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How to make Urea more efficient as a fertiliser, and why that’s needed

Fortification of urea, DAP and other commodity fertilisers with micronutrients is the way forward for boosting crop yields and maximising the use efficiency of imported nutrients .

Making urea deliver moreA worker sprays fertilisers on a field in Punjab. (Express File Photo/Gurmeet Singh)
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How to make Urea more efficient as a fertiliser, and why that’s needed
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Late last month, Prime Minister Narendra Modi officially launched ‘Urea Gold’ fertiliser. Developed by the state-owned Rashtriya Chemicals and Fertilizers Ltd (RCF), it is basically urea fortified with sulphur.

Normal urea contains 46% of a single plant nutrient: Nitrogen or N. Urea Gold has 37% N plus 17% sulphur or S and aims at two things. The first is to deliver S along with N. Indian soils are deficient in S, which oilseeds and pulses – the country is significantly import-dependent in both – particularly require.

The second is to improve the nitrogen use efficiency (NUE) of urea. Coating of S over urea ensures a more gradual release of N. By prolonging the urea action, the plants stay greener for a longer time. Farmers tend to apply urea when they notice the leaves turning yellowish. If the crop retains greenness for an extended period, they would reduce the frequency of application and use, say, only two bags, as against three, for an acre of paddy or wheat.

RCF is yet to commercially introduce Urea Gold or reveal any pricing details. The maximum retail price (MRP) for a 45-kg bag of ordinary neem-coated urea is around Rs 254, net of local taxes. Indications are that Urea Gold, given its higher NUE from the slow-release mechanism, may be sold in 40-kg bags. The MRP is expected to be fixed at Rs 400-500 per 40-kg bag.

The problem

Urea is India’s most widely used fertiliser, with its consumption/sales rising from 26.7 million tonnes (mt) to 35.7 mt between 2009-10 and 2022-23. The Modi government’s measures, such as mandatory coating of all urea with neem oil and reducing the size of bags from 50 to 45 kg, enabled a slight dip after 2013-14 till 2017-18. But the subsequent period has shown renewed uptrend.

Making urea deliver more Source: Fertiliser Association of India


There are two concerns over rising urea consumption. The first is imports, which accounted for 7.6 mt out of the total 35.7 mt sold last fiscal. Even with regard to domestically-manufactured urea, the feedstock used – natural gas – is mostly imported. India’s nearly 36-mt annual consumption of urea is today next only to China’s 51 mt, with the latter’s production largely coal-based.


The second concern is NUE. Barely 35% of the N applied through urea in India is actually utilised by crops to produce harvested yields. The balance 65% N is unavailable to the plants, much of it “lost” through release into the atmosphere as ammonia gas or leaching below the ground after conversion into nitrate. Declining NUE, from an estimated 48% in the early 1960s, has resulted in farmers applying more and more fertiliser for the same yield.

Making urea deliver more Source: Bijay Singh, Agricultural Research, August 2022.

The fortification solution

There is growing consensus, including in the government, that India cannot sustain the above increase in consumption of urea – or even di-ammonium phosphate (DAP), muriate of potash and other fertilisers containing just primary nutrients: N, P (phosphorus) and K (potassium).


A country with hardly any natural gas or rock phosphate, potash and sulphur reserves shouldn’t, beyond a point, encourage the consumption of these commodity fertilisers in plain-vanilla form.  Instead, they must be coated with secondary nutrients (S, calcium and magnesium) as well as micronutrients (zinc, boron, manganese, molybdenum, iron, copper and nickel).

Coating not only allows urea or DAP to be used as “carrier products” for delivering secondary and micro nutrients to crops. It improves their own N and P use efficiency through synergetic effects and controlled release that, in the case of urea, helps reduce losses through ammonia volatilisation and nitrate leaching.

Yara International, a $24.1 billion-revenue Norwegian crop nutrition company, has a proprietary ‘Procote’ technology for coating all commodity fertilisers with any micronutrient. Its Indian subsidiary – which has a 1.2-mt urea plant at Babrala in Uttar Pradesh’s Sambhal district – launched ‘Procote Zn’ for coating of urea with zinc oxide during the 2022 kharif season.

“Punjab and Haryana farmers growing paddy usually mix 5 kg of zinc sulphate (having 33% Zn content) with a 45-kg bag of urea per acre 10-12 days after transplanting. Here, they need apply just 325-350 ml of Procote Zn (containing 39.5% Zn), again by mixing with 45 kg of urea,” said Sanjiv Kanwar, managing director, Yara Fertilisers India Pvt. Ltd.

Being a powder, zinc sulphate is prone to losses during mixing and application. The micronutrient particles also don’t get uniformly distributed over all the urea prills that are of 1-2 mm diameter. Procote Zn, by contrast, is a palm oil-based suspension concentrate that farmers can simply pour, mix and rub in their urea before application.


“There’s no dust loss and every single urea prill will now carry a thin lining of Zn, even with only 325-350 ml and not 5 kg of coating material,” claimed Kanwar. Yara is planning next to commercialise ‘Procote B’ (boron) and ‘Procote BMZ’ (boron, manganese and zinc) in India – based on the same dust-free micronutrient coating technology platform – for which field trials are underway.

The hurdle

That has to do with pricing.

The government currently permits coating of urea with zinc (for which fertiliser concerns can recover an extra Rs 542 per tonne or about Rs 24 for a 45-kg bag) and sulphur (for which the MRP is still to be finalized). Urea apart, an additional subsidy of Rs 300 and Rs 500 per tonne is being provided for P&K fertilisers fortified with boron and zinc, respectively.


These additional rates aren’t attractive enough for companies to market zincated urea, boronated DAP or any of the 20-odd fortified products recognised under the Fertiliser Control Order.

This is despite the proven benefits of micronutrient fortification: Yara’s field trials have demonstrated average paddy yields for the ‘PR-126’ variety in Punjab increasing from 24-25 to 26-27 quintals per acre, when farmers apply zinc sulphate on top of urea. It goes up further to 30 quintals with Procote Zn. Sulphur-coated urea has been similarly found by the Indian Agricultural Research Institute to boost wheat yields by roughly 10% and enhance nitrogen efficiency by 60%.


For now, there’s not much incentive for fortification. Yara is selling urea and Procote Zn separately. Farmers are paying the controlled MRP of Rs 254 for a 45-kg bag of urea and Rs 530-550 for 325-350 ml of Procote Zn. The latter price is marginally higher than the Rs 500 that 5 kg of zinc sulphate is costing them.

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“Ideally, the coating should be carried out at the factory itself, which will guarantee even more uniform distribution of micronutrients and save the farmer the hassles of mixing. The government can probably set free the MRPs for all coated fertilisers. Since the regular urea or DAP will continue to be sold at heavily subsidised rates, companies cannot charge too much of premium on their fortified fertiliser products,” Kanwar pointed out.

First published on: 14-08-2023 at 05:05 IST
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