How microbes are used as biofertilizers

Biofertilizers are increasingly preferred over harmful chemicals according to MarketWatch. Between 2018 – and 2025, there’s a forecast that the rate at which biofertilizers will be used by farmers to increase the fertility of soil and crops is going to increase.

In the world of agriculture, where soil health and nutrient availability are paramount, the use of fertilizers has long been a cornerstone of crop production.

However, the environmental and economic costs associated with traditional chemical fertilizers have led to a growing interest in sustainable alternatives.

Among these alternatives, biofertilizers, particularly those involving microbes, have gained prominence.

In this comprehensive guide, we will explore the fascinating realm of how microbes are used as biofertilizers to enhance soil fertility, crop yields, and the overall sustainability of agriculture.


As the global population continues to expand, the pressure on agriculture to meet the rising demand for food grows exponentially.

Traditional agriculture heavily relies on chemical fertilizers to enhance soil fertility and boost crop yields.

However, this approach comes with several drawbacks, including soil degradation, nutrient runoff, and environmental pollution.

In response to these challenges, biofertilizers have emerged as a sustainable and environmentally friendly alternative.

Biofertilizers, often referred to as “biological fertilizers,” are a category of fertilizers that contain living microorganisms, mainly beneficial bacteria, fungi, or archaea.

Unlike chemical fertilizers, which directly provide plants with essential nutrients, biofertilizers work in symbiosis with plants and soil microorganisms to enhance nutrient availability.

This cooperative relationship between plants and microbes has revolutionized modern agriculture by promoting soil health and reducing the negative impacts associated with conventional fertilizers.

What are biofertilizers?

Biofertilizers are plant growth enhancers. They are substances that contain living microorganisms like bacteria, this substance is then applied to plant surfaces, seeds, or soil to promote plant growth either by increasing the supply of nutrients to the plant or by stimulating plant growth-promoting substances.

For instance, the blue-gree alga is a biofertilizer that can be helpful to fix atmospheric nitrogen in the soil.

What are chemical fertilizers?

How microbes are used as biofertilizers

Whenever you hear “chemical”, it oftentimes means a considerable amount of synthetic compound substances. In this case, chemical fertilizers are chemical substances specially created to increase crop yield.

These nutrients, including nitrogen (N), phosphorus (P), and potassium (K), are vital for plant growth and development. Traditionally, chemical fertilizers have been the primary source of these nutrients.

Chemical fertilizers, while effective at boosting crop yields, have several drawbacks. One of the most significant concerns is their potential to harm the environment.

When excessive amounts of chemical fertilizers are applied to fields, the excess nutrients can leach into groundwater or run off into nearby water bodies.

This nutrient runoff can lead to water pollution, including harmful algal blooms and the creation of oxygen-depleted “dead zones.”

Additionally, the continuous use of chemical fertilizers can degrade soil quality over time. It disrupts the natural nutrient cycling processes in the soil and can result in soil acidification and nutrient imbalances.

This soil degradation can lead to reduced crop productivity and the need for even greater fertilizer inputs, creating a vicious cycle.

Related: Microbial Journals

Types of Biofertilizers

Biofertilizers are a sustainable and environmentally friendly alternative to chemical fertilizers. They contain living microorganisms that establish a beneficial relationship with plants and soil, improving nutrient uptake and soil health. There are several types of biofertilizers, each with its specific functions:

  • Nitrogen-Fixing Biofertilizers: These contain nitrogen-fixing bacteria, such as Rhizobium and Bradyrhizobium, which form symbiotic relationships with leguminous plants. They convert atmospheric nitrogen into ammonia, providing a direct and sustainable source of nitrogen to plants.
  • Phosphate-Solubilizing Biofertilizers: These biofertilizers consist of phosphate-solubilizing microorganisms, such as Pseudomonas and Bacillus species. They secrete enzymes and organic acids that solubilize insoluble phosphate in the soil, making it available for plant uptake.
  • Potash-Mobilizing Biofertilizers: Potassium (K) is essential for plant nutrient uptake and overall health. Potash-mobilizing bacteria, like Bacillus and Clostridium species, enhance the availability of potassium by releasing it from mineral sources in the soil.
  • Mycorrhizal Biofertilizers: Mycorrhizal fungi form symbiotic relationships with plant roots and enhance nutrient absorption, especially phosphorus. They extend the reach of plant roots by forming a network of hyphae that can access nutrients beyond the plant’s root zone.

The use of biofertilizers in agriculture represents a paradigm shift towards sustainable and eco-friendly farming practices. These living microorganisms harness the power of nature to enhance soil fertility and crop productivity while mitigating the negative impacts associated with chemical fertilizers.

Microbes as Biofertilizers

Microbes are at the forefront of the biofertilizer revolution, offering innovative solutions to enhance soil fertility and crop productivity. Let’s explore some key microbial players in the realm of biofertilizers:

1. Nitrogen-Fixing Bacteria

Nitrogen is an essential nutrient for plant growth, and nitrogen-fixing bacteria play a crucial role in making atmospheric nitrogen available to plants in a usable form.

