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• The plastic film mulching with 75 mm deficit irrigation significantly improved the root growth and increased grain yield. • The RF system with plastic mulching regulating root growth distribution and soil respiration rate. • The RF system with 75 mm deficit irrigation enhanced soil water content, root growth, root bleeding sap and wheat production. Soil moisture status and knowledge of rooting systems are essential for improving winter wheat productivity in the semiarid areas. The ridge-furrow rainfall harvesting (RI) system in combination with deficit irrigation is the key strategy for improving winter wheat productivity. Therefore, a research trail we conducted during 2015–16 and 2016–17, on RI system where the amount of irrigation was decreased by half due to the rainfall harvesting, than that of traditional boarder irrigation (BI). The following two planting patterns were used (1) the RI system with (75, 37, 18, 0 mm) irrigation levels, and (2) BI planting pattern with (150, 75, 37, 0 mm) deficit irrigation levels. Results showed that under the RI 75 treatment soil water and soil respiration in topsoil increase significantly ; whereas there was reduction in ET rate that was (44.2%) and soil temperature; thus, therefore and the morphology of winter wheat rooting system owing to significant improvement in grain yield (14.6%) and WUE (64.8%) as compared to BI 150 treatment. This treatment improved wheat root tissue density (4.9%), root length ratio (16.3%), root mass ratio (8.3%) and root fineness (9.5%) as compared with conventional border irrigation. The RI 75 treatment produced significantly greater RWD, RLD, and RSD at 10–40 cm soil depth when compared with BI 150 treatment. The RI system increased the root bleeding sap rate and root dry weight as compared to BI planting pattern. Therefore, the RI system combined with 75 mm deficit irrigation can be an efficient water saving strategy in semi-arid regions due to increased soil moisture across the rooting zones, a resulting in higher WUE and wheat production. [ABSTRACT FROM AUTHOR]

Highlights • Exploiting winter wheat productivity and radiation use efficiency through ridge furrow system and supplemental irrigation. • Ridge and furrow with plastic film system have positive effect on improve LAI, radiation use efficiency and grain yield. • Simulated rainfall (200 mm) with 150 mm supplemental irrigation under ridge furrow system was appropriate. • Thus, it increased the yield, LAI and radiation use efficiency. Abstract Agricultural productivity in semi-arid regions of China relies on the ridge furrow (RF) micro rainfall harvesting system, and supplemental irrigation reduces damage caused by drought stress. However, the extent to which the interactive effects of supplemental irrigation and simulated rainfall conditions can further improve winter wheat production and radiation use efficiency (RUE) remains unknown. Therefore, a mobile rainproof shelter was used to explore the potential benefit of the RF system under four supplemental irrigation (150, 75, 37, 0 mm) levels and three simulated rainfall (275, 200, 125 mm) levels. Data collected over two years indicated that the interactive effects of supplemental irrigation (150 mm) with simulated rainfall concentration (200 mm) could significantly improve the LAI (88.8%), Pn value (21.3%), PAR interception efficiency (I n ; 34.1%), interception of PAR accumulation (IPAR) (58.9%), RUE (11.2%), and PAR capture ratio (97.1%), due to reduction in the PAR reflection ratio (45.2%), canopy light transmittance (LT) (78.5%), and PAR penetration ratio (83.8%), and significantly increase the grain yield (60.0%) as compared to that of the RF3 150 treatment. Consequently, this RF system significantly improved the grain yield, with earlier development and rapid plant growth during each growth stage of winter wheat, at each supplemental irrigation and simulated rainfall level. The results suggest that in semi-arid regions of China, where water shortage is a serious problem, the RF2 150 treatment should be adopted as standard farming practice for improving crop growth, LAI, photosynthesis, efficient conversion of intercepted solar radiation by apical dominance, IPAR, RUE, total DMA, and winter wheat production. [ABSTRACT FROM AUTHOR]

Knowledge of rooting systems and soil water status across rooting zones is important for stabilizing agricultural productivity in the semi-arid regions of China. In the present study, a mobile rainproof shelter trial was performed to find out the effects of cultivation mode on the temporal and spatial root growth distribution, soil water content, root respiration rate, and grain yield during 2015–2016 and 2016–2017 growing seasons. The two cultivation modes were: (1) the ridge furrow (RF) rainfall harvesting technique; and (2) traditional flat planting (TF). In addition, three simulated rainfall (1: 275, 2: 200, 3: 125 mm) and two deficit irrigation (150, 75 mm) levels were used. Our results showed that different cultivation modes with simulated precipitation levels significantly improved moisture content for wheat growth, improved root growth, and provided favourable conditions for higher wheat production. The RF 150 treatment with 200 mm rainfall significantly increased morphology of the wheat rooting system, especially in the top 40 cm soil layer compared with TF cultivation. The RF 150 treatment significantly increased root dry weight (47%), root tissue density (6.7%), root fineness (4.8%), root length ratio (20.3%), root mass ratio (27.3%), and grain yield (18.9%) of wheat at 200 mm rainfall than that of TF2 150 treatment. Root weight density, root length density, root surface area density, and root diameter were significantly higher under RF 150 treatment with 200 mm and 275 mm precipitation in the 40 cm soil layer and reached maximum values at the flowering stage. The root dry weight, root respiration rate, and grain yield were significantly improved under RF2 150 treatment, but there were no significant differences when the rainwater increased from 200 to 275 mm under both cultivation modes. Therefore, we suggested that the RF2 150 treatment is a suitable water saving strategy to improve temporal and spatial root growth distribution, resulting in higher grain yield in a dry-land farming system. [ABSTRACT FROM AUTHOR]