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Estimate the leaching requirement when electrical conductivity (EC) value of a saturated extract of soil is 10 m mho/cm at 25% reduction in the yield of the crop. The EC of irrigation water is 1.5 m mho/cm.

Estimate the leaching requirement when electrical conductivity (EC) value of a saturated extract of soil is 10 m mho/cm at 25% reduction in the yield of the crop. The EC of irrigation water is 1.5 m mho/cm. Correct Answer 7.5%

The given values are: E.C value of saturated soil = 10 milli-mhos/cm and E.C value of irrigation water = 1.2 milli-mhos/cm. The EC of leaching water is assumed to be twice the EC value of saturation soil extract i.e. = 2 x 10 = 20 milli-mhos/cm L.R = EC of irrigation water / EC of leaching water = 1.5 / 20 x 100% L.R = 7.5%.

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