fertilizer industry latest news updates information

You are here: Home » News » Industry Trends » Fertilizer Biostimulants Explained: Functions, Growth Stage Benefits, Risks, and Raw Material Comparison

Fertilizer Biostimulants Explained: Functions, Growth Stage Benefits, Risks, and Raw Material Comparison

Views: 0 Author: Site Editor Publish Time: 2025-12-18 Origin: Site

Inquire

Fertilizer biostimulants have become an essential part of modern crop nutrition and sustainable agriculture. Unlike conventional fertilizers that primarily supply nutrients, biostimulants work by stimulating natural plant and soil processes, improving nutrient efficiency, stress tolerance, crop quality, and yield stability. This article provides a comprehensive overview of what biostimulants are, how they function at different crop growth stages, their component categories, potential risks related to misuse, and a comparison of their major raw material sources.

1. What Are Biostimulants?

According to widely accepted international definitions from the European Union (EU) and the Food and Agriculture Organization (FAO), plant biostimulants are substances or microorganisms that, when applied to plants or soils, stimulate natural physiological processes in crops. Their primary functions are to:

Improve nutrient uptake and nutrient use efficiency
Enhance tolerance to abiotic stress such as drought, salinity, and temperature extremes
Improve crop quality, yield potential, and yield stability

Biostimulants do not directly supply essential nutrients and therefore do not replace fertilizers. Instead, they enhance the effectiveness of conventional fertilization programs by optimizing plant metabolism and soil–plant interactions.

From both a practical and regulatory perspective, fertilizer biostimulants can be broadly classified into the following major component categories:

Humic substances (humic acid, fulvic acid, humin), which improve soil structure, chelate nutrients, and stimulate root activity
Seaweed and botanical extracts, rich in naturally occurring phytohormones and polysaccharides that promote growth and stress tolerance
Amino acids and protein hydrolysates, which provide readily available organic nitrogen compounds and support stress recovery
Chitosan and oligosaccharides, known for activating plant defense mechanisms and improving resistance to biotic and abiotic stress
Microbial biostimulants, including beneficial bacteria and fungi that enhance nutrient solubilization and root–soil interactions
Organic carbon–based compounds, such as organic acids and carbon extracts, which stimulate soil microbial activity and nutrient cycling

2. Role of Biostimulants at Different Crop Growth Stages

Biostimulants deliver the greatest agronomic benefits when applied at critical crop growth stages, where plant physiological demand is highest.

Crop Growth Stage	Main Physiological Role	Common Biostimulant Types	Key Agronomic Benefits
Seed Germination & Early Rooting	Stimulate cell division and root initiation	Humic acid, Fulvic acid, Amino acids, Seaweed extract	Faster germination, stronger root system, improved early vigor
Vegetative Growth	Enhance photosynthesis and nutrient assimilation	Amino acids, Protein hydrolysates, Chitosan oligosaccharides	Greener leaves, increased biomass, improved nutrient use efficiency
Flowering Stage	Improve reproductive development and pollen viability	Seaweed extract, Fulvic acid, Boron-enriched biostimulants	Uniform flowering, reduced flower drop, higher pollination success
Fruit Set	Support cell division and stress resistance	Seaweed extract, Amino acids, Microbial biostimulants	Higher fruit set rate, reduced abortion, yield stability
Fruit Enlargement & Maturation	Promote sugar accumulation and quality formation	Amino acids, Humic substances, Potassium-enhanced biostimulants	Better fruit size, coloration, firmness, improved taste
Stress & Recovery Periods (Drought, Salinity, Temperature)	Activate antioxidant systems and stress response pathways	Amino acids, Seaweed extract, Microbial biostimulants	Faster recovery, reduced yield loss, enhanced stress tolerance

3. Deficiency Symptoms Related to Biostimulant Use

Biostimulants are not essential nutrients; therefore, they do not cause classical nutrient deficiency symptoms. However, insufficient or improper use may lead to suboptimal physiological performance, including:

Weak root development
Reduced nutrient uptake efficiency
Poor stress tolerance
Lower yield stability

These symptoms typically resemble nutrient inefficiency rather than true nutrient deficiency.

4. Overuse and Misapplication Risks

Although biostimulants are generally safe, excessive or inappropriate application can result in:

Nutrient imbalance due to overstimulation
Excessive vegetative growth at the expense of reproductive development
Leaf scorch from high-concentration foliar applications
Increased production costs without proportional yield benefits

For optimal performance, biostimulants should be applied at recommended dosages and growth stages, in coordination with balanced fertilization.

5. Major Raw Material Sources of Biostimulants

Biostimulants are derived from a wide range of natural and biological raw materials, each with distinct characteristics.

Raw Material Category	Typical Sources	Main Active Components	Advantages	Limitations
Humic Substances	Leonardite, Lignite, Compost, Vermicompost	Humic acid, Fulvic acid	Improve soil structure, chelate nutrients, enhance root activity	Quality varies by source, solubility issues in low-grade materials
Seaweed Extracts	Ascophyllum nodosum, Ecklonia maxima, Sargassum spp.	Natural hormones, polysaccharides, trace elements	Strong stress resistance, improved flowering and fruiting	Higher cost, seasonal raw material supply
Amino Acids & Protein Hydrolysates	Animal proteins, Plant enzymatic hydrolysis	Free amino acids, peptides	Fast absorption, effective stress mitigation	Overuse may promote excessive vegetative growth
Chitosan & Oligosaccharides	Shrimp and crab shells, Fungal cell walls	Chitosan, chitosan oligosaccharides	Induce plant defense, improve disease resistance	Limited nutritional value, timing-sensitive application
Microbial Biostimulants	Bacillus, Azotobacter, Mycorrhizal fungi	Beneficial microorganisms	Long-term soil health, improved nutrient availability	Sensitive to storage and environmental conditions
Organic Carbon Sources	Molasses, Organic matter extracts	Organic carbon compounds	Stimulate soil microbiology, improve nutrient efficiency	Indirect plant effects, slower response

Ornamentals and Specialty Crops Vegetables High-Efficiency Protein Solution Fertilizer For Rooting And Swelling Fruits Applications4

6. Advantages and Limitations of Biostimulants

Advantages

Improve fertilizer efficiency and nutrient utilization
Enhance crop resilience to abiotic stress
Support sustainable and environmentally friendly farming practices
Improve yield quality and stability

Limitations

Cannot replace conventional fertilizers
Effectiveness depends on formulation, timing, and environmental conditions
Regulatory definitions and labeling requirements vary by country

Conclusion

Fertilizer biostimulants represent a powerful complementary tool in modern crop nutrition. By enhancing plant physiological processes rather than directly supplying nutrients, they improve fertilizer efficiency, stress tolerance, and crop performance across different growth stages. When integrated correctly with sound agronomic practices and balanced fertilization, biostimulants can significantly contribute to higher productivity and sustainable agricultural systems worldwide.