disease:

The causes of calcium deficiency in tomato are as follows: first, excessive application of nitrogen and potassium fertilizer hinders the absorption and utilization of calcium by roots; second, the soil is too dry and the concentration of soil solution is high, which affects the absorption and utilization of calcium by roots; third, the air humidity is too small and the water evaporates much and quickly, which affects the absorption and utilization of calcium by roots; fourth, if the soil is acidic, the calcium content is low, which can not meet the needs and utilization of calcium in tomato. Fifth, the calcium in the soil is fixed and can not be absorbed and utilized by the roots.

3. Prevention and control measures:

The main results are as follows: 1. Base fertilizer ensures calcium content. When planting tomato, using calcium superphosphate or calcium magnesium phosphate fertilizer as base fertilizer can obviously increase the content of calcium in soil, and it is appropriate to use 80-100 kg per mu. At the same time, retting mature human and animal manure and biological fertilizer as base fertilizer can increase the content of active calcium in soil, benefit the absorption and utilization of tomato roots, and avoid calcium deficiency in the process of tomato growth. Acid soil, when preparing the soil, apply 50-60 kg cooked lime powder per mu to neutralize the acidity of the soil and increase the soil calcium.

2. foliar spraying water-soluble calcium. In the process of tomato growth, water-soluble calcium is sprayed on the leaf every 7-10 days for 2-3 times. The effect of calcium supplement is good, and various physiological diseases caused by calcium deficiency can be corrected in time, especially the expansion and maturity period of tomato is the key time to supplement calcium. Can spray 0.3% Mel 0.5% calcium nitrate aqueous solution, 0.1% Mel 0.2% calcium chloride aqueous solution, 400-500 times active calcium aqueous solution, etc., can effectively supplement calcium.

3. Ensure water supply. In the tomato growing period, especially in the flowering and fruiting period, it is necessary to ensure an adequate water supply. In case of high temperature and drought, attention should be paid to irrigation to keep the soil moist, so as to promote the absorption of calcium by roots, improve the utilization rate of calcium by roots, and effectively prevent physiological calcium deficiency.