Estimation of Crop Water Requirement and Irrigation Scheduling for Broad Bean (Vicia faba) Using CROPWAT 8.0

Abstract

Water is an essential natural resource that must be used efficiently, especially in the face of increasing demand across agriculture, industry, domestic supply, and environmental management. Sustainable water use is the need of the hour. Drip irrigation has emerged as a highly efficient method for agricultural water management, with a water use efficiency of 90–93%. This study focuses on the estimation of crop water requirement and irrigation scheduling for broad bean (Bush Dolichos variety) cultivated in red sandy loam soils of Bapatla, Andhra Pradesh, India. The study employed the FAO CROPWAT 8.0 model using long-term climatic, crop, soil, and rainfall data to estimate reference evapotranspiration, crop water requirement, and irrigation scheduling. Irrigation scheduling was planned at a two-day interval. Meteorological data over a 14-year period were analysed and input into the model. The estimated crop water requirement for broad bean was found to be 354.2 mm. These findings support efficient water resource planning and crop management under drip irrigation systems. By optimizing irrigation strategies and integrating plastic mulch into crop production systems, farmers can significantly improve water use efficiency while minimizing overall resource consumption without compromising crop productivity in comparable agro-climatic regions. Such practices contribute to substantial water savings, enhance precision in crop water management, and support resilient production systems under conditions of increasing water scarcity. In the context of the United Nations Sustainable Development Goals, these interventions directly advance SDG 2 (Zero Hunger) by sustaining agricultural productivity, SDG 6 (Clean Water and Sanitation) through efficient water use, SDG 12 (Responsible Consumption and Production) by reducing input wastage, and SDG 13 (Climate Action) by strengthening climate-resilient farming systems. Overall, this approach represents a practical and scalable pathway toward sustainable agriculture in water-limited environments, promoting efficient resource utilization, environmental stewardship, and long-term food security.