Grasp the best topdressing period of crops

corn

After the jointing to the trumpet period, the corn is the peak period of nutrient absorption. Generally, the first fertilizer can be applied before and after jointing. 150 kg of ammonium nitrate or 120 kg of urea can be applied per hectare; 7 to 10 days before the tasseling, The second fertilizer should be applied, and 225 kg of ammonium nitrate or 180 kg of urea can be recovered per hectare. If the base fertilizer and seed fertilizer are sufficient and the soil is very fertile, one can concentrate the top dressing and combine the second shovel for deep fertilization.

Sorghum

In order to meet the nutrient requirements of sorghum from jointing to heading, the first fertilizer should be applied at the jointing stage, and 150 to 225 kg of ammonium nitrate or 120 to 180 kg of urea should be applied per hectare; Fertilizer, 120 kg of ammonium nitrate per hectare or 75 kg of urea.

Rice

The absorption of nitrogen fertilizer by rice began to increase gradually after returning to green, and reached the peak of fertilizer absorption at the peak of tillering. In order to promote early tillering of rice, early application and heavy application of manure should be applied. Generally, 225 kg of ammonium sulfate can be applied per hectare 7 to 10 days after transplanting, and 100 kg of urea should be applied at the time of heading.

wheat

Wheat should be topdressed at the three-leaf stage, usually 195 to 270 kg of ammonium nitrate or 135 to 180 kg of urea per hectare. In the later stage of wheat, due to the weakening of nutrient uptake by roots from the soil, a top dressing should be carried out at the heading and flowering stage. 2,250 g of potassium dihydrogen phosphate per hectare, 22.5 ml of triacontanol solution and 300 kg of water are mixed. Spray; it is also possible to use 3000 g of potassium dihydrogen phosphate per hectare, add 15 kg of urea, and spray 450 kg of water.

Soy

Soybeans are crops that require more nitrogen fertilizer. Usually, nitrogen fertilizer is applied in the early flowering stage of soybeans, which can reduce the rate of flowering and falling, and can prolong the life of plants, increase grain weight and increase yield. Generally, 150 to 225 kg of ammonium nitrate or 120 to 180 kg of urea can be applied per hectare; in the period of soybean pod formation, a top dressing can be carried out, and the effect of increasing yield is more obvious.