Bio in Biofertilisers means fertiliser made up of biological organisms, mainly bacteria. The main property of fertiliser is to increase the soil’s nitrogen content, which improves the growth and productiveness of the crop, and for that, we use chemicals that are harmful to crops and other plants. However, nowadays, we are slowly moving towards biofertilisers. These fertilisers fertilise soils using microorganisms, but how does this microorganism act like a fertilising agent? We need to know the basic concept in biology known as symbiosis. This is a relationship between two different organisms in ecology or ecosystem where both organisms are benefited. For example, there is a plant, and bacteria reside in the plant’s root as both of the organisms are benefited, so the plant supplies all the nutrients to the bacteria. In return, bacteria help fix nitrogen from the air into the soil, and that nitrogen provides nutrition to the plant for their growth. Biofertilisers increase the number of bacteria, which in exchange increase the soil’s nitrogen content. Some examples of these bacteria are cyanobacteria, endophytes and rhizobacteria.
Biofertilisers are good for the environment as well.
Production of Biofertilisers
First, we need to make the starter culture, which is made up of the type of bacteria we want to produce this fertiliser. Then we transfer them into a broth, then we transfer it in a considerable container containing soil and water where fertilisation takes place, and after sometimes it will form a substantial bacterial mass (forms a mat-like structure) on top of the soil which is then cleaned and after that drying is done then it is served as powder. The procedure mentioned above is mainly industry-based, but we can also make our Biofertilisers at home, basically known as compost. For preparing compost, we need a container filled with soil in which we add peels of fruits and vegetables or waste flowers, then cover it with soil or dry leaves and leave it for two to three months now the compost is ready for use.
Types of Biofertilisers
Rhizobium
Rhizobium is a particular bacteria that can live in the soil or root nodule of the leguminous plant. Rhizobium forms a symbiotic association with legume plants obtaining nutrients from the plants and producing nitrogen in biological nitrogen fixation. This Rhizobium has a nitrogen fixation capacity of 40-250 N/hac per year.
Azotobacter
These nitrogen-fixing free-living aerobic bacteria can fix atmospheric nitrogen in non-leguminous plants. Besides fixing nitrogen, they also increase germination leading to improved crop breed. They can fix 50-20kg N/hac per year. Azotobacter species also can produce antifungal compounds against many plant pathogens.
Azospirillum
Azospirillum is a bacteria that fix nitrogen in non-leguminous plants like cereals, sunflower, carrot, millets, cotton etc. It can fix 20-40 kg N/ha in the rhizosphere. The crop aid can increase from 5-30%.
Plant Growth Promoting Rhizobacteria(PGPR)
Various bacteria that promote plant growth are collectively called Plant Growth Promoting Rhizobacteria(PGPR). They improve plant growth by colonising the root. PGPR are of many types, few are pseudomonas, bacillus, rhizobium etc.
Phosphorus-solubilizing bacteria
Phosphorus is a vital nutrient next to nitrogen for plants and microorganisms. Bacteria and fungi are very beneficial to the plant, and phosphorus is available to the plants by these PSBs. It can increase profit up to 200-500 kg/ha.
Blue-green algae
Blue-green algae are microscopic living autotrophic organisms capable of building up food materials from inorganic methods. Certain blue-green algae live intimately with other organisms in a symbiotic relationship; some are associated with fungi in the form of lichens. They can photosynthesize food and fix atmospheric nitrogen, which is very useful in paddy fields.
Application of Biofertilisers
Seed treatment
In seed treatment, seeds are kept in a mixture of nitrogen and phosphorus with water and then dried. When it dries out, it is sown as soon as possible so that it does not get infected by other microorganisms.
Seedling root dip
In this method, the seedlings are planted in a water bed for eight to ten hours and then planted. This method applies to mainly rice crops.
Soil Treatment
This treatment mixture of all fertilisers and compost is kept for one whole night. This mixture is then spread over the soil, where seeds are sown.
Benefits of Biofertilisers
1) Biofertilisers increase the crop’s yield from 10 to 40% by using microorganisms which makes soil rich and fertile. It can increase seed germination up to 20% when treated, improving seedling emergence and growth.
2) Rather than focusing only on quantity, it focuses on quality. Biofertilisers use natural components which do not harm plants and enhance the quality and shelf-life of fruits and vegetables.
3) In terms of soil health, Biofertilisers are best as it is free from chemicals and there is no side effect on the soil at a later stage. If the soil is free from chemicals, it will retain its fertility with time and protect the soil from getting polluted.
4) Biofertilisers are safe for the environment as they do not release any harmful chemical that directly impacts health and the environment. In contrast, chemical fertilisers release harmful chemicals which pollute the local land and water sources and lead to many diseases.
5) Biofertilisers are inexpensive and easy to use, so poor farmers can also use them. Compost can also be prepared at home from the waste peels of fruits and vegetables or food scraps, which also helps waste management.
Conclusion
Due to rapid population increase, we are highly dependent on chemical fertilisers, which are hazardous for human consumption, and disturb ecological balance by polluting land and ever-decreasing soil fertility. These chemical fertilisers are the reasons for many diseases like cancer, which is essential for people shifting toward organic farming. We can blend Biofertilisers with modern farming techniques to tackle this problem as it increases crop productivity without polluting the soil and water resources. This method is cost-effective and easy to use, which also helps in waste management.