Improving Water and Fertiliser Use Efficiency in Potato Production: The Turkish Way

Turkey is the fifth largest exporter of potatoes, producing around 4.4 million tonnes of potatoes annually on about 154,000 hectares (ha). More than one third of the total production is grown in the Nigde-Nevsehir region, with an average yield of 40 t/ha. This is an arid and semi-arid region with light-textured, loamy sands and production is totally dependent on sprinkler irrigation that relies on residual groundwater provided by spring rainfalls. About 1400-1700 mm of water is required under sprinkler irrigation to achieve marketable potatoes, of which only 35% is taken up by crop roots in the top 90 cm of the soil. The remaining 65% is lost through runoff and downward water movement beyond the plant roots. This excessive use of water also reduces the efficiency of water-soluble nitrogen fertilisers, such as urea or ammonium sulphate, in providing nitrogen for potato production. The main challenges are to increase water and nitrogen fertiliser use efficiency by applying irrigation water mixed with fertilisers, also known as fertigation, to the right place, at the right time and in the appropriate amount. Through an IAEA technical cooperation project, the Turkish Atomic Energy Agency, in cooperation with the Nigde Potato Research Institute and the Soil and Fertilizer Research Institute, implemented innovative drip fertigation technology to improve water and nitrogen fertiliser use efficiency in potato production in the Nigde-Nevsehir Region. This technology reduced the amount of irrigation water needed by 50% and nitrogen fertiliser use by 40%, from 1000 kg nitrogen/ha to 600 kg nitrogen/ha.