Impact of Deficit Irrigation Strategies Using Saline Water on Soil and Peach Tree Yield in an Arid Region of Tunisia

• Published in: Agriculture (Basel) Vol. 14; no. 3; p. 377
• Main Authors: Toumi, Ines, Ghrab, Mohamed, Zarrouk, Olfa, Nagaz, Kamel
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2024
• Subjects: Agricultural production; Agriculture; Aquatic resources; Arid regions; Arid zones; Climate change; Crop production; Crop yield; Drip irrigation; Ecosystems; Emitters; Food security; Food supply; Fresh water; Freshwater resources; Fruit trees; Fruits; Growing season; Irrigation; Irrigation water; Leaching; Loam soils; low-quality water; Management tools; Moisture content; Orchards; P. persica; Precipitation; production; Rainfall; Saline soils; Saline water; Salinity; Salinity effects; salinization; Salt; Sandy soils; Soil moisture; Soil properties; Soil salinity; Soil texture; Soil water; Soils, Salts in; Sustainability; Sustainable development; Texture; Trees; Tunisia; United Kingdom; warm area; Water conservation; Water content; Water management; Water quality; Water requirements; water restriction; Water scarcity; Water shortages; Water supply; United Kingdom; Tunisia
• ISSN: 2077-0472; 2077-0472
• DOI: 10.3390/agriculture14030377

Sustainable fruit orchard development in arid areas is severely affected by the scarcity of fresh water. To mitigate the lack of fresh water, the use of low-quality water for irrigation is becoming a common practice in several margin areas. However, salinity is considered one of the most important environmental constraints limiting the successful crop production. Therefore, the effects of deficit irrigation strategies using saline water (3.1 dS m−1) on soil water content, soil salinity, and yield of commercial peach orchard were investigated. Three irrigation treatments were considered: a Control, full irrigated (FI); and partial root-zone drying (PRD50); and deficit irrigation (DI) strategies irrigated at 50% ETc. These levels of water supply allowed for contrasting watering conditions with clear distinction between irrigation treatments. The differential pattern in soil moisture was accompanied by that of soil salinity with an increase in all FI treatments (16–25%). The results indicated that soil salinity increased with increasing water supply and evaporative demand during the growing season from January (3.2 dS m−1) to August (6.6 dS m−1). Deficit irrigation strategies (DI, PRD50) induced more soil salinity along the row emitter compared to the Control due to insufficient leaching fractions. By the end of the growing season, the soil salinity under long-term saline drip irrigation remained stable (5.3–5.7 dS m−1). An efficient leaching action seemed to be guaranteed by rainfall and facilitated by sandy soil texture, as well as the high evaporative demand and the important salt quantity supplied, which maintain the deficit irrigation strategies as valuable tools for water saving and improving water productivity. The significant water saving of 50% of water requirements induced a fruit yield loss of 20%. For this reason, DI and PRD50 could be reasonable irrigation management tools for saving water and controlling soil salinity in arid areas and on deep sandy soil.