Complete mineral nutrient

Growth normal; foliage healthy green color.

Nitrogen deficiency

Growth severely restricted, few stems; yellowing of older foliage.

Phosphorus deficiency

Growth thin, few stems; leaflets marginal scorch, older leaves shed.

Calcium deficiency

Growth fairly good; bushy appearance; young leaflets small, slightly chlorotic, forward roll and marginal scorch. This plant failed to form tubers of appreciable size. (see Plate No. 160)

Magnesium deficiency

Growth fairly normal; foliage slightly pale; older leaflets develop central necrosis, turn yellow or brown and wither prematurely.

Potassium deficiency

Growth tends to be squat and bushy; leaflets bluish green and slight intervenal chlorosis, marginal scorch and brown spots on under surface.

Nitrogen deficiency

Right: nitrogen deficient leaf, pale green and yellow tinted, contrasted with left, normal green leaf with ample nitrogen supply.

Phosphorus deficiency

Leaflets, lustreless green, marginal scorch and forward curling of margins. (cf. Plate No. 164, potassium deficiency)

Calcium deficiency

Acute deficiency condition. Shoots become thin; leaflets of terminal leaves small, margins chlorotic, incurled and may develop faint pink tints or necrotic brown spots or scorch; tips of leaflets die.

Calcium deficiency

Field plant. Bushy growth habit, thin shoots, small terminal leaves and scorched leaflets.

Calcium deficiency

Field view showing calcium deficiency induced by heavy potassic manuring on acid soil. Left foreground: no potash; plants bushy and squat, due to potash deficiency; Right foreground: heavy potassic manuring; plants tall, leaves rolled due to calcium deficiency.

Calcium deficiency

Top: calcium omitted, tubers dwarfed and useless; bottom: complete mineral nutrient, tubers normal.

Magnesium deficiency

Central intervenal necrosis pattern.

Magnesium deficiency

Field view. Leaves pale green, central intervenal chlorosis followed by necrosis and withering.

Potassium deficiency

"Bronzing" due to brown spotting, and scorching of leaves.

Potassium deficiency

Leaflets bluish green, slight intervenal chlorosis and backward curling of margins; intervenal spotting, marginal scorching. (cf. Plate No. 156, phosphorus deficiency)

Iron deficiency

Young leaver strongly chlorotic; veins may remain green; margins and tips brown patches.

Iron and Potassium deficiencies

Young leaves chlorotic due to iron deficiency; older leaves brown spotting and scorch due to potassium deficiency.

Manganese deficiency

Leaves from near tips of shoots still green, but showing characteristic brown spotting, mainly along veins.

Manganese deficiency

Field view. Stunted growth and dying of haulm at tips; leaflets of young leaves small, slightly chlorotic and strong forward curling of margins.

Manganese toxicity (soil acidity complex)

Severe toxicity. Necrotic lesions on leaves, mainly along veins and on petioles and stems.

Boron deficiency

Growth stunted; growing point killed; leaves dull grayish green, changing to yellow before dying off.

Boron toxicity and magnesium deficiency

Boron toxicity shown by narrow brown rims on leaflets; magnesium deficiency by intervenal necrosis and withering.

Chloride injury

Leaflets of terminal leaves slightly chlorotic, margins scorched and turned forward.

Potato Plant in Sand Culture

Growth Normal; foliage healthy green color.

Potato Plant in Sand Culture

Growth small and single thin shoots; upright habit; leaves pale green color.

Potato Plant in Sand Culture

Growth small and shoots thin; upright habit; leaves slightly pale, with forward roll and scorched margins; defoliation of oldest leaves.

Potato Plant in Sand Culture

Growth fairly good; young leaves chlorotic, forward roll and marginal scorch. This plant failed to form tubers of appreciable size.

Potato Plant in Sand Culture

Growth fairly good; foliage chlorotic and with intervenal necrosis; death of older foliage and severe defoliation.

Potato Plant in Sand Culture

Growth fairly good; leaves bluish-green and intervenal chlorosis, spotting and marginal scorch present.