Winter wheat productivity and profitability depending on water supply in the semi-arid agroecological conditions

Abstract

Dmytro Maksymov, Pavlo Lykhovyd*, Viktor Chaban, Oleksandr Rudik, Gennadiy Karashcuk, Mykhailo Retman, Iryna Biliaieva, Oleksandr Kazanok, Mykhailo Kliuchevych, Larysa Kucher, Ihor Kovalenko and Valerii Kozyriev

Climate variability in semi-arid environments necessitates a comprehensive evaluation of agricultural inputs relative to yield and resource efficiency. A two-year field experiment was conducted in southern Ukraine to evaluate the performance of winter wheat (Triticum aestivum L., cv. Mudrist) under irrigated and rainfed conditions following a pea predecessor. Irrigation significantly increased plant height by an average of 10.25 cm and grain yield by 26.3% compared to the rainfed control. Thousand-kernel weight and yield stability also improved under irrigation. Furthermore, irrigation enhanced total water resource utilization, reducing Water Use Efficiency (WUE) values from 81.54 mm/t in the rainfed treatment to 77.13 mm/t under irrigation. From an economic perspective, irrigation produced an additional net profit of 77.24 USD/ha. However, due to a 26.4% increase in production costs, the Return On Investment (ROI) did not differ significantly between treatments. These findings demonstrate that while irrigation delivers clear agronomic and resource efficiency benefits essential for food security, its financial profitability is highly sensitive to seasonal precipitation. Dynamic supplemental irrigation management based on seasonal moisture forecasting is recommended to optimize both water use efficiency and economic returns. The developed multiple linear regression model allowed precise winter wheat yield prediction using the 1000-kernel weight and plant height at the earing phase with the R² score of 0.807 and mean absolute error of 0.209 t/ha.