How site-specific fertiliser boosts yields, cuts waste

Thursday September 16 2021
Nitrogen fertiliser

On average, farmers’ average profit increased by $140 per hectare, which was achieved with about 18kg less nitrogen fertiliser per hectare. PHOTO | FILE


In what they described as “the first comprehensive systematic review comparing the site-specific nutrient management (SSNM) approach to farmers’ practise within smallholder cereal crop production systems in Africa and Asia,” the team of scientists said they had found that using this method “generated 12 percent higher yield and 15 percent greater profitability compared with traditional farmer practise.”

In the study titled, "Co-benefits of nutrient management tailored to smallholder agriculture," published in the September Global Food Security-Elsevier journal, the researchers said they compared the two fertiliser management practises for maize, rice and wheat. Farmers used on average 10 percent less fertiliser nitrogen, thereby improving nitrogen use efficiency and reducing losses to volatilisation, leaching and runoff, which lead to nitrogen pollution to the environment.

“Key results drawn from the study show that SSNM produced these benefits while saving an average of 18 kg N/ha, which is equivalent to a 10 percent reduction in the amount of nitrogen fertiliser. This reduced the risk of nitrogen loss to the surrounding environment,” said the researchers, adding, “Achieving triple-wins of high yields and profit in combination with lowering nutrient losses.”

On average, yield gains were 0.6 tonne per hectare (12 percent). Gross return increased by 12 percent, whereas gross return above fertiliser cost was 15 percent higher with SSNM compared with farmers' fertilisation practise (FFP).

On average, farmers’ average profit increased by $140 per hectare. This was achieved with about 18kg less nitrogen fertiliser per hectare. Besides field-specific tailoring of n amounts, the increased nitrogen use efficiency in SSNM was also due to differences in frequencies and timing of fertiliser application.

“We know of no other agronomic intervention that has increased crop yield, profitability, and nitrogen use efficiency across these cereal crops and geographies in such a robust manner,” said the researchers.