Symptoms
When nitrogen is deficient, potato leaves are a pale yellowgreen, small in size and drop prematurely. The plant is stunted in growth with only a few thin stems. Yields are low as few tubers are formed.
Reasons
Nitrogen deficiency (right).
N is largely needed during leaf formation and then for tuber growth and yield. The right rate and timing of N is important in managing potato yields, tuber size and desired quality characteristics.
Sulfur deficiency, root parasites (e.g. PCN), deep drilling of tubers, nightfrosts, water shortage or heavy metal toxicity can cause similar symptoms.