Question

What are Biofertilizers? Give some examples.

Answer 1

Hint: Bio means living organisms and fertilizers means those compounds that are used to increase the growth and development of plants and increase the crop yield.

Complete Answer:
- Biofertilizers are those fertilizers that contain microbes which are used for promoting the growth of plants. This is done by increasing the supply of nutrients that are essential for the growth of plants. The microbes that are used in biofertilizers can be bacteria, some blue green algae and mycorrhizal fungi.
- Cyanobacteria help in nitrogen fixation and provide plants with fixed nitrogen which can be readily used by plants. Additionally, fungi like micorriza withdraw minerals from the organic matter and supply it to the plants thus helping them in growth. Bacteria on the other hand convert the insoluble forms of phosphorus in soil to the soluble form which can be easily taken up by the plants.
- Biofertilizers are of different types. Symbiotic nitrogen fixing bacteria like rhizobium live in a symbiotic relationship with plants in which they provide plants with fixed nitrogen and seek shelter and food from plants in return.
- Loose association nitrogen fixing cyanobacteria like liverworts, cycad roots, fern and lichen live in symbiotic association with plants and are responsible for nitrogen fixation. Free living nitrogen fixing bacteria include azotobacter. Among all types of biofertilizers the most widely used biofertilizers are rhizobium and azospirillum.

Components of biofertilizers include:
1. Compost - Which is a eco friendly product made up of waste material released from industries
2. Azotobacter - It protects the roots from pathogens which are present in soil and helps in nitrogen fixation.
3. Phosphorus - Essential nutrient for the growth and development of plants
4. Vermicompost - It is an organic fertilizer which contains hormones, antibiotics, sulfur and helps increase crop yield and quality.

Biofertilizers are important because they improve the texture of soil and yield of the plants. They are eco friendly and do not cause any harm to the environment. Additionally, they are cost effective and do not allow unwanted microbes to grow.

Note: They are a great alternative to chemical fertilizers and thus helps reduce pollution which is caused by the harmful effects of the chemical fertilizers. Chemical fertilizers also sometimes kill the useful microbes which is not possible in biofertilizers making them more beneficial to use.