Biofertilizers are natural supplements, derived from beneficial microorganisms, such as bacteria, fungi and algae, or their derivatives. These microorganisms establish symbiotic or associative relationships with plants, promoting nutrient uptake, protecting against diseases and enhancing overall plant growth. They enhance nutrient levels in the soil by harnessing natural processes such as nitrogen fixation, phosphorus solubilization and the synthesis of growth-promoting substances, thereby promoting plant growth. With their ability to enhance crop productivity and reduce chemical dependency, biofertilizers play a vital role in promoting sustainable and eco-friendly agricultural systems.  Types of Biofertilizers: Types of Biofertilizers  Examples  N2 fixing Biofertilizers  Free-living  Azotobacter, Clostridium, Beijerinkia, Anabaena, Nostoc  Symbiotic  Rhizobium, Frankia, Anabaena azollae  Associative symbiotic  Azospirillum  P Solubilizing Biofertilizers  Bacteria  Bacillus subtilis, Bacillus megaterium, Bacillus circulans, Pseudomonas striata  Fungi  Penicillium sp, Aspergillus awamori  P Mobilizing Biofertilizers  Mycorrhizal Fungi  Glomus sp., Rhizoctonia solani., Acaulospora sp., Scutellospora sp., Gigaspora sp., Sclerocystis sp  Biofertilizers for Micronutrients  Silicate and Zinc (Zn) solubilizers  Bacillus sp  Plant Growth Promoting Rhizobacteria (PGPR)  Pseudomonas   Pseudomonas fluorescens    Why are Biofertilizers Important in Agriculture?  Biofertilizers enrich the soil by improving its microbial activity, organic matter content, and nutrient availability, leading to sustainable soil health.  They enhance nutrient uptake efficiency by facilitating the release of nutrients from the soil and promoting their absorption by plant roots.   They are environmentally friendly which reduces the dependency on synthetic fertilizers.  Compared to synthetic fertilizers, they can be cost-effective in the long run as they improve soil fertility, reducing the dependency on expensive chemical inputs.  Certain biofertilizers possess beneficial microorganisms that suppress soil-borne diseases by inhibiting the growth of pathogens, reducing the need for chemical fungicides. For example: Bacillus subtilis inhibits the growth of pathogens like Botrytis, Phytophthora, and Alternaria, providing disease suppression in crops such as vegetables, fruits and ornamentals.   They can improve overall crop yield by 10 – 25%.  Biofertilizers contain beneficial microorganisms that can help plants withstand biotic and abiotic stresses.  They contribute to improved soil structure and stability, reducing the risk of soil erosion.  Methods of Biofertilizer Application: Biofertilizers can be applied through various methods depending on the type of biofertilizer, the crop being grown, and the specific agricultural practices.  Seed Treatment: Biofertilizers can be applied directly to the seeds before planting by coating the seeds with a biofertilizer formulation or by soaking the seeds in a biofertilizer solution before planting.  Seedling / Root Dip: In this method, roots of the seedlings or transplants are dipped in a biofertilizer suspension before transplanting them into the main field.  Soil Application: Biofertilizers can be applied to the soil either during or before planting. The products can be mixed with soil amendments like well decomposed FYM / compost / organic matter and can be spread evenly across the field. It can also be applied in furrows or planting holes at the time of sowing or transplanting.  Drip Irrigation or Fertigation: Biofertilizers can be applied through drip irrigation systems, by injecting its solution directly into the irrigation system, allowing it to be distributed evenly throughout the field.   Foliar Application: Some biofertilizers can be applied as foliar spray onto the leaves of plants. It involves spraying diluted biofertilizer solution onto the foliage, allowing the plant to absorb the nutrients and beneficial microorganisms through the leaf surfaces. This may help to address specific nutrient deficiencies.   Composting or vermicomposting: Biofertilizers can also be incorporated into the composting or vermicomposting process. This will help in decomposition of organic materials, accelerating the composting process and enriching the compost.  