Sulfur is an essential element in forming proteins, enzymes, vitamins, and chlorophyll in plants, and in nodule development in legumes. Protein synthesis requires large amounts of sulfur, which plays an important role in the formation of oils within the seed, and is a constituent of several amino acids and vitamins found in both plants and animals. Thus, sulfur is an important factor in determining the nutritional quality of foods.
Sulfur is also important in photosynthesis and crop winter hardiness. Leguminous plants need S for efficient nitrogen fixation. An adequate S supply is very important, not only for crops with high sulfur requirements - legumes (alfalfa, clover, soybean etc.) and Cruciferae (canola, rapeseed) - but also for crops with high nitrogen requirement (corn, cotton), which must have adequate S to optimize their N utilization.
Deficiency symptoms: Leaves show a pale green color, which appears first on younger leaves. Eventually, the whole plant can assume a light yellow-green appearance.
Fertilizer sources: ICL Fertilizers' granular fertilizers ( SSP, GPK, GNPK, GNP) are not only excellent sources of N, P and/or K, but also supply substantial amounts of sulfur (of which they contain 6-13%). The sulfur is present as sulfate (SO4), a soluble form that can be taken up immediately by plants.