Enhancing water use efficiency in pulse-based cropping systems: A review

Abstract

Pulses are an essential component of sustainable agriculture due to their ability to fix atmospheric nitrogen, improve soil health, and contribute to dietary protein security. Predominantly grown under rainfed conditions in South Asia and Sub-Saharan Africa, pulse production is highly sensitive to water availability and climate variability; thus, improving water use efficiency (WUE) is imperative for ensuring productivity and resource sustainability. WUE in pulses can be defined as the biomass or economic yield produced per unit of water used through evapotranspiration. Recent research highlights several technological and agronomic approaches to enhance WUE in pulse-based cropping systems. These include the adoption of precision irrigation methods like drip and sprinkler systems, regulated deficit irrigation, mulching to reduce evaporation losses, and conservation tillage practices. Crop diversification through intercropping and rotations with cereals has also shown promise in optimizing water utilization. Furthermore, breeding programs have developed drought-tolerant and short-duration varieties, which exhibit higher transpiration efficiency under limited water conditions. Incorporating ICT tools, real-time weather data, and soil moisture sensors has enabled site-specific irrigation scheduling, thereby improving on-farm water management. However, challenges such as poor adoption of micro-irrigation technologies, limited access to extension services, and high installation costs persist, especially among smallholder farmers. Therefore, a multi-disciplinary and region-specific approach, encompassing research, policy, and farmer education, is crucial for translating water-saving technologies into sustainable pulse production systems.