Urea containing more than 45% nitrogen, is a high concentration of amide nitrogen fertilizer, applicable to all kinds of soil and crops, and is widely used by farmers. However, the application should be scientific, otherwise it will reduce the effect of fertilizer. Specifically speaking, it should be done "three should be three avoid." Three should be: One should be deep. Whether urea is used as a base fertilizer or as a top dressing, deep application should be made. Deep application can not only control the hydrolysis rate of urea, enable it to release nitrogen nutrition evenly, but also prevent the loss of nitrogen volatilization and improve the utilization rate. The depth of application is generally about 10cm. The second should be applied early. Urea has a conversion process in the soil, which needs to be hydrolyzed into ammonium ions and further oxidized into nitrate ions before it can be absorbed by crops. If the application time of urea is the same as other nitrogen fertilizers, it will inevitably delay the maximum effect period of crops on nitrogen nutrition. Therefore, when using urea as top dressing, it is generally 3-5 days ahead of schedule. Three should spray. Urea is a neutral fertilizer, and it is an organic compound. It contains no auxiliary components and has a small burn on the stems and leaves of crops. Urea molecules are small, easy to penetrate the cell membrane, is conducive to leaf absorption, urea nitrogen content is high, can quickly participate in the synthesis of amino acids in the leaves, into a protein, its number and speed are more than other nitrogen fertilizer. Therefore, urea is very suitable for spraying foliar fertilizers. The third bogey is: a taboo table. In particular, saline land is even less suitable for surface application. Because ammonium carbonate, ammonium bicarbonate, and ammonium hydroxide produced after the hydrolysis of urea are unstable compounds, they are easily volatilized and cause losses. Second bogey dip, seed dressing. Urea contains a small amount of biuret, which is toxic to crops. Dressing with urea will destroy the protein structure of the seed and denature the protein, affecting the seed germination and root growth of the seedlings. In severe cases, the seed will lose its germination power. Three bogey water immediately after application. After the urea is applied to the soil, it is dissolved in the molecular state in the soil before it is converted into ammonium bicarbonate, and it is not easily adsorbed by the soil. If irrigation is performed immediately, the fertilizer will be lost along with the water. Therefore, after the application, the irrigation should be performed every other day and light irrigation should be performed. Slowly poured. China Agricultural Network Editor
Garlic Bulbs,Fresh Garlic,Garlic
Toboli International Trading Co., Ltd. , http://www.jnapplefruit.com