Grain Sorghum Under Subsurface Drip Irrigation As Influenced By Row Orientation.

This study was conducted to determine the influence of row configuration and population on grain sorghum yield and irrigation water use efficiency in the Southern High Plains. The hypothesis for the study is that crop row orientation and population influences yield and irrigation efficiency. The study was conducted at the Oklahoma State University research station in Goodwell, Oklahoma. Three irrigation treatments of 50%, 75%, and 100% of sorghum’s evapotranspiration demand will be used.  At 100 % irrigation grain sorghum will be planted at 222,000 and 267,000 seeds/ha at 75% irrigation it will be planted at 154,000 and 185,000 seeds/ha and at 50% irrigation it will be planted at 79,000 and 99,000 seeds/ha.  Canopy will be monitored twice per month using drone imaging 3 meters above the canopy. Plant height and growth stage will be taken during the same period.  The SDI tape is placed on 152 cm spacing with two rows irrigated with each tape.  The row configurations include rows planted 38, 25 or 13 cm from the tape.  The 13 cm treatments contain an additional row at 76 cm from the tape.  At the end of the growing season, evapotranspiration (ET) will be calculated from the local Mesonet site and FAO crop coefficients for sorghum. It is expected that this research will be beneficial in demonstrating the importance of proper irrigation and alternative row configurations on crop yield and irrigation water use efficiency.