Organic matter decomposition serves three functions for the micro flora: (i) providing energy for growth, (ii) supplying carbon for the formation of cell material, and (iii) providing other nutrient, elements needed for cell growth. Microorganisms vary significantly in terms of the source, chemical form, and amount of essential elements they need. Some examples of these essential nutrients are carbon, oxygen, hydrogen, phosphorus, and sulfur. Microorganisms require macronutrients, micronutrients and growth factors, for their growth. Microorganisms require macronutrients, micronutrients and growth factors, for their growth. These nutrients help in constructing the cellular components like proteins, nucleic acids and lipids.Effective microorganisms enhance soil fertility and promote growth, flowering, fruit development and ripening in crops. It can increase crop yields and improve crop quality as well as accelerating the breakdown of organic matter from crop residues

All microbes have a need for three things: carbon, energy, and electrons. There are specific terms associated with the source of each of these items, to help define organisms. Microorganisms play an important role in the acquisition and transfer of nutrients in soil. In particular, microorganisms can solubility and mineralize P from inorganic and organic pools of total soil P. The primary decomposers (bacteria and fungi) release extracellular hydrolytic enzymes into their immediate environment and these catalyze organic matter decomposition. They require carbon, hydrogen, oxygen, nitrogen, metals and water for their biochemical processes. On the basis of their energy source and the carbon, bacteria are divided into two major classes: autotrophs and heterotrophs. Decomposers play a critical role in the flow of energy through an ecosystem. They break apart dead organisms into simpler inorganic materials, making nutrients available to primary producers. Microbial growth requires suitable environmental conditions, a source of energy, and nourishment. These requirements can be divided into two categories, physical and chemical.