Nano urea was sold on a substitution claim: replace half your conventional urea with a 500 ml bottle. In March 2026 the government cut the permitted nano dose from 50 per cent to 25. The independent trial that prompted it found 50 per cent substitution cut rice yield 13 per cent and wheat 17.2 per cent. The interesting part is that IFFCO’s own funded research says roughly the same thing.
Nano Urea Works as a Supplement and Fails as a Substitute. The Rulebook Now Agrees.
The short version.
- IFFCO’s 2021 protocol: 50 per cent conventional urea as basal dose, 50 per cent replaced by nano urea foliar spray. Claimed nutrient use efficiency of 85–90 per cent against 25 per cent for conventional.
- A Punjab Agricultural University trial found that protocol cut rice yield 13 per cent and wheat 17.2 per cent, with grain protein down 35 and 24 per cent.
- A 2026 study funded by IFFCO found 50 per cent nitrogen reduction caused 16–19 per cent yield penalties — while 25–34 per cent reduction plus two sprays held yield.
- On 9 March 2026 the Fertiliser Control Order was amended to cut the nano dose to 25 per cent. On 13 March a second amendment banned selling it by tagging it to other fertilisers.
- Nano urea is a real product with a real effect. The effect is additive, at a low replacement rate. It was marketed as a replacement at double that rate.
The claim that was made
India’s urea problem is well documented on this blog: a heavily subsidised nutrient, applied far past the agronomic optimum, with a nitrogen-to-phosphate-to-potash ratio that has drifted from the recommended 4:2:1 in most states. Anything that credibly reduced urea use would be valuable, and in 2021 the Indian Farmers Fertiliser Cooperative said it had one.
The protocol was specific and easy to communicate. Apply half the recommended dose of conventional urea at sowing. Replace the other half with foliar sprays of nano urea from a 500 ml bottle. The supporting claim was that nano urea achieves 85 to 90 per cent nutrient use efficiency against roughly 25 per cent for granular urea — a plausible-sounding number, since most granular nitrogen genuinely is lost to volatilisation and leaching.
The evidence offered was volume. IFFCO reported testing on over 11,000 farm fields across 94 crops, and trials at more than 20 agricultural research institutes covering 43 crops. That is a lot of testing, and it is worth noting it as a genuine effort rather than dismissing it.
What the independent trial found
In December 2024 Punjab Agricultural University published results on exactly the protocol as marketed — two nano urea sprays substituting for 50 per cent of the recommended nitrogen dose.
| Outcome under 50% nano substitution | Rice | Wheat |
|---|---|---|
| Change in grain yield | −13% | −17.2% |
| Change in grain protein content | −35% | −24% |
Punjab Agricultural University, December 2024, against 100 per cent recommended dose of nitrogen applied to soil.
The protein result is the one that deserves attention and got least. A yield loss is a farm-income problem. A 35 per cent fall in grain protein is a nutrition problem, and it would not show up in any metric a fertiliser programme tracks. The trial lead’s summary was unadorned: if the plant’s needs are not met by 50 per cent nano sprays, both yield and quality fall.
And what IFFCO’s own funded study found
This is where the story stops being a dispute between a manufacturer and a critic.
In April 2026 Frontiers in Sustainable Food Systems published a three-season rice trial run at Varanasi and Guwahati, testing nitrogen at 100, 75, 66, 50 and 33 per cent of the recommended dose against zero to three nano-urea sprays, in a randomised block design with three replications. The funder, stated in the paper, is the Indian Farmers Fertiliser Cooperative.
| Nitrogen level | With nano-urea sprays | Outcome vs 100% recommended dose |
|---|---|---|
| 75% and 66% of RDN | Two foliar applications | Yields comparable; economic returns comparable |
| 50% of RDN | Sprays applied | 16–19% yield penalty (0.88–1.2 t/ha lost) |
Frontiers in Sustainable Food Systems, 29 April 2026; two locations, three kharif seasons 2022–2024; nano-urea at 4% N in 2022-23 and 20% N in 2024. Funded by IFFCO; authors declared no conflict of interest. Nitrogen savings recorded at 27–40 kg/ha in Varanasi and 15–20 kg/ha in Guwahati.
