Effect of Subsurface Water Level and Irrigation Intervals on Hassawi Rice (Oryza sativa L.) Production on a Sandy Loam Soil

A 2-year experiment was conducted using 84 cylindrical metal barrels, each 80 cm in diameter and 120 cm in height. Barrels were packed with sandy loam soil to evaluate the effect of three subsurface water levels (30, 70, and 100 cm) and four irrigation intervals (daily, every second day, every third day, and every fourth day) in a completely randomized design on growth and production of Hassawi rice (Oryza sativa L.) cultivar. The 30-cm subsurface water level (SW L) gave the highest grain yield. However, yield decreased as SW L increased. On the other hand, the four irrigation intervals showed significant increase in grain yield as the frequency of irrigation decreased. All yield components were positively affected by increasing irrigation frequency. The most important was found to be the 100-grain weight. The increase in grain yield was associated with the increase in plant height, plant fresh weight, plant dry weight, and weight of 100 grains. The interaction between SW L and irrigation intervals reveal...