I. Maize: After the jointing stage until the Dagukou period, it is the peak period for absorbing nutrients. Generally, the first fertilizer can be applied before and after jointing, and 150 kg of ammonium nitrate or 120 kg of urea can be topdressed before each hectare. In the 7-10 days, the second fertilizer should be applied, and 225 kg ammonium nitrate or 180 kg urea can be applied to each hectare. If the base fertilizer and seed fertilizer are more abundant and the soil is very fertile, you can concentrate on topdressing once again, and combine the second spade for deep fertilization. Second, Sorghum: In order to meet the requirements of sorghum from jointing to heading nutrients, the first fertilizer should be applied at the jointing stage, 150-225 kilograms of ammonium carbonate or 120-180 kilograms of ammonium carbonate should be applied per hectare; For the second fertilizer, 120 kg of ammonium carbonate or 75 kg of urea is applied per hectare. III. Soybeans: Soybeans are crops that require more N fertilizers. They are usually applied once at the early flowering stage of soybeans. This can reduce the rate of falling flowers and plants, and can prolong the life span of plants, increase grain weight, and increase yield. Generally, they can be recovered per hectare. Ammonium bicarbonate 150-225 kg or urea 120-180 kg; during the period of soybean crusting, extra-root dressing can be carried out once more, and the effect of increasing production is more obvious. Fourth, sunflower: In addition to planting sunflowers to apply enough fat. Usually topdressing during the budding period, hectares topped 225 kg of ammonium carbonate or 180 kg of urea. Conditional farmers can also perform extra-root dressing in the flowering period. Fifth, castor: timely ricin top dressing, can promote early maturation and high yield. The first top dressing can be combined with Dingmiao, 225 kg of ammonium carbonate or 180 kg of urea per hectare of the whole nation. The second topdressing is carried out before flowering of ramie. The main fertilizer is phosphorus, which can increase the yield. Related soil fertilizer testing equipment please see: http://?id=50 Two Cups Coffee Maker,2 Cup Coffee Maker,Two Cup Coffee Machine,Dual Coffee Maker Aiosa , https://www.nbaiosa.com