Read the two together and the picture is coherent rather than contradictory. Nano urea does something. At a nitrogen reduction of a quarter to a third, two foliar sprays hold yield and save 15 to 40 kg of nitrogen per hectare, which is a genuinely useful result. Push the substitution to half and the yield falls away in both datasets — 13 to 17.2 per cent in Punjab, 16 to 19 per cent in the IFFCO-funded work.
The product was not fraudulent. The dose was wrong, and the dose was the part that was marketed.
The rulebook caught up in March 2026
Policy moved in three steps, and the sequence is legible.
| Date | Action | Effect |
|---|---|---|
| July 2025 | Agriculture Minister writes to chief ministers | Requests legal action against coercive nano-fertiliser sales |
| 13 February 2026 | Ministry mandates fresh bio-efficacy trials | Multiple ICAR institutions, 12 major crops, across agro-climatic zones — efficacy, productivity, nitrogen use efficiency, long-term soil impact, bio-safety |
| 9 March 2026 | Fertiliser Control Order amended | Nano dose cut from 50% to 25% of nutrient requirement; new protocol is 75% RDF plus 25% nano |
| 13 March 2026 | Fertiliser Control Order amended again | No forced sale of nano fertilisers by tagging them to other fertilisers or agri-inputs |
The 9 March amendment is the substantive one. It halves the permitted substitution rate, and in doing so it moves the official protocol from the level both trial datasets say fails to the level both say works. That is regulation following evidence, which is worth acknowledging plainly.
The 13 March amendment is the more revealing one. A rule prohibiting the sale of a product by tagging it to another product exists only because that was happening. Nano urea was being moved by bundling it with conventional fertiliser that farmers actually wanted — which is a distribution fact, not an agronomy fact, and it tells you the product was not being pulled through by demand.
Why this matters beyond one product
India’s fertiliser problem is a subsidy problem wearing an agronomy costume. Urea is cheap because it is subsidised; it is over-applied because it is cheap; the nutrient ratio skews because the subsidy is nutrient-specific. Every proposed fix has to survive contact with that structure.
Nano urea was attractive precisely because it promised to solve the problem without touching the subsidy. If a 500 ml bottle could replace half a 45 kg bag, urea consumption would fall without anyone having to raise the price of urea or change the subsidy design. The appeal was fiscal and political as much as agronomic.
At a 25 per cent substitution rate the product still helps — 15 to 40 kg of nitrogen per hectare is not nothing across a country that applies tens of millions of tonnes. But it is an incremental efficiency gain, not a structural fix, and it does not remove the need to deal with the subsidy itself. The Economic Survey’s direct benefit transfer recommendation, discussed in an earlier piece here, addresses the structure. A foliar spray does not.
What to watch
- The February 2026 ICAR bio-efficacy trials. Twelve crops across agro-climatic zones, examining long-term soil impact and bio-safety as well as yield. This is the first evaluation designed by the regulator rather than the manufacturer, and its results will settle most of what is still contested.
- Whether 25 per cent survives. The dose has already moved once. If the ICAR trials find the effect is smaller still outside the two-location rice systems tested so far, it moves again.
- Sales volumes after the tagging ban. If nano urea was moving because it was bundled, the 13 March amendment should show up as a volume fall. That is a clean natural experiment on whether there was ever real demand.
- Grain protein, not just yield. The 35 per cent protein drop in the Punjab rice trial is the least-tracked result in this whole episode, and nothing in the announced trial framework obviously captures nutritional quality.
The honest summary
Nano urea is not a hoax, and the people who tested it at 11,000 sites were not inventing data. What happened is more ordinary and more instructive: a product with a modest, real benefit at a low replacement rate was marketed at double that rate, because the higher number was what made the business case and the policy case work.
The correction arrived from three directions at once and they agree. An independent university trial, a study funded by the manufacturer, and an amendment to the Fertiliser Control Order all now put the workable substitution rate at or below a quarter. The government has written that number into the rules. The remaining question is not whether nano urea works — at 25 per cent it appears to — but whether an incremental efficiency gain was ever going to substitute for fixing the subsidy that causes the over-application in the first place.
What would fix this
- ICAR should add grain protein content as a reported outcome in the bio-efficacy trials ordered in February 2026, and publish crop-wise results with the underlying data, so the 35% protein fall seen in the Punjab rice trial is measured by the regulator’s own evaluation and not only by yield.
