The relationship between soil EC value and crop growth
1. EC value concept
The EC value is used to measure the soluble salt concentration in the solution, and can also be used to measure the soluble ion concentration in liquid fertilizers or planting media.
2. Reference standard for EC value
The EC value of general irrigation water is required to be less than 0.8, and the ideal EC value for plant growth is usually 0.2-0.6
The maximum should not exceed 2.5.
3. Soil EC value suitable for crop growth
The EC value can briefly indicate the conductivity of the salt solution level. Salt from irrigation water, soil, and rising groundwater are responsible for the high conductivity. Its main components include sodium ion, magnesium ion, calcium ion, chloride ion, sulfate ion and carbonate ion.
The EC value can only indicate the total concentration of soluble salts, and cannot reflect which specific ion it is. The higher the soil EC value, the greater the concentration of soluble salt ions in the soil, which will damage plants and reduce plant yield and quality. This is because high-conductivity solutions will cause permanent damage to the top and edges of the leaves. It can even cause leaf wilting and plant death. At the same time, it is possible to form reverse osmotic pressure to replace the water in the roots of the plant, which will damage the root tips and lose the ability to absorb water and nutrients. This is also the reason why excessive fertilization can cause burning seedlings. Above-ground plants show symptoms such as wilting, chlorosis, tissue necrosis, or short plants. The symptoms of the roots are: in mild cases, the root tip turns brown, the lateral roots are dry, and there is no root hair; in severe cases, the entire root system rots and die. Too high soil EC value will also increase the incidence of root rot (caused by Spongi rot bacteria).
The soil EC value is too low, indicating that the lower the concentration of soluble salt ions in the soil, the less nutrient content that can be absorbed by plants, such as the content of nitrogen, phosphorus, and potassium ions in the soil. Nitrogen, phosphorus, and potassium are the three basic elements necessary for plant growth, and long-term lack of it will cause poor plant growth.
When crop plants are found to grow slowly or stop growing, avoid blindly topdressing to supplement nutrients.
First of all, we should observe the condition of the plant roots and make judgments based on the characteristics of the substrate and the management of water and fertilizer. If necessary, an EC meter can be used to detect the EC value of the soil. When the absorptive capacity of plant roots decreases, unreasonable fertilization will cause soil salt to accumulate again and accelerate plant death;
Secondly, use water with a lower EC value to irrigate and rinse the soil to reduce the soil salt concentration;
Third, rooting agents can be used appropriately to promote the growth of plant roots and accelerate the restoration of plants to normal.
When the EC value is too low, properly increase fertilizers and supplement soil nutrients to ensure normal plant growth.
