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Potassium Deficiency Symptoms in Groundnut

Potassium deficiency should be confirmed before applying potassium to the crop. This is because excessive potassium can be detrimental to a groundnut crop. High levels within the fruiting zone (top two to three inches of soil) are associated withpod rot.
Potassium also reduces calcium uptake at pegging, resulting in a high percentage of "pops." Lack of potassium causes stunted plants with small branches and little vigor.

  

Potassium-deficient plants exhibit chlorosis (loss of green color) or yellowing along the leaf margins or tips starting with the bottom leaves and progressing up the plant. In severe cases, the leaves appear dry and scorched at the edges and the surfaces are irregularly chlorotic. The difference between yellowing of leaves due to N and K deficiencies is that the yellowing of leaf starts from midrib and spreads towards the edges of leaf in N Deficiency, whereas in case of K deficiency yellowing starts from edges of leaf and spreads inwards (observe in the picture).