Sulfur (S)
Sulfur(S) is absorbed by the plant as SO4- and is not mobile in the plant. Sulfur may also be absorbed from the air and is a by-product of combustion. Deficiencies have increased in recent years primarily due to the use of higher concentrated fertilizers that do not contain S as an impurity and pollution controls that remove S at coal buring power plants.
Sulfur deficiency is characterized by chlorosis in the younger tissue near the top of the plant. A general yellowing of the whole plant may occur. General plant growth is stunted and branching is reduced. Fewer and smaller cotton bolls are generally produced. A S deficiency can also be induced in some cases by high rates of nitrogen(N) fertilizer. A N/S ratio of 15:1 in the cotton plant is generally considered optimum.
Soil conditions that may lead to sulfur deficiency include low organic matter and acid light textured soils where S has been leached. Reniform nematode damage on cotton roots have also produced S deficiency symptoms.
Images of sulfur deficiency symptoms
