Sugar Beet Irrigation Management.

Increasing climate variability and competition for finite water resources have resulted in a need to determine the effect of in-season water availability on sugarbeet production. Data from 3 studies over 8 years and 9 site-years was conducted at the USDA-ARS NWISRL in Kimberly, ID. The impacts of various water inputs ranging from approximately 125% to 10% of sugarbeet evapotranspiration on sugarbeet production were assessed. Water input amounts for the treatments were applied weekly based on estimated sugarbeet ET.  Irrigation supplemented precipitation to match the input treatments. In general, sugarbeet yields are reduced with decreasing water supply. However a quadratic regression model significantly related the normalized sugarbeet yield reduction for all cultivars and site-years over the range of sugarbeet ET inputs, indicating that reductions in yields from 100% ET were smaller at slight decreases in water inputs compared to greater water input reductions. This paper will present data related to root and sucrose yields under deficit irrigation. This data will be critical for agricultural system planning if/as water resources become scarcer in the future.