黄色成人免费毛片_午夜福利高清视频_一级夜理论片久久_欧美 日韩 国产高清在线_人妻被内射中文字幕_欧美美剧电影大全免费观看全集免费_国产哟交泬泬视频在线播放_國產精品白漿無碼流出_亚洲国产情成人精品青青草原_春药精油按摩高潮不止

First, different crops react differently to nitrogen

For corn, wheat and other cereal crops, ammonium nitrogen (such as ammonium bicarbonate, ammonium sulfate, ammonium chloride, urea) or nitrate nitrogen fertilizer (such as ammonium nitrate) is applied. Potato and sweet potato should use ammonium nitrogen fertilizer. In addition, the nitrogen requirements of different crops are different. Leafy vegetables require more nitrogen fertilizer for the leaves to be harvested, while legumes need only apply a small amount of nitrogen fertilizer at the early stage of growth and when the nodule has not yet functioned.

Second, different crops react differently to phosphorus

Legume crops (soybeans, peanuts), fiber crops, potato crops (potato, sweet potato) and melons require more phosphorus, and the application of phosphate fertilizer has a better effect. Both calcium and heavy calcium are water-soluble phosphate fertilizers, which are easily absorbed and utilized by crops.

Third, different crops react differently to potassium

Crops containing more carbohydrates (potato, sweet potato, watermelon, etc.) require a large amount of potassium, which is a potassium-producing crop. These potassium-producing crops are all nitrogen-free. If potassium chloride is applied, the yield and quality will decrease. Potassium sulphate is suitable for various soil crops, and can be used as base fertilizer, seed fertilizer, top dressing and top dressing. Potassium chloride is not suitable for seed fertilizer.

Spring ploughing fertilizer should select suitable fertilizer varieties according to the characteristics of crops, which can fully exert the fertilizer efficiency, reduce the production cost and obtain high yield.