Using a lysimetric station to determine the irrigation water requirements for chufa crop (Cyperus esculentus var. sativus)
Chufa, also known as tigernut, is a typical irrigated crop in Valencia (Spain). It is cultivated for its tubers, which are mainly used for producing a traditional refreshing drink called “horchata”. It is mainly furrow irrigated, using large amounts of water. Several studies have been carried out in the last years by the research team in which this contribution has been undertaken, in order to improve the irrigation efficiencies in chufa crop. Although the previously obtained improvements are considerable, they are not definitive, as the crop water requirements are still unknown. To enable growers to determine these water needs, it is necessary to determine the crop evapotranspiration. This experiment was carried out on an experimental plot of the Universitat Politècnica de València, within the traditional chufa cultivation area. This plot includes a lysimetric station, which enables the determination of the daily crop evapotranspiration. Furthermore, the plot is equipped with an agro-meteorological station, which provides the necessary parameters for determining the daily reference evapotranspiration through the FAO-56 Penman-Monteith method. The crop coefficient has been estimated relating the crop and reference evapotranspiration values, for the different growth stages. According to FAO-56, four growth stages were identified and their length determined as initial stage (21 days), development stage (76 days), mid-season stage (43 days), and late stage (29 days). The single crop coefficient values for the initial, mid-season and the end of the late growth stages were established as 0.25, 1.43 and 0.75, respectively. This contribution presents a first approximation to determine the single crop coefficient for chufa crop, and it is currently being continued under the economic support of Generalitat Valenciana [GV/2017/037], with the aim of determining the dual crop coefficient for chufa crop. The use of the crop coefficient will enable irrigation water doses to be adjusted to water requirements, thus reducing the volume of water applied and improve the irrigation efficiencies for the chufa crop.
Núria Pascual-Seva won an ISHS Young Minds Award for the best oral presentation at the II International Symposium on Root and Tuber Crops: Value Added Crops for the Next Generation at IHC2018 in Turkey in August 2018.
Núria Pascual-Seva, Centro Valenciano de Estudios sobre Riego, Universitat Politècnica de València, Camí de Vera, sn, 46022 Valencia, Spain, e-mail: firstname.lastname@example.org
The article is available in Chronica Horticulturae