Metilurea is an important pharmaceutical intermediate. Its active chemical properties and good biocompatibility make it widely used in agriculture. In recent years, n methyl urea and its derivatives have been gradually developed into herbicides with high efficiency and low toxicity, which are used to improve the production efficiency and yield of rice, wheat, corn and other crops.
Application of Methylurea in Crop Weeding
Weeds are one of the main factors affecting crop growth and yield. Metilurea is an important herbicide component, and its derivatives can effectively inhibit the growth of weeds by affecting plant photosynthesis and metabolism.
Mechanism of herbicide action
methylurea derivatives (such as phenylmethylurea compounds) mainly achieve weeding effect in the following ways:
Inhibition of photosynthesis: Metilurea inhibits the photosynthesis of weeds by interfering with key enzymes in the photosynthetic electron transport chain (such as D1 protein in photosystem II), making them wither rapidly.
Destroy cell division: interfere with the microtubule assembly process in plant cells and prevent the normal growth of weed roots and stems and leaves.
Inhibition of metabolism: It interferes with protein and lipid synthesis in weeds, leading to their growth stagnation.
Application of Methylurea in Weeding Different Crops
Rice
Applicability: Metilurea herbicides have a good effect on common weeds in rice fields such as barnyard grass and Euphorbia.
Usage: Generally, it is sprayed after transplanting seedlings or when weeds appear in the field. The good water solubility of n methyl urea enables it to spread through water flow and cover weeds in the field.
Case: Nitroso methyl urea is a selective herbicide commonly used in paddy fields, which can effectively control weeds without damaging rice plants.
Pšenica
Applicability: There are many kinds of weeds in wheat fields, such as wild oats and descurainia sophia. Metilurea herbicides are safe for wheat by selectively inhibiting weeds.
Application effect: After spraying, methylurea can be quickly absorbed by weeds, interfere with their photosynthesis and metabolism, make them die gradually, and have little effect on wheat itself.
Kukuruz
Applicability: Metilurea herbicides show excellent control effect on weeds in corn fields, such as amaranth and Setaria viridis.
Case: For example, isopropylmethylurea compounds are widely used as post-emergence herbicides in corn fields to reduce the number of weeds in the field by inhibiting the germination of weed seeds.
Advantages and Limitations of N Methyl Urea
Advantages:
High efficiency, broad-spectrum effect on weed species.
Has low toxicity and is relatively friendly to the environment.
The residual time is short, which is suitable for field use of grain crops.
Limitations:
Long-term single use may lead to enhanced weed resistance.
Sensitive to environmental conditions (such as soil type, temperature and humidity), the effect may be limited.
Environmental Impact and Safety of Methylurea
Degradation and metabolism
Metilurea and its derivatives degrade rapidly in soil and water, and the final products are carbon dioxide and inorganic salts, which has low cumulative pollution to the environment.
Effects on non-target organisms
The low toxicity and good selectivity of n methyl urea make it have little influence on non-target plants and organisms. However, scientific application is still needed to avoid the ecological imbalance of soil microorganisms caused by excessive use.