The Role of Agricultural Gypsum Application in Improving Some Soil Properties and its Impact on the Productivity and Quality of Date Palm Fruits in Waddan Region (Al-Jufra)

Abstract

This study aimed to investigate the use of agricultural gypsum as a strategy to improve soil chemical properties and fertility, and its impact on the productivity, physical characteristics, and fruit quality of 12-year-old date palms in the Waddan area of   the Jufra region.

A field and laboratory experiment was conducted comparing two statistical treatments. The first treatment (T1) consisted of the common normal agricultural practice in the region, adding traditional organic fertilizer (fermented sheep manure at a rate of 75 kg/palm) without any other additives. The second treatment (T2) involved an integrated intervention, adding the same quantity of organic fertilizer combined with high-purity agricultural gypsum at a rate of 3 kg/palm in three equal applications during the growing season

Laboratory results for soil environment after the application of the integrated treatment (T2) showed a highly significant chemical improvement. The pH decreased from the critical alkaline value of 7.95 to a safe range close to neutral at 7.65. The electrical conductivity (EC) decreased significantly from ds/m².85 to ds/m². Consequently, total dissolved solids (TDS) decreased by 467. Meanwhile, organic matter (O.M.) increased dramatically from a low initial percentage of 0.22% to 1.78%. Calcium sulfate (CaSO₄) also showed a sustained increase from 0.42% to 1.18%, while calcium carbonate (CaCO₃) did not show a statistically significant change (p = 0.062).

These soil improvements had a positive and substantial impact on the fruit's productivity and physical characteristics. The yield per palm tree saw a statistically significant increase (p = 0.000), rising from 95 kg in the first treatment to 124.80 kg in the second treatment. This increased the total yield of the ten palm trees from 950 kg to 1250 kg, representing a 31.37% improvement. Furthermore, the physical quality of the fruit improved significantly. The weight of 50 dates increased from 550 g to 850 g, the length of the fruit increased from 3.90 cm to 4.65 cm, and the cross-sectional diameter of the fruit increased from 20.20 mm to 24.50 mm..