Nitrogen deficiency - Lettuce

Symptoms
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. Plants develop very long main roots and only a few secondary roots.

Reasons
Nitrogen deficiency on leaves and roots Nitrogen deficiency 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.

Symptoms
Plants with nitrogen deficiency develop very long main roots and less secondary roots than normal.

Reasons
Nitrogen deficiency on roots

Symptoms
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.

Reasons
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.

Symptoms
Symptoms of nitrogen deficiency start on older leaves with light green clorosis. Later the whole head is affected and looks yellow green. In varieties with anthocyanin, the leaves may have a purple flush. 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.

Reasons
Nitrogen deficiency (right) compared to optimum supply (left) Nitrogen deficiency 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.