Comparison of Grain Sorghum and Corn Productivity Under Limited Irrigation With Subsurface Drip.

In the High Plains Region of the United States, groundwater is quickly becoming a diminishing resource. Specifically in the Ogallala Aquifer, water available for irrigation has declined steadily since the middle of the 20^th century. In the Oklahoma Panhandle, corn (Zea mays) is grown to provide feed for the livestock industry in the area.  However, because of the declining water supply, focus has turned to finding a crop that can be grown in place of corn with a higher water use efficiency (WUE). Sorghum (Sorghum bicolor) has been shown to have a higher WUE than corn, while still being able to produce enough grain to support the livestock industry. This study utilized a randomized block split-plot design planted to corn and sorghum at four different well capacities. The well capacities for corn were 3000, 2250, 1500, and 750 liters per minute, while the sorghum capacities were 2250, 1500, 750, and 375 liters per minute. The plots were irrigated using a subsurface-drip system, which was scheduled to simulate a center-pivot irrigation system. The results of this study will help determine whether sorghum is a more economical choice than corn for producers in the Oklahoma panhandle.