Deficit irrigation strategies for maximizing economic returns in water-limited wheat production

Abstract:

Deficit irrigation is to water management what a household budget is to personal finance: it accepts that resources are limited and allocates them where the return per unit is highest. This research tested four irrigation levels—full irrigation (100% crop evapotranspiration, ETc), 75% ETc, 50% ETc, and rainfed control—on winter wheat (Triticum aestivum L., cv. AKAW-4627) at Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Maharashtra, over two rabi seasons (2021–22 and 2022–23). The 75% ETc strategy reduced water applied by 23.7% relative to full irrigation while lowering grain yield by only 8.5% (4.31 vs. 4.71 t ha⁻¹). Water productivity peaked at 1.83 kg m⁻³ under 75% ETc compared with 1.42 kg m⁻³ for full irrigation. Net returns were highest at 75% ETc (42,380 INR ha⁻¹, BCR 2.47). The 50% ETc level saved 47% of water but cut yield by 27.6%, making it economically inferior. These results position the 75% ETc strategy as the optimal trade-off between water saving and economic return for wheat in semi-arid Maharashtra.