What are bio-fertilisers? Give two examples.
Organisms which enrich nutrients in the soil are called bio-fertilisers. They restore the soil's nutrient cycle and augment soil organic content. Biofertilizers are imperative for replenishing soil fertility, particularly after chemical fertilizer application that deteriorates soil quality and impacts agricultural productivity. These microbial agents enhance soil's water retention ability and contribute vital elements such as nitrogen, vitamins, and proteins, which are essential for plant growth and nutrition. Azotobacter and Rhizobium are examples of bio-fertilisers.