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Manganese Deficiency Symptoms

Low availability of manganese (Mn) is usually associated with alkaline soils (above 7.5 pH) and excess of Mn with acid soils (below 4.5 pH). In India since groundnut is mostly grown in the soils having pH more than 7.5 there is high incidence of Mn deficiency. The main symptom of manganese deficiency is chlorosis or yellowing between the veins of new leaves. There may also be a distinguishing characteristic of brown spots on the leaf margin (observe in the picture).