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Phosphorus Nutrition

• Phosphorus application is not only important for groundnut crop growth but also equally important for biological nitrogen fixation.

• Phosphorus is essential for root and shoot growth and lengthening.

• It stimulates the setting of pods, decreases the number of unfilled pods (pops) and hastens the maturity of the crop.

• Phosphorus is essential to form compounds in the plant body that provide energy for the growth and development of groundnut plants.

• Phosphorus is to a plant what wheels are for a car.

• As a car cannot run on flat tyre even if the petrol tank is full, without phosphorus plant cannot grow even nitrogen supply is in plenty.

• Phosphorus availability helps in increased efficiency of nitrogen use by plants.

• About 25-50 kg of phosphorus (P2O5)/ha has been recommended for different groundnut-growing regions in India.

• However, it is a good practice and also economical to apply phosphorus based on soil- test recommendations.

• Entire phosphorus (P2O5) should be applied at the time of sowing as a basal-dressing as the demand for phosphorus is high during the early stages of crop growth.

• Furrow placement or side dressing is the best method of phosphorus application in the soil. This method of application minimizes the fixation of phosphorus in the soil.

• Phosphorus fixation means unavailability of phosphorus for plants’ use.

 

     

• Groundnuts are extremely sensitive to fertilizer burn. Do not apply fertilizer in the furrow with the seed nor over the row after planting.

• It has been found that single super phosphate is the best source of phosphorus as it also contains calcium (19.5%), sulphur (12.5%) in addition to phosphorus (16%). Super phosphate also contains zinc and magnesium in traces.