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Microbes as Biofertilisers

Read about the Microbes as biofertilizers, types of microorganisms used as biofertilizers , their advantages and disadvantages

MICROBES AS BIOFERTILIZERS

  • Organic farming is done by natural method without using chemical fertilizers and pesticides.
  • Using microbes in fertilizers will produce crop yields and control all forms of pest attacks and pathogens that eradicate the crops.
  • Microbes used as fertilizers will increase the crop yield and add nutrients to the plant.
  • Microbes such as fungi, bacteria, pathogens, parasites, algae add nutrients to the plant; they can increase the soil nutrients and increase the fertility of the land.
  • Even in laboratory conditions, biofertilizers can be produced to make crop yield. Here are some of the examples of biofertilizers

1) Free-living nitrogen-fixing bacteria such as

  • Azotobacter
  • Rhodospirillum

2) Free-living Nitrogen-fixing bacteria such as

  • Cyanobacteria
  • Anabaena
  • Nostoc

3) Lose association of nitrogen-fixing bacteria like

  • Azospirillum

4) Symbiotic nitrogen-fixing bacteria such as

  • Rhizobium
  • Frankia

WHAT ARE BIOFERTILIZERS?

  • The microorganisms such as bacteria, fungi, algae can increase the soil’s nutrients and promote the plant for growth is called Biofertilizers.
  • Many microorganisms like fungi, bacteria, pathogens, parasites, algae can be used as biofertilizers in different associations, either as symbiotic or non-symbiotic

 

MICROBES USED AS THE BIOFERTILIZERS

TYPES OF BIOFERTILIZERS

There are three types of biofertilizers. They are

  • Bacterial biofertilizers
  • Fungal biofertilizers
  • Algal biofertilizers

BACTERIAL BIOFERTILIZERS

  • Through symbiotic and non-symbiotic or with roots, bacteria promote soil fertility and increase plant yield.
  • Bacteria supply free nitrogen components and fix the free nitrogen in the soil.
  • For example, Rhizobium, Azospirillum, Azotobacter, Phosphobacteria fixes the free nitrogen into nitrogen compounds like ammonia, nitric acid, organic nitrates, etc.
  • Even cyanobacteria such as Anabaena, Nostoc, and Aulosira can fix nitrogen in the soil.
  • Actinomycetes can promote plant growth. Actinomycetes also help in fighting against plant disease by producing many secondary metabolites.
  • Frankia help in increasing agricultural production

FUNGAL BIOFERTILIZERS

  • Some fungi maintain a mutual association with plants and provide nutrients such as Trichoderma and Mycorrhizal fungi.
  • The primary role of fungi as micro fertilizers is to keep up the plant’s health, enhance soil fertility and increase productivity.

ALGAL BIOFERTILIZERS

  • organic framing Some of the widely used algal biofertilizers are blue-green algae(BGA) and Azolla
  • The above-mentioned algal biofertilizers are cultured in mass quantity.
  • Many biofertilizers can be cultured in the laboratory, so we can say the microorganisms produced in a laboratory for accessible applications are called biofertilizers.

HOW ARE BIOFERTILIZERS ARE IMPORTANT?

  • Save for environment, user friendly, does not  harm any living organisms
  • Bioferilters main motto is to increase soil yield and to increase productivity
  • Many organic farmers can inject these biofertilizers into the plant to increase productivity
  • promotion of growth and creation of crops
  • It can be used in any arid and semi-arid regions

 

MICROORGANISMS USED AS BIOFERTILIZERS

Here are some of the examples of Microbes as biofertilizers

  • Rhizobium
  • Azospirillum
  • Azotobacter
  1. Blue-green Algae
  2. Mycorrhiza
  3. Phosphate solubilizing microorganisms

RHIZOBIUM

  • Most effective and widely used microorganisms are mainly associated with leguminous plants. And it fixes nitrogen in the form of nitrogen components such as ammonia in the plants.
  • Rhizobium bacteria have a symbiotic association with leguminous plants form root nodules to fix nitrogen in the plant.
  • If more the number of legume plants then more is the number of rhizobium

AZOSPIRILLUM

perform symbiotic association with higher plants like 

(i)sorghum

(ii) maize, 

(iii)millets, and 

(iv) also fodder grasses

by producing antibodies to fix nitrogen in the plants

  • The growth condition for azospirillum is a wetland with a pH of 6. It works well in this particular pH

Azotobacter

  • It can’t grow in wetland conditions and it needs land with minimum fertility
  • It is one of the free-living organisms in the root to provide nutrients, increase fertility and increase crop yields

BLUE-GREEN-ALGAE

  • It is free-living in many colors, such as red, brown, purple, and found in damp and marshy areas.
  • They are abundant in the rice field to fix the nitrogen in the soil
  • It may be filamentous and consist of heterocyst, which is considered the place for nitrogen synthesis and production.
  • The main drawback of these bacteria is they can’t survive in acidic conditions.

MYCORRHIZA

  • Its essential function is binding the soil particles and microbial activity and performing symbiotic association with fungus and plant roots.
  • VAM(vesicular Arbuscular Mycorrhiza) develops hyphae. VAM is also the reason for an increase in the rhizosphere
  • The growth and yield of the crops can be by the symbiotic relationship of VAM. It has a symbiotic relationship between roots and fungi.
  • It is widely used in commercial and organic farming.
  • Some fungi can grasp the nutrients from organic matter. Example – mycorrhizal
  • It helps the plants from pathogens by creating antibiotics such as HCN and some secondary metabolisms.

MICROBES IN BIOFERTILIZERS

We can say many points to list out the advantages and disadvantages of biofertilizers

ADVANTAGES OF BIOFERTILIZERS

  • Using biofertilizers can increase the plant yield by 15-35%. Biofertilizers are sustainable and not polluting in nature.
  • They are available at an affordable cost and at the same time increase the plant yield.
  • It helps fix the nitrogen present in symbiotic or non-symbiotic associations.
  • It can be used in any soil condition, but there are some exceptions. It reduces soil pollution and causes no harm to humans.

DISADVANTAGES OF BIOFERTILIZERS

  • The biofertilizer can get contaminated during large scale production, but this might not happen during small scale
  • Biofertilizers also increase the plant yields up to 20-30%, but it is less compared to chemical fertilizers
  • The Microbe biofertilizers should be stored at room temperature to increase the lifetime of the biofertilizers
  • Sometimes these biofertilizers can’t be used in high wetland ph and acidic conditions of the soil
  • Lack of storage and technical experts are the main disadvantages of biofertilizers

Conclusion-

Microbes used as fertilizers will increase the crop yield and add nutrients to the plant.Microbes such as fungi, bacteria, pathogens, parasites, algae add nutrients to the plant; they can increase the soil nutrients and increase the fertility of the land.Even in laboratory conditions, biofertilizers can be produced to make crop yield. Here are some of the examples of biofertilizers.