Question

What are bio-fertilizers? Describe their role in agriculture. Why are they preferred to chemical fertilizers?

Answer 1

Fertilizers are the chemical or natural substances that are added to soil to increase the fertility of the soil. Fertile soil is that soil that is rich in nutrients like nitrogen, phosphorous, potassium. Calcium, magnesium, sulfur, iron are some nutrients that we require in small quantities.

Complete answer: Bio fertilizers: They are the living organisms that promote the growth of the plants by replenishing the nutrients in the soil. Bacteria, fungi, and cyanobacteria are the known biofertilizer which increases the nutrients of the soil when we supply them to soil, plant surface, or seeds.
Biofertilizers are added in natural methods like-
1. Nitrogen fixation
2. Solubilizing phosphorus
3. And stimulate the plant growth by growth-promoting substances.
Role of biofertilizers in agriculture:
1. Biofertilizer such as Rhizobium bacteria live in a symbiotic relationship with the plants. They live in root nodules of leguminous plants. These bacteria fix the atmospheric nitrogen and enrich the nitrogen content.
2. Fungi also form a symbiotic relationship with plants by absorbing phosphorus and further pass it to them.
3. Cyanobacteria also fix nitrogen and act as biofertilizer in paddy crops.
Biofertilizers are preferred over the chemical fertilizer due to the following reasons:
1. Biofertilizers are eco-friendly whereas chemical fertilizer cause air, water, and soil pollution.
2. Biofertilizer consists of living organisms whereas chemical fertilizer consists of highly toxic chemicals.
3. Biofertilizers are a natural way of improving the fertility of the soil.

Note: Biofertilizers have been shown to have varying effects in different environments, and even within the same environment. This is something that many scientists have been working on; however, there is no perfect solution at this time. They however have been shown to have the most profound effects in dry climates.