Comparison of Sweet Cherry Prunus avium L. Tree Water Requirements in the Regions of Isparta (Turkey) and Bydgoszcz (Poland)

The aim of the present research was to compare sweet cherry tree water requirements in the vegetation period (IV–X) in the regions of Isparta (Turkey) and Bydgoszcz (Poland). The comparative analysis included precipitation values in the regions of Isparta and Bydgoszcz in the years 1984–2014. The calculation model by Hargreaves modified by Droogers and Allen [5] was applied in order to estimate the reference evapotranspiration (ET0). Potential evapotranspiration, identified with sweet cherry tree water requirements, was determined using the method of plant coefficients proposed by Doorenbos and Pruitt [2]. In each of month considered, higher sweet cherry water requirements occurred in the Isparta region. The highest sweet cherry trees water requirements for the research period were reported in July and they amounted to an average of 238 mm and 118 mm for the Isparta and Bydgoszcz regions, respectively. Sweet cherry tree water requirements throughout were higher by 102% in the region of Isparta than in the region of Bydgoszcz. Higher irrigation requirements in the province of Isparta compared to the region of Bydgoszcz result mainly from the smaller amount of precipitation and differences in the distribution of precipitation during the vegetation period.