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Iron (Fe) deficiency is common in calcareous soils (>7.5 pH) and in poorly drained soils. Legumes like groundnut are particularly sensitive to iron deficiency. The main symptom of iron deficiency is chlorosis or yellowing between the veins of new leaves. The chlorosis or yellowing between the veins also results due to zinc deficiency. Iron chlorosis extends to full length of leaves where as Chlorosis due to zinc deficiency occur mainly on the lower half of the leaves.

   

Groundnut crop affected by iron deficiency (left) and iron deficiency corrected crop (right) by spraying of ferrous sulfate.