Nitrogen = N

Is a chemical element represented by the N symbol, consist of 78% by volume of the earth atmospheres. 

The main component of earth’s atmosphere “Most widely distributed in nature, a Key elements present in many compounds of plant cells and occurs in all living organisms. Is relatively inert substance. 

That is to be useful must be converted into active form. It is an essential element, Required in highe a mount In terms of quantity in the phytomass, it is 4th among the bioelements, after C, O and H. Very mobile elements, circulating between atmosphere, soil and living organism. ¨   Soil is the main source for plant nitrogen. From the soil N, only very small proportion is directly available to plants, as N03¯ and NH4+ ,Nitrogen also released from plants in the form of organic compound ¨ Availability Main forms of inorganic compounds are: Nitrates (NO3-), Nitrites (NO2-) & ammonium (NH4+)