Bacillus velezensis is a beneficial soil bacterium that can significantly enhance plant growth, health, and resilience through multiple mechanisms. Below is a concise overview of how plants can benefit from Bacillus velezensis:
Plant Growth Promotion:
Bacillus velezensis produces phytohormones like indole-3-acetic acid (IAA), gibberellins, and cytokinins, which stimulate root and shoot growth, leading to improved nutrient uptake and overall plant vigor.
It enhances nutrient availability by solubilizing minerals such as phosphorus and potassium, making them more accessible to plants.
Biocontrol of Pathogens:
The bacterium produces antimicrobial compounds, including lipopeptides (e.g., surfactin, iturin, and fengycin), which suppress soil-borne pathogens like Fusarium, Rhizoctonia, and Phytophthora.
It induces systemic resistance (ISR) in plants, boosting their natural defense mechanisms against fungal, bacterial, and viral diseases.
Stress Tolerance:
Bacillus velezensis helps plants cope with abiotic stresses like drought, salinity, and heavy metal toxicity by producing stress-mitigating compounds and enzymes, such as ACC deaminase, which reduces ethylene levels under stress.
It forms biofilms around roots, protecting them from environmental stressors and improving water retention.
Soil Health Improvement:
The bacterium enhances soil microbial diversity and activity, contributing to better soil structure and fertility.
It degrades organic matter, releasing nutrients that plants can use, thus improving soil quality over time.
Bioremediation:
Bacillus velezensis can detoxify heavy metals and pollutants in the soil, creating a healthier environment for plant growth.
Applications:
Used as a biofertilizer or biopesticide in agriculture to reduce reliance on chemical inputs.
Applied via seed coating, soil drenching, or foliar spraying to maximize benefits.
Examples:
Studies have shown Bacillus velezensis improving yields in crops like wheat, rice, and tomatoes by enhancing growth and protecting against diseases like root rot or blight.
It’s particularly effective in sustainable farming systems, promoting eco-friendly practices.