No-Till and Direct Seeding as Sustainable Alternatives for Improving Soil Functioning and Wheat Performance in Semi-Arid Agro-Ecosystems

High temporal and spatial variability in rainfall, combined with inherent soil constraints and inappropriate agricultural practices, strongly limits crop productivity in semi-arid regions. Reduced and no-till systems are often promoted for their potential to enhance soil water conservation and improve crop performance. Under semi-arid conditions, we evaluated the responses of soil properties and durum wheat (Triticum durum Desf.) to two cultivation practices (conventional tillage (CT) and no-till with direct seeding (DS)) combined with four preceding crops, namely mechanical fallow, chemical fallow, legume, and wheat. The experiment was conducted on a farmer’s field during the 2021/2022 growing season, following three consecutive years of implementation of the tillage systems. CT resulted in significantly higher grain yield and yield components compared with DS. In contrast, thousand grain weight, straw yield, and morpho-physiological traits (relative water content, chlorophyll content, and flag leaf area) did not differ significantly between tillage systems. Preceding crops had no overall significant effect; however, wheat as a preceding crop enhanced tiller density and spike fertility. Under DS, legume preceding crops improved aboveground biomass, straw yield, and chlorophyll content. Soil hydro-physical properties showed no significant differences between treatments, although no-till soils exhibited higher compaction and lower hydraulic conductivity than CT. These patterns were supported by a significant negative correlation between bulk density and infiltration rate. Moreover, no-till soils displayed higher organic matter content and greater structural stability over time than conventionally tilled soils.