First, the characteristics of urea Urea is an amide nitrogen fertilizer and is currently the main nitrogen fertilizer. Among the nitrogen fertilizers used, urea accounted for more than half. Its main features are: (1) The highest nitrogen content in solid nitrogen fertilizer. The general nitrogen (N) is 46%. (2) Water-soluble, quick-acting nitrogen fertilizer. Before the urea is applied to the soil, its chemical properties are stable. Unlike ammonium bicarbonate, it is easily decomposed in the air and is a favorite nitrogen fertilizer for farmers. Urea is topdressing with less dosage and quicker results. (3) Urea is a neutral, molecular organic nitride, and molecular urea can be directly absorbed by crop roots, but the amount is small. After the urea is applied to the soil, it can only be absorbed by the crop roots in large quantities only after it is hydrolyzed into ammonium nitrogen under the action of urease in the soil. Second, the application of technology Urea can be used as basal fertilizer and topdressing fertilizer, and generally it is not directly used as seed fertilizer. Because of poor mastery, high concentrations of urea can affect seed germination and radicle growth. If you must do seed fertilizer application, separate from the seed, and the amount of urea should not be too much. 1, base fertilizer When urea is used as a basal fertilizer, the application amount must be carefully calculated. Because urea has a high nitrogen content and is a high-concentration nitrogen fertilizer, the application amount must be appropriate, otherwise it will cause malnutrition and reduce the nitrogen utilization rate. The use of urea as a base fertilizer must be applied to a certain depth of the soil layer, especially on slightly alkaline calcareous soil. If urea is applied on the surface, the volatilization loss of ammonia is even more serious than that of ammonium bicarbonate, up to 30%~60. %. Food crops are applied at the tillering stage or jointing stage, and can be applied by ditching or hole application. After fertilization, the cover soil is tightly closed to prevent the volatilization of ammonia after hydrolysis. When urea is applied as topdressing in the soil, the fertilization period should be applied several days earlier than other available nitrogen fertilizers such as ammonium sulfate, ammonium bicarbonate, etc., because urea can only be absorbed by crops only after it is converted into ammonium nitrogen. How many days in advance, depends on the season and temperature, early spring gas (low temperature 10 °C) to advance 6 to 7 days, late spring and early summer (16 ~ 20 °C) 3 to 4 days in advance, summer 1 to 2 days in advance. Leakage and leakage are more serious on sandy land, and the amount of fertilizer should not be too much. Scientific application of urea should pay attention to the following matters: (1) When urea is used as a top dressing, it can be applied to the apical part of the crop and is also suitable for foliar spraying. (2) Urea is suitable for foliar application of various crops. The appropriate concentration is generally between 0.2% and 2.0%, and varies depending on the crop type and growth period. When spraying urea, it is important to note that the content of biuret, the accessory component, is less than 0.5%. (3) Urea is not suitable for seed fertilizers, mainly because of high nitrogen content. Simultaneous use with seeds can easily result in seedling emergence and burning. Some urea is of poor quality and contains a certain amount of biuret to poison germination and seedlings. The health benefits of capsicum include relief from cancer, peptic ulcer, menopausal problems, low risk of cardiovascular disease and diabetes. it has anti-inflammatory, analgesic properties and may also provide relief in pain related to arthritis. it also provides relief from fibromyalgia, skin aging and psoriasis. our quality is the best and we are offering them at promotional prices to expand on our market in your zone. Red Chile,Red Hot Peppers,Red Chili Pepper,Red Chilli Pepper Jining Yuanheng International Trading Co.,Ltd , https://www.china-garlic-exporter.com
(4) Urea needs to be transformed before it can be absorbed by crops. The products of urea conversion in soil are ammonium carbonate and ammonium bicarbonate. Therefore, the agricultural chemical properties of urea when applied to soil are similar to those of ammonium bicarbonate. It also causes ammonia volatilization loss, so it is necessary to apply deep soil. It is a misconception that the kind of urea is not "fat and fat".
2, top dressing
Urea characteristics and application techniques