Joyce L. Eckhoff, Montana State Univ, Eastern Agric Res Center, 1501 N. Central Ave, Sidney, MT 59270 and Charles Flynn , Montana State Univ, Eastern Agri Res Center , 1501 N. Central Ave , , Sidney , MT 59270 .
Good nitrogen management is one of the most important aspects of a high-yielding, high-quality sugarbeet crop. Not enough N limits yield. Too much N reduces quality, can cause surface and ground water contamination and increases input costs. An irrigation management study showed that sugarbeet under sprinkler irrigation had higher impurity content, greater sucrose loss to molasses and lower extraction than flood irrigated sugarbeet. The objective of this study was to fine-tune nitrogen recommendations for sugarbeet produced under sprinkler and flood irrigation. Plots with varying rates of nitrogen were set up under a linear overhead sprinkler irrigation system and under furrow flood irrigation. Soil is Savage silty clay. Test sites were next to each other every year. Plots were planted to stand. Pesticides and irrigation water were applied as needed. Two wells that reached ground water were placed on each of the upper end and lower end of each irrigation system, for a total of four wells under each irrigation system. Ground water was sampled for nitrate-N content throughout the growing season. Sugarbeet petioles were regularly collected from each plot during the growing season and analyzed for nitrate-N concentration. When analyzed across 3 years, sugarbeet under flood irrigation had greatest root yield, sucrose yield, and extractable sucrose with 197 kg/ha available N. Sugarbeet under sprinkler irrigation had greatest root yield, sucrose yield, and extractable sucrose with 141 kg/ha available N. Impurities and sucrose loss to molasses continued to increase as applied N increased under flood irrigation. Impurities and sucrose loss to molasses were high with any rate of applied N under sprinkler irrigation. Sugarbeet petiole nitrate-N concentrations at all testing dates were slightly greater under sprinkler irrigation than under flood irrigation, although petiole nitrate-N concentrations under both irrigation regimes were less than 1000 ppm by the end of August.
See more of Poster Papers
See more of The Western Society of Crop Science (June 19-21, 2006)
