Beijerinckia indica
As a versatile free-living diazotroph, Beijerinckia indica can sustainably supplement up to 40% of nitrogen fertilizer requirements, improve soil health, and enhance crop resilience across diverse…
Strength
1 x 10⁸ CFU per gram / 1 x 10⁹ CFU per gram
Benefits
Plant Growth Promotion
It produces growth-promoting substances like phytohormones and siderophores, which stimulate plant growth, nutrient uptake, and overall health.
Heavy Metal Remediation
Beijerinckia indica has the ability to detoxify heavy metals in contaminated soils, reducing their toxicity and improving soil health for plant growth.
Drought Tolerance
It produces exopolysaccharides that help improve soil structure and water-holding capacity, thus promoting drought tolerance in plants.
Nitrogen Fixation
Beijerinckia indica fixes atmospheric nitrogen into ammonia, contributing to soil fertility and enhancing plant growth without the need for nitrogen fertilizers.
Scientific References
Case Studies and Trials
Ultisol Sugarcane, India: Biomass N uptake matched 120 kg N/ha synthetic regimen; soil N increased by 15 kg N/ha post-harvest.scielo
Greenhouse Pepper, Brazil: Combined inoculation in manure improved extractable P by 18% and K by 12% due to accelerated mineralization.oiccpress
Field Lettuce, Indonesia: Single application improved marketable yield by 20% and enhanced shelf life via higher soluble solids.
Integration into Crop Management
Incorporate B. indica early in season; adjust chemical N inputs based on soil testing, maintaining minimum 60% of standard rate when inoculated. Rotate biofertilizer application annually to sustain microbial diversity.
Future Prospects and Innovations
Genetic Engineering: Efforts to overexpress nif genes aim to boost fixation efficiency under full-aerobic conditions.
Nanocarriers: Encapsulation in nano-biopolymers for controlled release and improved shelf stability.
Consortia Development: Blends with mycorrhizal fungi and phosphate-solubilizing bacteria for multi-nutrient biofertilizers.
Mode of Action
Atmospheric N₂ Fixation: Expresses nitrogenase complex (nifHDK genes), reducing atmospheric N₂ to NH₄⁺ in the rhizosphere, elevating soil nitrogen pools.
Phytohormone Production: Synthesizes indole-3-acetic acid (IAA) at 10–20 µg/mL, stimulating lateral root initiation and root hair elongation for improved nutrient uptake.oiccpress
Siderophore Secretion: Releases catechol and hydroxamate siderophores, chelating Fe³⁺ and enhancing iron availability under limiting conditions.
Synergistic Interactions: Co-inoculation with fungi (e.g., Cunninghamella elegans) accelerates organic waste mineralization, boosting macronutrient release and soil organic matter turnover.oiccpress
Additional Info
Taxonomy and Characteristics
Beijerinckia indica belongs to the family Beijerinckiaceae within the class Alphaproteobacteria. It presents as Gram-negative, rod-shaped cells (0.8–1.2 µm × 2–5 µm), motile via single polar flagella, and forms mucoid colonies on nitrogen-free media.
Physiology and Environmental Adaptations
Nitrogenase Activity: Operates optimally under micro-aerobic (<10% O₂) conditions, fixing 20–30 kg N/ha per cropping cycle by converting N₂ to NH₄⁺.jurnal.unipar+1
pH Tolerance: Maintains activity from pH 3.0 to 8.0, with acid-stable nitrogenase variants performing down to pH 3.0 in acidic soils.pmc.ncbi.nlm.nih
Carbon Utilization: Utilizes C₁ compounds (e.g., methanol) and simple sugars, supporting survival in varied organic amendments.
Stress Resistance: Produces compatible solutes (e.g., proline) and antioxidative enzymes, enhancing drought and salinity tolerance in host plants.
Formulations and Application Guidelines
Formulations
Carrier: Sterile talc or peat (CFU ≥ 1×10⁸/g); liquid formulations with protectants maintain viability at 1×10⁹ CFU/mL.
Co-formulations: Compatible with other biofertilizers (e.g., Azospirillum, Rhizobium); avoid broad-spectrum fungicides.
Dosage and Methods
Application Method | Rate | Timing |
Seed Treatment | 10 g inoculum + 10 g sugar per 1 kg seed | Pre-sowing (slurry coat) |
Seedling Dip | 100 g inoculum per 10 L water | At transplanting |
Soil Incorporation | 3–5 kg inoculum per acre mixed with organic manure | At planting or pre-sowing |
Irrigation Drench | 3 kg inoculum per acre in irrigation water | Veg. stage or flowering onset |
Storage and Shelf Life
Store at 4–10 °C in airtight packs; shelf life up to 12 months with CFU retention ≥ 1×10⁸/g. Protect from UV exposure and moisture.
Recommended Crops
Cereals, Millets, Pulses, Oilseeds, Fibre Crops, Sugar Crops, Forage Crops, Plantation crops, Vegetables, Fruits, Spices, Flowers, Medicinal crops, Aromatic Crops, Orchards, and Ornamentals.
Dosage & Application
Seed Coating/Seed Treatment: Coat 1 kg of seeds with a slurry mixture of 10 g of Beijerinckia Indica and 10 g of crude sugar in sufficient water. Dry the coated seeds in shade before sowing or broadcasting in the field.
Seedling Treatment: Dip seedlings into a mixture of 100 grams of Beijerinckia Indica with sufficient water.
Soil Treatment: Mix 3-5 kg per acre of Beijerinckia Indica with organic manure or fertilizers. Incorporate into the soil during planting or sowing.
Irrigation: Mix 3 kg per acre of Beijerinckia Indica in water and apply through drip lines.
FAQ
Which crops see greatest response?
Legumes, cereals, sugarcane, vegetables, and ornamentals all show 10–25% yield gains under inoculation.
How soon after application are effects measurable? R
oot development benefits appear within 2–3 weeks; yield impacts by reproductive stage.
Is co-application with chemical fertilizers possible?
Yes—apply B. indica separately, then follow with reduced-rate NPK; avoid simultaneous mixing with acidifiers or oxidizers.
What regulatory approvals exist?
Approved under national biofertilizer standards in India, Brazil, and Indonesia; registration procured following OECD guidelines for microbial inoculants.
