Biofertilizer are microorganism that helps plants to grow by increasing the quantity of nutrients and mainly associated with the plant rhizosphere. Since these fertilizers contain living microorganisms, it increases or promotes the supply of important nutrients. An increasing number of farmers and agriculturists are turning to the use of biofertilizers, as these are gentler on the soil as against chemical fertilizers. Chemical fertilizers are meant to boost the growth of plants and increase the fertility of the soil; however they cause significant damage to the environment. Biofertilizers helps to restore the natural flora of the soil. Это и многое другое вы найдете в книге Isolation and characterization of bacteria (Muhammad Naeem Iqbal,Naz Mughal and Shahzad Ali)