Impact of soil and water salinity on Deglet Noor dates quality

Abstract The Ziban region in southeast Algeria is known for its soils, which have varying degrees of salinity, and where the date palm is mainly cultivated. This study aims to highlight the impact of soil and irrigation water salinity on Deglet Noor date quality criteria. Following field surveys in 2022, sampling sites were selected according to the variable degree of salinity observed in ten date palm groves, where the date samples each were collected from adult palms. Various physicochemical analyses were carried out on soil: soil pH (SpH), soil electrical conductivity (SEC), total (TL) and active limestone (AL), on water: water pH (WpH) and water electrical conductivity (WEC), and on dates: date length (DL), date weight (DW); pulp weight (PW), date diameter (DD), water content (WC), date pH (DpH), date electrical conductivity (DEC), total sugar (TS), reducing sugars (RS) and sucrose (S). The quality assessment was made according to the international standards. Our results showed that for irrigation water, the pH was slightly acidic to basic (WpH= 6.83-7.9), and salinity varied from high to extremely saline (WEC= 1.5-8.5ms/cm). The soil was moderately acidic to neutral (SpH=5.96.61), saline to highly saline (SEC= 1.25-3.4ms/cm), and slightly to moderately calcareous with total and active limestone values ranging from 3.82 to 9% and 13.2 to 20% respectively. An important variation was observed in dates morphological (DL: 3.70-4.42cm; DW: 9.01-14.39g; PW: 8.30-13.32g and DD: 1.71-2.13cm) and physicochemical characteristics (DpH: 5.56-6.78; DEC: 1.4-2.4ms/cm; WC: 1338%; TS: 50.6-71.9%; RS: 17.1-48.6% and S: 6.4-46.3%). Also, very strong correlations were evidenced between the characteristics of dates, soil, and water, particularly those related to the morphological traits and sugar nature. Finally, our study linked water and soil quality to date quality, which helps the farmer better decide on the site and cultivation practices before setting up a palm grove.