Assessing irrigation BMP for water conservation - alternate row irrigation

In 2001, the Arizona Department of Water Resources implemented an agricultural Best Management Practice (BMP) program. The program was designed to encourage the use of BMPs in irrigation with goal of increasing the efficient use of water resources on the farm. Several BMPs were identified through stakeholder meetings and meeting with researchers and scientists. One of the BMPs identified was alternate row irrigation for surface irrigation systems. This study was designed to determine the impact of alternate row irrigation on irrigation water applications and yield. There were two treatments, every row (ER) and every other row (EOR). Lint yield was 1652 kg/ha (1474 lb/ac) and 1611 kg/ha (1438 lb/ac) in 2006; 1795 kg/ha (1603 lb/ac) and 1902 kg/ha (1698 lb/ac) in 2007 and 1365 kg/ha (1219 lb/ac) and 1237 kg/ha (1104 lb/ac) in 2008 for the ER and EOR treatments, respectively. The irrigation water amounts were 187.7 cm and 162.3 cm (73.9 and 63.9 in.) in 2006; 151.4 and 137.2 cm (59.6 and 54.0 in.) in 2007 and 184.1 and 132.6 cm (72.5 and 52.2 in.) in 2008 for the ER and EOR treatments respectively. The results indicate that on an average the use of EOR saves about 30.5 cm (12 in.) of water.