Fertilizer : Any natural or manufactured solid or liquid material, added to the soil to supply one or more nutrients essential for the proper development and growth of a plant is called a fertilizer. Fertilizers, in the broadest sense, are products that improve the levels of the available plant nutrients and/or the chemical and physical properties of the soil, thereby directly or indirectly enhancing the growth, yield and quality of the plant. The term is
generally applied to commercially manufactured materials other than lime or gypsum. (The Fertilizer Encyclopedia, 2009).
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