There are at least eighteen chemical elements which are essential for the growth and development of all plants. Out of these, carbon (C) hydrogen (H) and oxygen (O) are obtained by plants through air and water and the rest through soils. fertilisers and manures. Fertiliser application does not worry about C, H or O but the remaining 15 mineral nutrients are of interest in one way of the other (Table 1). The second column in Table I gives the nutrient element′s symbol. These symbols are used in chemistry but have now become very convenient short names. The third column gives the forms in which nutrients are absorbed by plant roots. Thus NH + (ammonium ion) and NO – (nitrate ion) are forms in 4 3 which plants absorb N. The last column gives average nutrient concentration in a plant.