Nano-Fertilizers

• Introduction: Nano-fertilizers are a new generation of fertilizers developed using nanotechnology, where nutrients are supplied in nanoscale particles (1–100 nm).
  They are designed to improve nutrient use efficiency (NUE), reduce fertilizer losses, and minimize environmental pollution, making them important for precision and sustainable agriculture.
• Definition; Nano-fertilizers are fertilizers that contain nutrients in nanosized particles or nutrients encapsulated/coated with nanomaterials, enabling controlled release and enhanced uptake by plants.

Characteristics of Nano-Fertilizers

• Nanoscale size (1–100 nm): Extremely small particle size increases contact with plant surfaces and root zones.
• High surface area & reactivity: Enhances nutrient interaction with plant cells and improves absorption efficiency.
• Controlled nutrient release: Nutrients are released slowly and steadily, matching crop demand.
• High nutrient use efficiency (NUE): Minimizes nutrient losses and maximizes plant uptake.
• Effective at low doses: Very small quantities are sufficient due to high efficiency.
• Suitable for foliar & soil application: Easily absorbed through leaves and roots.
• Reduced nutrient losses: Lower leaching (N, K), volatilization (N), and fixation (P, micronutrients).

Types of Nano-Fertilizers 

i) Nano-Nitrogen Fertilizers

• Nitrogen is encapsulated or coated in nanomaterials.
• Supply nitrogen in a slow and sustained manner.
• Reduce nitrogen losses due to leaching and volatilization.
• Improve nitrogen use efficiency.
• Example: Nano-Urea (IFFCO)

ii) Nano-Phosphorus Fertilizers

• Increase phosphorus solubility in soil.
• Reduce phosphorus fixation by Fe, Al, and Ca.
• Improve phosphorus availability in acidic and calcareous soils.
• Promote better root growth and early crop establishment.

iii) Nano-Potassium Fertilizers

• Enhance potassium uptake efficiency.
• Improve plant water balance, enzyme activity, and stress tolerance.
• Increase crop quality such as grain filling and fruit size.

iv) Nano-Micronutrient Fertilizers

• Include Nano-Zn, Nano-Fe, Nano-Cu, Nano-Mn.
• Correct micronutrient deficiencies at very low doses.
• Highly effective through foliar application.
• Reduce fixation and increase nutrient availability.

Mode of Action of Nano-Fertilizers

• Nano-particles enter plants through:
  • Leaf stomata
  • Cuticular pores
  • Root pores
• Nutrients are released gradually and in controlled manner.
• High surface area enables better contact with plant cells.
• Improves nutrient absorption at cellular and molecular level.
• Enhances metabolic efficiency, photosynthesis, and growth response.

Advantages of Nano-Fertilizers

• Increase nutrient use efficiency (NUE).
• Reduce overall fertilizer requirement.
• Minimize environmental pollution.
• Reduce nutrient losses due to leaching, volatilization, and fixation.
• Improve crop yield and quality.
• Support precision farming and site-specific nutrient management.
• Suitable for climate-smart and sustainable agriculture.

Limitations of Nano-Fertilizers

• High production and formulation cost.
• Limited long-term field validation.
• Need for standardization, regulation, and guidelines.
• Require technical knowledge for proper use.
• Possible environmental and health concerns if misused.

Important Points

1. Nano-fertilizers contain nutrients in nanoscale (1–100 nm) or nutrients encapsulated/coated with nanomaterials for controlled release.
2. They are designed to increase nutrient use efficiency (NUE) and reduce fertilizer losses.
3. Due to very high surface area and reactivity, nano-fertilizers show better interaction with plant cells.
4. Nano-Urea (IFFCO) is the first widely commercialized nano-nitrogen fertilizer in India.
5. Nano-fertilizers are effective at very low doses compared to conventional fertilizers.
6. Nutrients enter plants through leaf stomata, cuticle, and root pores.
7. Nano-fertilizers provide slow and controlled nutrient release, matching crop demand.
8. They reduce nutrient losses such as leaching (N, K), volatilization (N), and fixation (P, micronutrients).
9. Nano-micronutrient fertilizers (Nano-Zn, Nano-Fe, etc.) are highly effective in foliar application.
10. Nano-fertilizers support precision farming, climate-smart agriculture, and sustainable nutrient management.