Biofertilizers and the crops on which it is used: Biofertilizer  Crops Commonly Used On  Rhizobium  Legumes (e.g., soybean, chickpea, lentils, groundnut)  Azotobacter  Cereals (e.g., wheat, rice, maize), vegetables, cotton, spices, tobacco, ornamental flowers  Azospirillum  Cereals, millets, oilseeds, vegetables  Phosphobacteria  Cereals, oilseeds, pulses, vegetables, sugarcane, fruits and flowers  Blue Green Algae (Cyanobacteria)  Paddy, banana  VAM (Mycorrhizae)  Various crops for enhanced nutrient uptake  Phosphate solubilizing bacteria and fungi  All crops  Azolla  Paddy    Find the perfect biofertilizers for your farming needs at BigHaat!   Product  Technical content  Method of Application  Dosage  Premium Azospi  Azosprillium  Seed Treatment  4 – 5 ml/50 – 100 ml of water  Seedling Dip  4 – 5 ml/lit of water  Soil Application  500 ml – 1 lit of product + 40 – 50 kg FYM/compost  Drip Irrigation  5 – 10 ml/lit of water  Sun Bio Rhizo Bio Fertilizer  Rhizobium  Seed Treatment  Mix 10 ml of the product in cold jaggery solution and then apply  Seedling Dip  10 ml/lit of water  Soil Application  1 lit of the product + 50 – 100 kg of FYM/compost  Drenching  5 – 10 ml/lit of water  Drip Irrigation  Amruth Azotofix Liquid  Azotobacter sp  Seed treatment  2 – 3 ml/lit of water  Drip Irrigation  Soil Application  2 ml/lit of water (Individual plants)  Biofix Ajay Potash  Potasssium mobilizing biofertilizer  Seed Treatment  4 ml/kg of seeds  Seedling Dip  10 ml/lit of water  Drip Irrigation  15 – 25 ml/lit of water  SUN BIO POTASH  Potash Mobilizing Bacteria    Seed Treatment  10 ml of product + cold jaggery solution  Seedling Treatment  10 ml/lit of water  Soil Application  1 lit of product + 50 –100 kg of well-decomposed manure or cake  Drenching  5 – 10 ml/lit of water  Fertigation  Vamlet Biofertilizer  Vesicular Arbuscular Mycorrhizae  Soil Treatment  4 kg of the product + 50 kg of FYM/compost  Kan Biosys Phosfert  Phosphate solubilizing strains of Azotobacter chroococcum and Bacillus polymyxa  Soil Application / Fertigation  2.5 ml/lit of water  Kan Biosys Vitormone   Azotobacter  Foliar spray  2 ml/lit of water  Symbion-K  Frateuria sp– Potash solubilizing / mobilizing bacterium  Seed Treatment  10 ml/kg of seeds  Seedling Dip  10 ml/lit of water  Sett Treatment  Soil Treatment  1.2 lit/acre of the product + 200 kg of manure  Drip Irrigation  5 ml/lit of water  Biofix AJAY AZO SF  Bio-fertilizer based on Azotobacter species  Seed Treatment  3 ml/kg of seeds  Seedling Dip  10 ml/lit of water  Drip Irrigation  10 – 15 ml/lit of water  Ajay Biotech Sphurda SF  Bio-fertilizer containing phosphate solubilizing micro-organisms (PSBs)  Seed Treatment  4 ml/kg of seeds  Seedling Dip  10 ml/lit of water  Drip Irrigation  3 – 5 lit per acre    Precautions to be taken while using Biofertilizers:  Should be stored in a cool, dry place away from direct sunlight to maintain the viability of the living microorganisms.  Apply biofertilizers at the appropriate stage of crop growth or as recommended.  Follow the recommended dosage guidelines. Avoid excessive application, as it may lead to imbalances in nutrient levels or interfere with plant growth.  Avoid applying biofertilizers during hot, dry periods or under intense sunlight, as this may reduce their effectiveness.  Prevent contamination of biofertilizers during handling and application.  Adequate soil moisture is crucial for the survival and activity of biofertilizer microorganisms. Ensure that the soil has sufficient moisture content before and after applying biofertilizers.  Biofertilizer, fungicides and other chemicals are incompatible, therefore they should not be mixed together.  To maximize effectiveness, it is recommended to exclusively apply Rhizobium to the designated crops due to its crop-specific nature.  Use the packet or bottle before its expiry.  Use both nitrogenous and phosphatic biofertilizers in combination to get optimal outcome.  Do not mix the bio-fertilizers with any chemical products while applying and also ensure that there should be a gap of 6-8 days before or after the biofertilizer application for applying any chemicals into the field.  Integrate the use of biofertilizers alongside chemical fertilizers and organic manures. They are not substitute for fertilizers, but rather are a means to supplement the nutrient requirements of plants.