Pollination Using a Saline Liquid Pollen Suspension Improves Fruit Set, Sugar Profile, and Ionic Balance in Mech Degla Date Palm (Phoenix dactylifera L.)

The oasis agricultural system is facing challenges due to water scarcity, aridity, and salinity. Conventional date palm pollination remains costly under these conditions. This study evaluated the pollination of Mech Degla, a dry cultivar, using liquid suspension with irrigation water as an alternative to distilled water. A randomised design was used. Three treatments were applied: T1 1.5 g L−1, T2 3 g L−1 (mixed), and T3 2 g L−1. Each female inflorescence received 250 mL of suspension, equivalent to 3 L per palm. The control was traditional pollination with three male spikelets without water. The study was conducted over two consecutive seasons and the irrigation water used was characterised by soluble calcium 5.2 mEq L−1, a pH of 7.75, and an electrical conductivity (EC) of 2.08 dS m−1. The results demonstrated that T1 was significantly superior to the control, with fruit set and retention rates reaching 97.17% and 87.67% compared to 76.30% and 69.28% (p < 0.001). T3 demonstrated the optimum weight (13.22 kg) and length (120.33 cm). T2 total fixed sugars (82.71%, 2018) and reducing sugars (72.14%). T3 improved the K+/Na+ ratio. Liquid suspension pollination using irrigation water is a promising alternative that uses moderately saline water and can be integrated into arid oasis practices.