Biofertilizer use for sustainable agricultural production

Abstract

The economic and environmental costs of the indiscriminate use of chemical nitrogenous fertilisers in agriculture are a global concern. Sustainability considerations mandate that alternatives to nitrogen fertilisers must be urgently sought. Biological nitrogen fixation (BNF), a microbiological process which converts atmospheric nitrogen into a plant-usable form, offers this alternative. Nitrogen-fixing systems offer an economically attractive and ecologically sound means of reducing external inputs and improving internal resources. Symbiotic systems such as that of legumes and rhizobium can be a major source of nitrogen in most cropping systems and that of Azolla and A nabaena can be of particular value to flooded rice crop. Nitrogen fixation by associative and free-living microorganisms can also be important. Bio-fertilisers generate plant nutrients like nitrogen and phosphorous through their activities in the soil or rhizosphere and make available to plants in a gradual manner. Bio-fertilisers are gaining momentum recently due to the increasing emphasis on maintenance of soil health, minimise environmental pollution and cut down on the use of chemicals in agriculture that will lead to sustainable agricultural production.