The ridge-furrow system combined with supplemental irrigation strategies to improves radiation use efficiency and winter wheat productivity in semi-arid regions of China

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.