They convert atmospheric nitrogen (N2) into ammonia (NH3) through a process called nitrogen fixation. This conversion is vital because plants can’t directly utilize atmospheric nitrogen.

One of the most well-known examples of nitrogen-fixing bacteria is the genus Rhizobium, which forms symbiotic relationships with leguminous plants like soybeans, peas, and clover.

These bacteria reside within nodules on the plant’s roots and convert atmospheric nitrogen into ammonia, which the plant can access for its growth. This remarkable symbiosis reduces the need for synthetic nitrogen fertilizers and benefits both the plant and the soil.

2. Phosphate-solubilizing microbes

Phosphorus is another vital nutrient for plants, but it often exists in insoluble forms in soil, making it less accessible to plants. Phosphate-solubilizing microbes, such as species of Pseudomonas and Bacillus, play a significant role in unlocking this essential nutrient.

These microbes secrete enzymes and organic acids that break down insoluble phosphate compounds in the soil, converting them into soluble forms that plants can absorb through their roots. By improving phosphorus availability, phosphate-solubilizing biofertilizers enhance plant growth and overall crop yield.

3. Potash-Mobilizing Bacteria

Potassium (K) is critical for plant nutrient uptake and overall health. Potash-mobilizing bacteria, including species from the Bacillus and Clostridium genera, are instrumental in enhancing the availability of potassium in the soil.

These bacteria possess the ability to release potassium from mineral sources in the soil by solubilizing potassium-containing minerals. This mobilization of potassium ensures that plants have a readily available source of this essential nutrient, promoting healthy growth and improved crop quality.

Benefits of Using Microbes as Biofertilizers

The utilization of microbes as biofertilizers offers several compelling advantages for sustainable agriculture:

1. Improved Nutrient Availability

Microbes enhance nutrient availability by fixing atmospheric nitrogen, solubilizing phosphorus, and mobilizing potassium. This results in healthier plants with increased resistance to stress and disease.

By harnessing the power of beneficial microorganisms, farmers can reduce their reliance on synthetic fertilizers while achieving comparable or even superior crop yields.

This shift towards biofertilizers contributes to more sustainable and environmentally friendly farming practices.

2. Enhanced Soil Health

Biofertilizers not only provide nutrients to plants but also foster soil health and resilience. These living microorganisms promote beneficial microorganisms in the soil, suppress harmful pathogens, and increase the organic matter content.

A healthier and more biologically active soil environment improves soil structure, water retention, and nutrient cycling.

Over time, this leads to enhanced soil fertility and reduced soil degradation, benefiting both current and future generations of crops.

3. Environmental Sustainability

Compared to chemical fertilizers, biofertilizers offer a more sustainable approach to agriculture. They reduce the risk of nutrient runoff and groundwater contamination, helping protect water quality in nearby ecosystems.

Additionally, the production and transportation of chemical fertilizers are energy-intensive processes that contribute to greenhouse gas emissions.

Biofertilizers, on the other hand, have a lower carbon footprint, making them a greener choice for environmentally conscious farmers.

As agriculture continues to evolve towards more sustainable practices, microbial biofertilizers will undoubtedly play a central role in nourishing our growing global population while preserving our planet’s precious resources.

Embracing the microbial power of biofertilizers is not just a choice; it’s a step towards a greener, more sustainable future for agriculture.

Is biofertilizer better than chemical fertilizer?

Without wasting much time, I will quickly agree that biofertilizers are better than chemical fertilizers because;

  • They are eco-friendly and thus are not harmful to the environment just as in the case of chemical fertilizers.
  • Contrary to popular opinion, a recent study has proven that microorganisms have an association with plant roots thereby leading to enhanced growth and production. 
  • Therefore, biofertilizers once applied to plants enhance the microbes and plant root relationship while chemical fertilizers would not.
  • Applied chemical fertilizer can chemically infest plant products which is not the same for biofertilizers.
  • Biofertilizers are cost-effective compared to chemical fertilizers.

Classification of biofertilizers according to organisms

They are classified according to their function and the microorganism responsible for that function.

  • Bacteria biofertilizers
  • Fungal biofertilizers
  • Algal biofertilizers
  • Actinomycetes biofertilizers

Biofertilizer production

Microbes are used as biofertilizers by a process known as fermentation therefore they are not directly applied to plant seeds, roots, or soil. Without this process, it would be impossible for microbes to become fertilizers.

The process must have these factors in place;

  • Selected microbial strain
  • Its cultivation in an appropriate nutrient media
  • Plant specificity of the microbial strain
  • Properties of soil
  • Environmental conditions.

All of these processes are carried out in the lab with similar conditions as they relate to the environment or the field.


In conclusion, the use of microbes as biofertilizers represents a promising avenue for sustainable agriculture.

These microscopic allies play a vital role in enhancing nutrient availability, improving soil health, and reducing the environmental impact of farming.

As agriculture continues to evolve towards more sustainable practices, microbial biofertilizers will undoubtedly play a central role in nourishing our growing global population while preserving our planet’s precious resources.

Embracing the microbial power of biofertilizers is not just a choice; it’s a step towards a greener, more sustainable future for agriculture.

Other articles you might like

Last Updated on September 20, 2023 by Our Editorial Team

Leave a Comment