1　硫在农业生产中的重要作用硫与氮、磷、钾三要素一样是作物的主要营养元素 ,作物对硫的需求量与对磷的需求量相似 ,被称为第四大营养元素。硫对作物的正常生长具有十分重要的作用 :硫对作物蛋白质、油脂、维生素以及某些酶的合成起着重要的作用 ;硫能促进根瘤菌和自生固氮菌 1 Sulfur plays an important role in agricultural production. Sulfur is the main nutrient element of crops, which is the same as nitrogen, phosphorus and potassium. The demand of sulfur for crops is similar to the demand for phosphorus, and it is called the fourth largest nutrient element. Sulfur plays a very important role in the normal growth of crops: Sulfur plays an important role in the synthesis of crop proteins, fats, vitamins and some enzymes; Sulfur promotes the growth of rhizobia and azotobacter