New Delhi, July 21 -- The Union agriculture ministry has called for stricter checks on crop nutrients such as nano urea and a possible ban on growth boosters known as biostimulants after complaints from farmers that these have increased costs without clear results, a move that follows an initial policy to push a set of newer forms of fertilisers. Agriculture minister Shivraj Singh Chouhan has ordered a crackdown on unregulated biostimulants, said to have no proven benefits on crop health, besides writing to states to prohibit the forced selling of nano urea, a newer, liquid form of the fertiliser popularised by the Modi government as a more efficient alternative since being launched in 2021. To be sure, the government has not changed its po...