Biological alternates to synthetic fertilizers: efficiency and future scopes

The nutrient availability to plants is major limiting factor determining the crop production. Chemical fertilizers are, no doubt, a milestone to fulfill the nutrient deficiency but presently mankind is facing a huge threat of environment damage as well as resource depletion. At the same time population explosion is also a major concern. To feed such a large population (8.5 × 109 in 2025) unexploited resources should be used to enhance the crop production and to improve quality of soil. The various plant specific nitrogen fixing, phosphate solubilizing, potassium solubilizing and zinc mobilizing microorganisms can be used to enhance the bioavailability of nutrients to plants. This biological method is not only sustainable for long run but also economical and thus can be used as biofertilizers. These microorganisms can be commercially made available to farmers in the form of carrier based, liquid or encapsulated formulations containing latent or active forms. Apart from nutrient mobilization, they can also act as bioenhancers and biopesticides. However, efficiency and acceptance of biofertilizer among farmers is still a big concern. This review article focuses on efficiency of biofertilizers to replace or supplement the synthetic fertilizers for soil fertilization.