First, it should not be mixed with alkaline fertilizers or applied at the same time. Urea must be converted into ammonia nitrogen after application will produce fertilizer effect, while ammonia nitrogen in alkaline conditions, most of the nitrogen will become volatile ammonia, so urea can not be alkaline with lime, plant ash, calcium magnesium phosphate, etc. Fertilizers are mixed or applied simultaneously. In general, in summer and autumn, urea and alkaline fertilizers should be staggered for 3 to 4 days, and winter and spring should be staggered for 7 to 8 days.
Second, it is not suitable for seed dressing. In the production process of urea, a small amount of biuret is often produced. When the content of biuret exceeds 2%, the seeds and seedlings will be poisoned. Such urea enters seeds and seedlings and denatures the protein, affecting seed germination and Seedling growth, it is not suitable for seed fertilizer. If it must be used as a seed fertilizer, avoid seed and fertilizer contact and control the amount.
Third, it is inappropriate to apply water immediately after application. Urea is an amide nitrogen fertilizer, it must be converted into ammonia nitrogen can be absorbed and used by the crop roots, the conversion process due to soil quality, moisture and temperature and other conditions, the length of time, usually in 2 to 10 days to complete, if Immediately after the irrigation or dry land is applied before heavy rain, urea will be dissolved in the water and lost. Generally summer and autumn should be 2 to 3 days after application to irrigation, winter and spring season should be watered after 7 to 8 days after application.
Fourth, the surface should not be applied. Urea is applied to the surface of the earth and it can be used after 4 to 5 days of conversion at room temperature. Most of the nitrogen is easily volatilized during the ammoniation process. Generally, the actual utilization rate is only about 30% if it is in alkaline soil and organic matter content. Spreading in high soil, nitrogen loss will be faster and more. And shallow urea, easily consumed by weeds. Deep application of urea, melting of fertilizer in soil, fertilizer in a moist soil, is conducive to the exertion of fertilizer efficiency. For topdressing should be applied next to the seedlings or ditch applied on the seedling side, the depth should be about 10 ~ 15cm. In this way, urea is concentrated in the root-dense layer, which facilitates the absorption and utilization of crops. Tests have shown that deep application of shallower application can increase the utilization of urea by 10% to 30%.
Fifth, it should not be used too much. The nitrogen content of urea is high and the application amount should not be too large, so as to avoid unnecessary waste and “fat harmâ€. Generally, 5 to 15 kg per mu, and 15 to 20 kg per mu for paddy fields. Excessive application can not be absorbed by the soil before it is converted to ammonium bicarbonate. It is easily leached by rainwater and can easily harm crops. At the same time, too much urea is applied, most of which are lost and enter the groundwater, which will lead to nitrogen pollution in the water, resulting in the deposition of nitrite and seriously affecting the safety of people and livestock.
Sixth, it is not suitable for high concentration foliar spray. Among all nitrogen fertilizers, urea is the best foliar fertilizer. When urea is sprayed, the amount and rate of protein synthesis in the crop exceed those of other nitrogen fertilizers. However, when foliar spraying, avoid excessive concentration of urea solution, otherwise it will burn the leaves and poison the plants. Usually 2% is suitable for the concentration of corn, rice, etc.; 0.5%~1.5% of vegetables and melons are suitable.
VII. It should not be used too late. Urea application is too late, is not conducive to the exertion of fertilizer efficiency, easy to cause crop greed green late, it should generally be applied 4 to 7 days earlier than other nitrogen fertilizer application.
Eight, should not be applied to celery. During the entire growth of celery, a large amount of nitrogen fertilizer should be applied, but no urea should be applied. Because topdressing urea will make the celery fiber thicker and thicker, the plants will age, grow slowly, and will have a bitter taste when eaten, resulting in poor quality.
Vc Whitening Moisturizing Cleanser
Efficacy: complete removal of the skin of dirt, with whitening, Blemish effect, but also increase the skin's luster, make skin feel instantly cool.
Function Type: cleanser, cleanser
Skin: all skin types, has a good antibacterial effect, can effectively clean skin whitening. Cool-cool, so you vitality doubled.
Companies registered capital of 35 million yuan, the end of 2014 the total assets of 48.69 million yuan, including fixed assets of 37.52 million yuan. The company's existing cooperation Orange cultivation base 7043.5 acres, the company production base is located in Jiangxi County Tech Industrial Park Chu Tan industrial area, covers an area of 120 acres, it has built a standard plant 9,000 square meters, Nissan 6000 kg Orange enzymes and other liquid enzyme products. Enzyme, known as enzyme, refers to a polymer substance having biocatalytic functionality. In the catalytic reaction system an enzyme, the reactant molecules are known as substrates, enzyme substrates by catalytic conversion to another molecule. Almost all cellular activity of enzymes involved in the process are required to improve efficiency. Similar to other non-biological catalysts, enzymes chemical reactions by lowering the activation energy to accelerate the rate of the reaction, most of the enzyme catalyzed reaction rate can be increased a million times; in fact, the enzyme is to provide an activation energy needs than another low way, so that more particles to have less than the activation energy of the reaction kinetic energy, thus speeding up the reaction rate. Enzyme as a catalyst, in itself is not consumed during the reaction, it does not affect the chemical equilibrium reactions. Positive enzyme catalysis, but also a negative catalytic effect, not only to accelerate the reaction rate, but also to reduce the reaction rate. And other non-living catalysts is different, having a high degree of specificity of enzyme, only a catalytic reaction or produce a particular specific configuration.
Vc Whitening Moisturizing Cleanser,Remove Skin Dirt Cleanser,Fast Whitening Skin Cleanser,Effective Antimicrobial Blemish Cleanser
Ganzhou Green days Biochemical Technology Co., Ltd. , http://www.cn-gangdao.com