Phosphorus deficiency

Older leaves dull purple tints.

Calcium deficiency

Older leaves, marginal and intervenal collapse; young leaves, cupping and distortion and scorching of margins.

Magnesium deficiency

Older leaves chlorotic marbling.

Potassium deficiency

Older leaves severe marginal scorch and forward curling of leaf margins.

Insect injury

Growing point injured; may be confused with boron deficiency (cf. Plate No. 091).

Iron deficiency

Severe chlorosis of leaves beginning as a chlorotic mottling.

Manganese deficiency

Leaves severe intervenal chlorotic marbling and necrosis.

Manganese toxicity (soil acidity complex)

Leaves cupped; margins white mottled bands, later brown necrotic spots and scorching, and appear ragged.

Boron deficiency

Longitudinal section showing necrosis and splitting of pith.

Molybdenum deficiency

Leaves cupped and show chlorotic mottling, especially around margins; tips and margins develop dead patches; plants fail to heart. (Similar to manganese toxicity) (cf. Plate No. 060)