Water and energy efficiency in bean crop under center pivot irrigation

Sprinkler irrigation systems, mainly of the center pivot type, provide high productivity and profitability, but require the adoption of management practices that allow greater efficiency in the use of water and energy resources. The objective of the present study was to analyze the efficiency in the use of water and energy resources of the irrigation management in the cultivation of common bean crop under center pivot irrigation systems in the Northeast of Minas Gerais. The efficiency of the use of water and energy resources was verified by comparing the irrigations practiced and the irrigations simulated according to a spreadsheet of 7 rural properties, with irrigated bean cultivation by center pivot with more than 10 years of use and without the adoption of management of irrigation. For this, irrigations carried out by the farmers were monitored and the hydraulic characteristics of the pivots, soil physical-water properties and climatic and crop data (ETc) were surveyed. Comparison of performed and recommended irrigations, showed that 6 of the 7 pivots irrigated excessively, but with an efficient use of water and energy resources, between 78 and 99%. A pivot performed a deficient management, being considered inefficient, since they did not provide the minimum conditions required by the culture. The irrigation systems evaluated have a tendency to perform an excessive irrigation, despite the efficiency in the use of water and energy resources in general considered good.