Brackish water irrigation in orchards: A review

The development and utilization of brackish water resources have emerged as effective strategies to alleviate freshwater scarcity and enhance water security in arid and semi-arid regions. The continued expansion of fruit tree cultivation in Northwestern China has further intensified agricultural water demand, making the diversification of irrigation water sources - particularly the rational use of brackish water - critical for the sustainable development of the fruit tree industry. This review systematically examines the potential of brackish water for irrigation in fruit tree production and evaluates the effects of irrigation water with varying salinity on fruit tree growth and development. Emphasis is placed on physiological responses, including growth characteristics, changes in osmoregulatory substances, ion transport and distribution mechanisms, and management practices for saline water irrigation. In view of the existing knowledge gaps in our understanding of the mechanisms underlying tolerance of crops to salinity, salinity adaptation thresholds, fruit tree-soil interactions, brackish water irrigation management, and long-term ecological impacts of saline water irrigation, future research should prioritize comprehensive and long-term experimental studies of these areas. Improving our understanding of salt tolerance mechanisms, innovating saline irrigation technologies, and adaptive management strategies for different fruit tree species will help improve sustainable utilization of brackish water resources, providing theoretical foundations and technical guidance for developing green, water-saving agriculture, and the safe and efficient use of brackish water in this region.