Efecto del régimen de riego en el rendimiento de alfalfa para corte en el Valle Central de Catamarca, Argentina

in the province of catamarca there is a large area planted with alfalfa. lack of knowledge of crop water requirements in this area constitutes a serious problem. an irrigation experiment was conducted in randomized blocks in valle central with four treatments and four replications. the treatments consisted in replenishing soil moisture content at different thresholds: 75, 50, 25 and 0% of the total soil water storage capacity. dry-matter production per treatment was evaluated in seven cuttings. results showed that when irrigating with a 75 and a 50% threshold, similar dry-matter yields were obtained equivalent to 25,674.4 kg ms.ha-1 and 24,215.4 kg ms.ha-1, respectively. significant differences were found (p < 0.0001) between the means of these treatments and the other two treatments. an irrigation threshold of 25% yielded less than16,366.7 kg.ha-1 and an irrigation threshold of 0% yielded less than 9,970.9 kg.ha-1. it can be concluded that alfalfa production is significantly reduced when irrigation intervals are very long.