Precision irrigation scheduling improves water productivity and economic indicators in young high-density apple orchards

• Sensor-based irrigation scheduling enhances economic water and energy productivity. • RDI maintains yield and quality while reducing water consumption. • SDI conserves water but slightly reduces yield and quality. • Shading nets reduce water consumption and mitigate water stress effects. • Economic indicators show the profitability of precision irrigation strategies. Water shortages in arid and semi-arid regions have caused traditional horticulture to move towards high-density orchards. While water productivity (WPc) in high-density orchards has been studied in various contexts, a comprehensive analysis of the key factors influencing it in a water-limited region, which also considers economic indicators, has been lacking. This research innovates by combining the effects of sensor-based precision irrigation and Deficit Irrigation (DI) and shading net on WPc, Economic crop Water Productivity (EWPc), and Economic Energy Productivity (EEP) indicators in high-density apple orchards. This experiment was carried out in northeastern Iran during two growing seasons in 2021–2022, in comparison to EvapoTranspiration-based Irrigation Scheduling (ETS) and Soil Moisture-based Irrigation Scheduling (SMS), as well as shading net treatment (with (S1) and without (S0) shading net) along with the irrigation strategies that included Full Irrigation (FI), Regulated Deficit Irrigation (RDI), and Sustainable Deficit Irrigation (SDI). FI applied 100 % of the crop water requirement at all growth stages, while RDI supplied 60 % of the water requirement between 55 and 105 days after full bloom, maintaining 100 % irrigation at other stages. In contrast, SDI provided 60 % of the water requirement throughout all growth stages. Results showed these techniques and strategies were able to increase WPc by varying amounts, such that the highest WPc was observed with SDI-S1 (11.5 kg/m³) and SDI-SMS (12.7 kg/m³) treatments in 2021 and RDI-SMS (15.9 kg/m³) and RDI-S1 (10.8 kg/m³) treatments in 2022. Similarly, under RDI-S1-SMS (1.3 $/m³ and 2.8 $/m³) treatments, the EWPc values reached in two years, respectively. These findings gained further insights into optimizing WPc and economic indicators for sustainability applications in horticultural development in water-limited regions.