Phosphorus deficiency

Leaf sheaths, strong purple tints.

Magnesium deficiency

Leaves pale green; bead-like grouping of green coloring matter and later yellowing and intervenal necrosis.

Potassium deficiency

Leaves and stems bluish green; older leaves die back from tips and wither.

Potassium deficiency

Showing tip die-back and bright reddish brown "firing" effect.

Iron deficiency

Young leaves severe chlorosis; chlorosis begins as intervenal stripes.

Iron deficiency

Heads and subtending leaves chlorotic.

Manganese deficiency

Leaves, grayish-brown elongated specks and streaks, most prevalent in basal halves; breaking of leaves with distal areas remaining green; empty panicles.

Manganese deficiency

Irregular, grayish-brown lesions, which coalesce and bring about collapse of leaf (gray speck symptoms).

Manganese deficiency

Field comparison of susceptibility. Oats (center) more susceptible than barley (left) and wheat (right).

Iron and Manganese deficiency

Two left, iron deficiency chlorotic stripings; two right, manganese deficiency lesions; three center, manganese and iron deficiency symptoms (lesions and striping).