- The Department of Fertilizers should publish monthly nano urea sales by state for the twelve months either side of the 13 March 2026 tagging ban, so the natural experiment on whether demand was real can be read from official data.
- The Ministry of Agriculture should require any nano fertiliser seeking Fertiliser Control Order notification to submit independent multi-location trials at the exact substitution rate it will be marketed at, so a dose is not corrected five years after launch, as the 50% protocol was.
- IFFCO should withdraw promotional and packaging material stating the 50% replacement protocol or the 85–90% nutrient-use-efficiency claim, and publish the date by which this is done, so farmers see the same 75% RDF plus 25% nano protocol the March 2026 amendment now sets.
- State agriculture departments should publish the number of complaints received and actions taken under the 13 March 2026 Fertiliser Control Order amendment against tagged sales, so enforcement of the ban on forced bundling can be checked state by state.
These are proposals from this blog, not recommendations any agency has adopted.
Sources and caveats
Update sources, 7 November 2026: Uttam Gupta, “Why has nano-urea failed to secure a foothold on India’s fertilizer landscape?” (29 July 2026), citing Department of Fertilizers data (search-result summary); DD News, cumulative nano-fertiliser sales of 1,593.37 lakh bottles, including 1,219.27 lakh of nano urea; The Policy Edge, summary of Lok Sabha Unstarred Question 3326 (7 August 2026); Rajya Sabha Unstarred Question 255 (20 July 2026), on the National Productivity Council studies.
The IFFCO protocol as launched in 2021 — 50 per cent conventional urea as basal dose, 50 per cent replaced by nano urea foliar spray from 500 ml bottles, with a claimed nutrient use efficiency of 85 to 90 per cent against about 25 per cent for conventional urea — and IFFCO’s testing claims of over 11,000 farm fields across 94 crops plus trials at more than 20 research institutes covering 43 crops, are as reported by Business Today (14 April 2026). The Punjab Agricultural University results — rice grain yield down 13 per cent, wheat down 17.2 per cent, grain protein down 35 per cent in rice and 24 per cent in wheat under two nano-urea sprays substituting 50 per cent of the recommended nitrogen dose, published December 2024, with the quoted summary from study lead Rajeev Sikka — are from the same Business Today report; the underlying paper was not retrieved directly for this piece. The multi-season rice trial is Frontiers in Sustainable Food Systems, published 29 April 2026: two locations (Varanasi and Guwahati), three kharif seasons 2022 to 2024, randomised block design with three replications, nitrogen at 100, 75, 66, 50 and 33 per cent of the recommended dose against zero to three nano-urea sprays, nano-urea at 4 per cent N in 2022-23 and 20 per cent N in 2024. Its findings that 66 to 75 per cent of RDN with two foliar applications produced yields and economic returns comparable to full dose, that 50 per cent caused 16 to 19 per cent yield penalties of 0.88 to 1.2 t/ha, and nitrogen savings of 27 to 40 kg/ha at Varanasi and 15 to 20 kg/ha at Guwahati, are from the paper. The paper states it was funded by the Indian Farmers Fertiliser Cooperative Limited; the authors declared no conflict of interest. That funding relationship is disclosed here because it strengthens rather than weakens the argument — a manufacturer-funded study finding against the manufacturer’s own marketed dose is unusually strong evidence. The Fertiliser Control Order amendments of 9 March 2026 (nano dose cut from 50 to 25 per cent, new protocol 75 per cent RDF with 25 per cent nano) and 13 March 2026 (prohibition on forced sale by tagging), the Agriculture Minister’s July 2025 letter to chief ministers, and the 13 February 2026 mandate for ICAR bio-efficacy trials across 12 major crops, are as reported by Business Today; the gazette notifications themselves were not retrieved for this piece and readers relying on the exact legal text should consult them directly. Both trial datasets discussed here are rice-and-wheat systems in northern and eastern India. Nano urea’s performance on other crops and in other agro-climatic zones is precisely what the February 2026 trial framework is designed to establish, and is not settled by anything cited above. Nothing in this piece is agronomic, investment or policy advice, and no reader should change a fertiliser regime on the basis of it.
About this article: Researched, written and edited by Umashankar Triplicane Dwarakanathan, with AI research assistance; every figure is meant to trace to the primary source cited. See the Editorial Policy for how sourcing, AI use and corrections work.
