An irrigation system used for flower production during five years, in the municipality of Atibaia, SP, Brazil, was evaluated. A sample of 25 used emitters were evaluated in laboratory for discharge pressure curve and manufacturer's variation coefficient at 50, 100, 150, 200, 250, 300, 350 and 400 kPa. Chemical, physical and microbiological water analysis were performed at three different points: water source, after filtration unit and at lateral end. The manufacturer's coefficient was 8.2%. The statistical uniformity of the emitter discharge rates was 73%; the hydraulic uniformity based on pressure distribution was 97% and the emitter performance variation was 26%. Water analysis results along with performance evaluation showed occurrence of emitter cloging causing low statistical uniformity of emitter discharge.
drip irrigation; emitter cloging; uniformity evaluation
