Pay Attention to Sulfur

Posted by Matt Hopkins|July 11, 2017

Sulfur (S) is an essential nutrient in crop production. Although it’s classified as a secondary element along with magnesium and calcium, it is sometimes called “the fourth major nutrient” because some crops can take up as much S as phosphorus, writes Mike Stewart, Director, North American Program, International Plant Nutrition Institute. Sulfur nutrition has gained
a lot of attention in recent years for several reasons. These include higher crop yields that require more S, less S impurities in modern fertilizers, and less use of S-containing pesticides. Furthermore, reduced industrial S emissions to the atmosphere has contributed to increased S shortages.

Sulfur serves many functions in plants. It is used in the formation of amino acids, proteins, and oils. It is necessary for chlorophyll formation, promotes nodulation in legumes, helps develop and activate certain enzymes and vitamins, and is a structural component of two of the 21 amino acids that form protein.

The crop’s need for S is closely associated with nitrogen (N). The relationship between S and N is not surprising since both are components of protein and are involved in chlorophyll formation. They are also linked by the role of S in the conversion of nitrate to amino acids. Crops having high N need will usually also have high S needs.