Integrating deficit irrigation, crop modelling and Water–Energy–Food nexus to enhance durum wheat resilience in Mediterranean climate conditions

This study evaluates the effect of three water regimes: full irrigation (I100: 100% of Plant Water Requirement); reduced irrigation (I50: 50% of PWR); no irrigation (I0: rainfed), on durum wheat production in southern Sardinia. The crop performances were tested over two cropping seasons (2022–2023 and 2023–2024) and across two sites (sandy-clay and clay-loam soils). The following traits were considered: grain yield, protein yield, biomass, 1000-grain weight, test weight, protein content, gluten index and harvest index. Deficit irrigation improved grain yield by 53.5 and 65.4% for I50 and I100, respectively when compared to I0. Similar improvements have been registered for most of the traits analysed, with no statistically significant differences between I100 and I50. The agronomic approach was integrated with in situ monitoring, remote sensing and crop modelling with AquaCrop to track soil moisture dynamics, providing suggestions for irrigation decisions. This comprehensive framework led to a Water–Energy–Food analysis to assess costs and benefits of deficit irrigation. The WEF analysis confirmed the sustainability of durum wheat irrigation while Energy Use Efficiency analysis proved that I50 was comparable with I100, the former being even more efficient in 2023. This approach allows to assess the use of deficit irrigation as a tool to enhance durum wheat production in agricultural drought-prone areas in order to preserve staple food security in the Mediterranean region.