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Manures are rich in organic matter but are poor supplier of nutrients. So, the cultivated field which is not supplied with fertilizers may suffer from the deficiency of nutrients and not give very good yield.

The cultivated field which is supplied with fertilizers only may face drainage problem and water logging due to lack of organic matter in the soil. This may harm the crop and the yield. Use of fertilizers over long periods of time can destroy the soil texture by killing the microorganisms that recycle nutrients in the soil.