"Release" refers to a process in which nutrients are converted from chemical substances into effective forms that plants can directly absorb and use (eg, dissolution, hydrolysis, degradation, etc.).
"Sustained release" is slow release.
"Controlled release" is controlled release.
First of all, we must clarify the three most important concepts here.
The classification of the International Fertilizer Industry Association, chemical synthesis of this type is called slow-release fertilizers; in addition, the *+ coating is a type called controlled-release fertilizer. There are other categories. As long as the standards for slow and controlled release fertilizers can be met, we can also say that it is slow and controlled release fertilizers.
Encapsulation is controlled physically. We call it chemical synthesis and it is micro-physical. There are also stable fertilizers with relatively large particles. This type of fertilizer is also defined in the International Chemical Industry Association. It is added in urea. Some digestive inhibitors make urea conversion slower. Such fertilizers are internationally known as stable fertilizers, but such fertilizers are not slow- and controlled-release fertilizers because they do not meet standards.
There are a lot of terms here, which are called in the industry standards of “slow and controlled release fertilizersâ€, slow and controlled release fertilizers, slow and controlled release of nutrients, initial nutrient release rate, cumulative nutrient release rate, average release rate, and nutrient release period.
What are the advantages of controlled-release fertilizer compared with ordinary fertilizer?
The first is to increase the utilization of chemical fertilizers and reduce the amount of chemical fertilizers. Since the slow-release fertilizer has a sustained-release effect, it can reduce the gaseous state and elution loss of the fertilizer, thereby increasing the utilization efficiency of the fertilizer. China's first company to convert slow-controlled release fertilizer production technology into productivity, the Shandong Kim Jungda Group has passed a large number of experimental data shows that: slow-release fertilizer can reduce fertilizer utilization from the original 35%, nitrogen loss rate was significantly reduced, Nitrogen fertilizer can save 30% -50%.
The second is to reduce the number of fertilization and save labor. Due to the lack of labor in the countryside or due to lack of water, water supply is not timely, and other reasons, the fertilization of crops has become increasingly simplified, and one-time fertilization of crops has become quite common. The one-off fertilizers currently sold on the market are basically quick-acting high-nitrogen compound fertilizers, and there is a risk of prolonged seedlings or later defertilization. The controlled-release fertilizer can be scheduled to design fertilizer release mode in the crop growing season, so that the nutrient release law of fertilizer and crop nutrient absorption consistent, one-time fertilization to meet the needs of the crop during the entire growing season.
When fertilizer is applied to the tomatoes, the fertilizer is applied once. When it is planted in the ground, it is not necessary to fertilize it, and it is finished when the seedlings are raised. In Japan, 70%-80% of slow- and controlled-release fertilizers are used on rice. When the nursery is growing, the fertilizer is used once on the seeds and roots, and no fertilizer is applied in the field.
Controlled-release fertilizers can also be used in no-tillage and soilless cultivation. Your seeds are good. When the standards are met, seeds and fertilizers can be planted in one go and irrigation can be done. This is very convenient.
Now many soilless cultivation irrigation nutrient solution. There are also a lot of problems, sometimes guilty of illness, and sometimes the nutritional solution is not well equipped, the seedling growth is not good, and the use of controlled-release fertilizers will solve this problem.
The third is to reduce crop diseases and improve the quality of agricultural products. Crop diseases and product quality are related to the amount of nitrogen fertilizer. Slow and controlled release fertilizers can prevent crops from excessively absorbing nitrogen and thus play a role in inhibiting diseases and improving quality.
