Bio-efficacy of PNP Coated Urea on Paddy.
Conducted with the Department of Soil Science & Agricultural Chemistry, TNAU Coimbatore and Agricultural Research Station, Bhavanisagar — July 2024 to Feb 2025.
"Nearly two-thirds of applied nitrogen is not used by our crops."
Trial protocol
Treatments
| Treatment | Description |
|---|---|
| T₁ | Check 100% RDF ha⁻¹ as per CPG |
| T₂ | 25% RDF of N through Urea coated with PNP ha⁻¹ |
| T₃ | 50% RDF of N through Urea coated with PNP ha⁻¹ |
| T₄ | 75% RDF of N through Urea coated with PNP ha⁻¹ |
| T₅ | 100% RDF of N through Urea coated with PNP ha⁻¹ |
| T₆ | 50% RDF of N through Urea ha⁻¹ |
| T₇ | 75% RDF of N through Urea ha⁻¹ |
| T₈ | INM 75% RDF of N through Urea + Biofertilizers 6 kg ha⁻¹ |
Common to T₁–T₈: 50 kg P₂O₅ + 50 kg K₂O ha⁻¹ + 25 kg ZnSO₄ ha⁻¹. Biofertilizers: 2 kg each of Azospirillum, Phospho-bacteria, Potash bacteria. RDF = Recommended Dose of Fertilizer.
Trial documentation at TNAU
Stage-by-stage photography of the UREGOLD bio-efficacy trial on paddy. Tap any photo to enlarge with full trial metadata.
What we measured
Release behavior of UREGOLD
- • Moderately affected by temperature
- • Not significantly affected by soil moisture levels
- • Unaffected by soil type or soil pH
- • PNP coat with microscopic ~0.1 μm holes — gradual diffusion of nutrients
Bio-efficacy of PNP Coated Urea on Maize / Corn
A parallel field study on maize/corn evaluates the same UREGOLD PNP coated urea formulations across graded N rates — measuring vigor, cob development and grain yield versus conventional urea and INM checks.
From the maize field
UREGOLD field study & science — FAQ
Common questions about the TNAU and Bhavanisagar bio-efficacy trials and what the data shows about PNP coated urea.
Related research and agronomy guides.
Nitrogen use efficiency (NUE) measures how much of the nitrogen you apply actually ends up in your crop. Here is how to lift it — without sacrificing yield.
A practical introduction to PNP coated urea — what the coating does, why it improves nitrogen efficiency, and how it differs from conventional urea and neem-coated urea.
What Potassium Nitrophenolates actually are, how 2-PNP, 4-PNP and 5-PNP differ, and why this trio is the active backbone of modern bio-stimulant fertilizers.