The Attributes of Biofertilizer as an Alternative to Chemical Fertilizer: A Mini Review

Abstract

Traditional soil management relies heavily on inorganic fertilizers, raising environmental and health concerns. A fertile soil requires a precise ratio of inorganic and organic components, with topsoil crucial for plant growth. Essential plant elements include macronutrients (nitrogen, phosphorus, potassium) and micronutrients (zinc, iron). Soil composition must balance minerals, air, water, and living matter. Macronutrients (nitrogen, phosphorus, potassium) are pivotal in plant growth. Potassium influences water regulation, root development, and crop resilience. Phosphorus, crucial for seed development, is essential for legume development. Nitrogen from nitrates, ammonium, and urea is indispensable for protein synthesis and overall plant growth. Biofertilizers, containing active microorganisms, offer an alternative to inorganic fertilizers. They enhance soil fertility, water and nutrient uptake, and plant tolerance to environmental variables. Nitrogen-fixing bacteria, phosphate solubilizing microorganisms (PSM), silicate solubilizing bacteria (SSB), plant growth-promoting rhizobacteria (PGPR), and arbuscular mycorrhizal fungi (AM fungi) are common groups of bacteria that play different specific roles in defining biofertilizer. Bacterial genera such as Rhizobium (a symbiotic nitrogen fixer known for forming nodules on legumes), Azotobacter (a free-living nitrogen fixer known for enhancing sugar content in crops), Azospirillum (a bacterium known for enhancing nitrogen content in non-leguminous plants) and Anabaena-Azollae (a symbiotic relationship between a cyanobacterium and lower plants known in fixing nitrogen and promotes growth in various crops). As agriculture continues to evolve, embracing biofertilizers represents a promising step toward a more sustainable and resilient future.