Investigation of irrigation water volume and water productivity of pomegranate orchards in different regions of Fars province

Irrigation water has a great impact on the yield and water productivity of pomegranate orchards. There is few information about the irrigation of pomegranate orchards in Fars province. In this study, yield, irrigation water volume, water productivity and the difference between irrigation water volume and gross water requirement were investigated. 40 pomegranate orchards in four main regions of pomegranate production in Fars province (Shiraz, Estahban, Neyriz and Arsanjan) were selected. Yield, irrigation water volume and water productivity were measured during one year (2020). Three scenarios of crop water requirement, Water National Document, Penman Montith method in the year of research and Penman Montith method based on long-term meteorological data were considered. The irrigation water volumes were compared with the water requirement by t-test in the regions and different irrigation systems. Results showed that the average yield, irrigation water volume and water productivity of the were 22.4 t/ha, 15133 m3/ha and 1.36 kg/m3, respectively. There was no significant difference in the volume of irrigation water in Shiraz, Estahban and Arsanjan, but for Neyriz with other regions were significant. The yield differences in the studied areas was not significant. The water productivity differences of Shiraz pomegranate orchards with the other three regions was significant, but the difference in water productivity of Arsanjan, Neyriz and Estahban were not significant. The differences between yield, irrigation water volume and water productivity in the two types of surface and drip irrigation systems were not significant. In general, the volume of irrigation water was less than the gross water requirement. The difference between the volume of irrigation water and the water requirement of National Water Document, Penman Monthith in the year of the research and long-term Penman Monthith were significant at the level of 1%, non-significant and significant at the level of 5%, respectively.