Effect of water height on physiological and agronomical characteristics of rice cultivars in Ahvaz

In order to study the effect of plot water height on some agronomical and physiological characteristics of rice cultivars in Ahvaz, a field experiment was conducted experimental field of Ramin Agriculture and Natural Resources University in Ahvaz, in the during 2005- 2006 growing season. Treatments were arranged as a split-plot experiment in a randomized complete block design with three replications. Water height at four levels (5, 10, 15 and control: with water flowing) and three cultivars (Champa, Anbori and Danial) were the main plots and sub plots respectively. The results indicated that by increasing the height of plot water, the grain yield, number of grain in panicle and plant height increased, but at 15 cm water height a relative decrease in grain yield was seen. Also, by increasing plot water height, HI, number of tillers, water use efficiency and water temperature decreased but plot water height had no significant effect on 1000 grain weight. Among the cultivars, Danial and Champa had the highest and lowest grain yield, number of grain in panicle, tiller number and water use efficiency, respectively. If the water height, for decreasing of water usage, increasing water use efficiency and grain yield, in different cultivars is fixed, the 10 cm of plot water height inAhvaz region can be recommended.