Scientists are unsure about how ‘Nano Urea’ benefits crops

Farmers are benefitting from it and, ultimately, they are the best judge, says inventor Ramesh Raliya

‘Nano Urea’, a fertilizer patented and sold by the Indian Farmers Fertiliser Cooperative Limited (IFFCO), has been approved by the government for commercial use because of its potential to substantially reduce the import bill, but several experts have questioned the science underlying its efficacy.

Prime Minister Narendra Modi, while inaugurating a Nano Urea production plant at Kalol, Gujarat on May 28, said, “…a small bottle (500 ml) of Nano Urea is equivalent to one 50 kg bag of granular urea currently used by farmers”.

IFFCO’s Nano Urea contains nitrogen, an element critical for plant development, in the form of granules that are a hundred thousand times finer than a sheet of paper. At this ‘nano’ scale, which is about a billionth of a metre, materials behave differently than in the visible realm.

Ramesh Raliya, 34, who is credited as the inventor of Nano Urea and is now a consultant with IFFCO, told The Hindu that his process uses “organic polymers” that keeps the ‘nano’ particles of nitrogen stable and in a form that can be sprayed onto plants.

Chemically, packaged urea is 46% nitrogen, which means a 45 kg sack contains about 20 kg of nitrogen. Contrastingly, Nano Urea sold in 500 ml bottles has only 4% nitrogen (or around 20 gm). How this can compensate for the kilogrammes of nitrogen normally required puzzles scientists.

Plants need nitrogen to make protein and they source almost all of it from soil bacteria which live in a plant’s roots and have the ability to break down atmospheric nitrogen, or that from chemicals such as urea, into a form usable by plants.

To produce one tonne of wheat grain, a plant needs 25 kg of nitrogen. For rice, it’s 20 kg of nitrogen, and for maize, it’s 30 kg of nitrogen. Not all the urea cast on the soil, or sprayed on leaves in the case of Nano Urea, can be utilised by the plant. If 60% of the available nitrogen were used, it would yield 496 kg of wheat grain. Even if 100% of 20 gm of Nano Urea, which is what is effectively available, is utilised by the plant, it will yield only 368 gm of grain, said N.K. Tomar, retired Professor of Soil Science at Chaudhary Charan Singh Haryana Agriculture University, Hissar, Haryana.