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The Decision Support System for Agrotechnology Transfer – Cropping System Model was used with an objective to evaluate maize (Zea mays L.), winter wheat (Triticum aestivum L.) and grain sorghum (Sorghum bicolor L. Moench) yield, crop water productivity (CWP) and return after variable cost (RAVC) under different combinations of irrigation interval/capacity and plant available soil water (PASW) thresholds on three soil types in southwestern Kansas. Maize, grain sorghum and winter wheat yields were maximized under irrigation capacity of 4.2–6.3, 3.1–4.2 and 2.5–3.1 mm/d, respectively. The lowest and highest values in the range corresponded to silt loam and fine sand soils, respectively. For maize, maximum RAVC ($630–710/ha) and CWP (25–27 kg/ha/mm) were achieved with a relatively shorter irrigation interval (25 mm/4–8 d). RAVC values for grain sorghum and winter wheat were not substantially affected by irrigation interval. The RAVC for grain sorghum and winter wheat ranged from $150 to $200/ha and $310 to $370/ha, respectively. The CWP of grain sorghum peaked at shorter irrigation interval (25 mm/6–8 d), whereas, high CWP of wheat was simulated even at longer irrigation interval (25 mm/26 d). Overall, for winter wheat and grain sorghum, irrigation strategy for attaining higher RAVC values is different from irrigation strategy for attaining higher yield. Whereas, for maize, irrigation strategy for higher yield is the same as that irrigation strategy for higher RAVC. This study guides producers to identify and prioritize the most suitable irrigation strategy for optimizing yield, CWP and/or income while enhancing sustainability of environment and management of ground water. The present work assumes all factors except water are optimal and findings are sensitive to dynamics of price changes, productivity levels and variations in crop management and climate. • Irrigation scheduling for maize, winter wheat and grain sorghum was evaluated. • Yield, crop water productivity (CWP) and income were used as evaluation criteria. • For maize, maximum income, CWP and yield were met at shorter irrigation interval. • Irrigation strategy for high income in wheat is different from that for high yield. • Grain sorghum and wheat income was not substantially affected by irrigation. [ABSTRACT FROM AUTHOR]

• Water conservation is the best way to increase water management efficiency in agriculture and reduce potential negative environmental impacts. • Residue improves soil tilth and adds organic matter to the soil as it decomposes. • Crop residue can reduce the rate of water evaporation and runoff, increase penetration of water and therefore improve soil water conservation. Wheat (Triticum aestivum L.) residues and water management are major problems in southern part of Iran where irrigated wheat-corn (Zea mays L.)-wheat rotation is a common practice. A 2-year (2015–2016) field experiment was conducted as a split plot design with four replications to determine the influence of different irrigation regimes (50, 70, and 100% of water requirement) and wheat residue rates (0, 25, and 50%) incorporation into the soil on sweet corn (Zea mays L V. Saccharata) growth, grain yield, and some soil properties at School of Agriculture, Shiraz University, Shiraz, Iran. The results showed that the highest plant height (187.12 cm) and leaf area index (3.49) were obtained when the crop was normally irrigated (100% of water requirement) and sown into the 25% incorporated wheat residues. Furthermore, canned yield (68%) and water use efficiency (WUE) increased with normal irrigation and 25% residue incorporation compared to the 50% wheat residue rate. The highest grain protein (14.67%) was achieved under incorporation of either 25 or 50% wheat residue into the soil, while the highest grain sugar (2643.5 mg g−1) was obtained when the crop was moderately irrigated (70% of water requirement) with 25% residue incorporation into the soil. The highest soil nitrogen (N) and soil organic carbon (SOC) were achieved with normal irrigation and 50% residue incorporation in both years.In general, adopting an adequate rate of wheat residue (between 25%–50%) accompanied by decreasing irrigation volume to 70% water requirement of corn is recommended in semi-arid agroecosystems. [ABSTRACT FROM AUTHOR]