The agricultural sector is more dynamic nowadays as the urge to feed more sustainably and efficiently continues to increase. One of the most promising developments in this regard has been the introduction and increasing application of biofertilizers. As opposed to the harmful chemical fertilizers, biofertiliser and its constituent microbes serve the purpose of enhancing the soil and productivity of the crops in an environmentally sustainable manner. In this review, biofertilizers and their importance in making modern agriculture more efficient and sustainable with focus on important genera of Rhizobium, Azospirillum, Azotobacter, Acetobacter and Bradyrhizobium focus have been explained.
What Are Biofertilizers?
Biofertilizers are the live microorganisms which enhance soil nutrient content in order to facilitate plant growth. They are also sealer like agents riming the roots of the plants and enabling the nutrients to be found by the soil or water and absorbed by the crops, and consequently yielding more crops. These micro organisms will be able to fix the nitrogen present in the atmosphere, solubilizing the phosphorus present in the soil and promoting the growth of plants by producing growth promoting substances.
Benefits of Using Biofertilizers:
Clean and Environmentally Friendly Approaches: The use of biofertilizers helps in decreasing the use of chemical fertilizers which are detrimental to the soils and pollute water supplies over time.
Cost-effective: Biofertilizers also help farmers to spend less money as they are mostly low priced than the chemical fertilizers.
Boosts Soils Properties: They also help in increasing soil structure and moisture retention capacity in turn improving the nutrients contained within the soil.
Proficient Use of Nutrients by Plants: These techniques also make it possible to assimilate nutrients efficiently through plants, thus enabling proper development and maximum harvests.
Important Biofertilizers and Their Importance
Rhizobium : The Nitrogen Fixer
The bacteria Rhizobium live in symbiosis with leguminous plants like beans and peas. They settle in the root nodules of these plants and fix atmospheric nitrogen, converting it in ammonia form which is readily available for use by plants. This biological nitrogen fixation is essential among legumes crops and helps in decreasing the requirement for synthetic nitrogenous fertilizers.
Azospirillum: Plant Growth Promotor
Azospirillum is an osmophilic biofertilizer capable of root associated nitrogen fixation in cereal crops like wheat, rice, and maize stalks . This non bacterial nitrogen is supplemented by Azospirillum which also releases growth regulating hormones & promoting substances including auxins, cytokinins and gibberellins towards roots of host plants thereby improving the absorption of nutrients & water.
Azotobacter: The Independently Living Wizard
Azotobacter does not need to host plants to grow, it is an aerobic nitrogen-fixing bacterial that lives freely. It is an essential microbial for crops in the fields of non-leguminous crops. As a result of concentrating atmospheric nitrogen among other activities, it increases the nutrient richness of soils and enables the plants to have more growth. It has either antifungal properties and helps in control of certain soil diseases in plants that are helpful in growth of many crops in maize, cotton, vegetables and fruit trees.
Acetobacter: Customized for the Sugarcane
Acetobacter has a great effect on sugarcane production. Studies have shown that this genus of bacteria is capable of fixing atmospheric nitrogen in sugar rich root zones of sugarcane. It helps in promotion of growth as well as the yield of sugarcane, not only by ensuring nitrogen supply, but also by extending root length thereby increasing the ability of the plant to cope with stressful conditions .It can also be used in crops such as sweet potato, and coffee.
Bradyrhizobium: Long Term Partner for the Plant
Bradyrhizobium is another symbiotic nitrogen fixing bacteria, especially partnering in the growth of slow growing perennial legume crops, soy bean, peanuts and some selected trees. Most of the time Bradyrhizobium is associated with legumes like soybean or peanut. In contrast to Rhizobium, Bradyrhizobium has a more prolonged life cycle and can satisfy the nitrogen requirements of its host crop for a long period, leading to better performance of crops with longer rotation periods.
Application Methods of Biofertilizers
Biofertilizers can be applied to crops in a number of ways. Each method is suitable for different agricultural practices:
- Seed treatment: Seeds are coated with biological fertilizer before sowing. This ensures that beneficial bacteria are in close contact with young roots as soon as they emerge.
- Soil treatment : Bio-fertilizer for soil treatment can be mixed directly into the soil. This method is especially effective at breeding bacteria throughout the root zone.
- Root Dipping: Before planting, seedlings can be dipped in a biofertilizer solution to gain immediate access to beneficial bacteria.
- Furrow Application: Suitable for use with rhizobium and bradyrhizobium. This product can be used directly in the planting furrow. This makes it suitable for large scale cultivation.
Future trends in biofertilizers
Considering the increased emphasis on sustainable agriculture .The future of biofertilizers is therefore promising. Advances in biotechnology may lead to the development of more potent and efficient biofertilizer strains. Research is underway to develop biofertilizers that can withstand harsh environments and provide better results. Integrating biofertilizers with other sustainable agricultural practices such as crop rotation and organic farming. It has the potential to expand benefits. Governments and agricultural organizations around the world are beginning to recognize the potential of biofertilizers and support the use of biofertilizers through grants and educational programs.
Stepping towards sustainable agriculture
Biofertilizers are an important step towards sustainable agriculture. By taking advantage of these natural soil improvers. We can grow plants in an environmentally friendly way. Reduce dependency on chemicals and ensuring food security for future generations. Using biological fertilizers such as Rhizobium, Azospirillum, Azotobacter, Acetobacter, Bradyrhizobium .It is not only a tribute to environmentally friendly practices. But it is also a strategic move to increase crop yields and promote long-term soil health. As we innovate and learn more about these amazing microorganism. Potential for greater agricultural change.
