Symptoms of nitrogen deficiency start on older leaves with light green clorosis. Later the whole head is affected and looks yellow green.
Strongly restricted growth and delayed crop development are further symptoms. Older leaves may decay. The shape of the leaves remains normal.
With severe N deficiency, no head is formed.
Nitrogen deficiency (right)
Symptoms may be confused with magnesium, sulfur or manganese deficiency.
With magnesium deficiency leaves become yellowish but in this case the veins remain green.
Sulphur deficiency also shows yellowish leaves, but symptoms start from the younger leaves here. Furthermore, leaves are less crinkled than normal.
Symptoms of manganese deficiency also show yellowish leaves, but growth is less restricted, the veins of the leaves remain green and brown necrotic spots appear on the edge of the leaves.