Evapotranspiration of Irrigated Sunflower in a Semi-Arid Environment.

 

Sunflower (Helianthus annuus) is an alternative crop for the Southern High Plains typically produced under dryland; however irrigation offers greater potential for enhanced productivity and quality.  Sunflower [cv, S 672 NuSun (Triumph Dwarf)] was grown in 2009 at Bushland, Texas on two 4.2 ha fields each containing a precision weighing lysimeter ( 3 m by 3 m by 2.3 m deep, monolith) containing Pullman clay loam soil (fine, mixed, superactive, thermic Torrertic Paleustoll) on fields with slopes less than approximately 0.3% that were sprinkler irrigated.  Water use was determined by lysimeter water budgets.  Crop development was measured with periodic (~14 d interval) field plant samples for height, width, leaf area index and total biomass.  Final plant harvests determined dry matter, Achene numbers per head and mass, and seed soil quality.  Results on water use (evapotranspiration), yield, yield components, oil quality, and water use efficiency will be presented.