Growing Rice With Less Water

Effective and efficient irrigation practices are critical to successful rice production and to the sustainability of rice production. To better understand how to address the issue of water management in rice we initially installed water flow meters on two studies that were designed to evaluate disease incidence using fertility, variety/hybrid, and water management as treatment variables. One study evaluated six varieties/hybrids over a range of nitrogen levels. We found that increased nitrogen levels resulted in increases in the time varieties/hybrids were flooded and that to best describe this effect we needed to utilize a detailed growth-staging system. A second study evaluated four cultivars/ hybrids under water management options of flood, row, row-flood, flood-row and two nitrogen fertility levels. This study showed that water savings were possible and that each variety/hybrid responded differently to all treatments and to describe these differences we needed to intensify our use of growth-staging. In 0 a study using two hybrids and six water management systems was initiated. Main plot irrigation treatments are: ) flood, ) row/40%, 3) row/ 0%, 4) IWD/40%, IWD/ 0%, and IWD/40%-flood. Row management consisted of planting rice on beds and irrigating down a furrow between the beds while intermittent wetting and drying (IWD) consists of flooding the field to a 0-cm depth and allowing the water to recede and the field to dry to the designated percentage of field capacity and then flooding the field to a 0-cm depth. This process is repeated throughout the season while the row watered treatment is watered each time the soil dries to the designated percentage of field capacity. Our 0 data indicated significant water savings were possible using the IWD approach while row watering resulted in lower grain yields.