Punjab requires roughly 5.50 lakh tonnes of di-ammonium phosphate (DAP) annually, the bulk of which — around 4.8 lakh tonnes — is needed during the Rabi (October-March) season to cultivate wheat, potatoes, and other horticulture crops. But the supply of the conventionally used granular DAP, the majority of which is imported, has been unreliable, with shortfalls and delays triggering panic among farmers. This is why agro-scientists and policymakers have long been exploring alternatives, such as Indian Farmers Fertiliser Cooperative Ltd-developed nano DAP. Can this replace the conventional granular DAP in Punjab? First, how is nano DAP different? The indigenously-manufactured nano DAP comes in liquid form. It is logistically easier to manage, and more cost-effective than the granular DAP. A 500 ml bottle of nano DAP, which costs Rs 600, is sufficient to cover one acre of land. In comparison, a single 50 kg bag of granular DAP costing Rs 1,350 is needed for one acre of wheat. For potatoes, 2.5 to 3 such bags are needed per acre. Apart from the lower price, farmers using nano DAP are likely to benefit from lower handling and transportation costs. Nano DAP was officially launched by IFFCO in 2023, following the introduction of nano urea in 2021. These innovations are a part of India’s broader strategy to reduce reliance on imported fertilisers. In the case of DAP, India uses around 10.5-11.5 million tonnes annually — but domestic production is only around 4-5 million tonnes, with the remainder being imported. Beyond benefitting farmers, indigenously-produced nano fertilisers are also set to ease India’s subsidy burden, which is pegged to be Rs 1.88 lakh crore in FY 2024. But their viability will eventually be determined based on results after large-scale adoption. Some have already raised question marks regarding nano DAP’s efficacy compared to the conventional granular form. What are PAU’s concerns regarding nano DAP? Punjab Agricultural University (PAU) scientists said that their experiments have found that nano DAP use resulted in a substantial decrease in yield of the wheat crop, compared to granular DAP. They said that they applied the nano fertiliser as per IFFCO’s guidelines, but that resulted in shorter plant heights, and sub-optimal results. PAU scientists also expressed similar opinions regarding IFFCO’s other nano fertiliser — nano urea. After two years of field experiments, they observed a decrease in rice and wheat yields. These findings were published in PAU’s monthly journal this January, with PAU scientists recommending that conventional urea not be replaced until further field experiments are carried out. In the last year, IFFCO manufactured around 6 crore bottles of nano DAP which can cover around 2.43 crore hectares of land. India has around 18 crore hectares of agricultural land in total. How has IFFCO responded to PAU’s criticism? Harmail Singh Sidhu, IFFCO’s marketing manager for Punjab, stated other agricultural Institutions like the Indian Council of Agricultural Research (ICAR) are also testing nano DAP (and nano urea) and unlike PAU, have not made a negative comment yet. He said that PAU scientists should conduct further trials using IFFCO’s recommendations on usage. “The Government of India (GoI) has recommended using nano DAP to replace only 25-50% of conventional DAP at the moment,” Sidhu said. “At least 50% of the recommended DAP dose, to be administered at the time of sowing, should comprise conventional DAP. The remaining 50% should be by nano DAP, to be used as a foliar spray after the crop’s leaves emerge,” he said. He added that nano DAP can also be used to treat seeds prior to sowing (5 ml per kg of seeds) for better results. “By even cutting down the use of granular fertiliser by 50% would greatly benefit the soil and environment,” he said. In Punjab, 70 lakh bottles of nano fertilisers (nano DAP and urea) have been sold since August 2021, Sidhu said.