The Effect of Soil Moisture Level on the Yield, Consumptive Use of Water, and Root Development by Sugar Beets

Abstract

AbstractExperiments were conducted to determine the effect of soil moisture level on yield, consumptive use of water and root development by sugar beets. The studies were made on areas with two water table depths to determine generally the extent to which sugar beets can use moisture in the moist zone immediately above a water table.When sugar beets were allowed to remove 43, 75 and 95% of the available moisture in the root zone prior to irrigation, yields were 23.4, 22.0, and 16.9 tons per acre, respectively, on an experiment where plants could not obtain ground water. In a second experiment on an area with a water table at 4 to 4.5 feet below the soil surface, yields were 22.9 and 23.5 tons per acre when plants were allowed to extract 54 and 66%, respectively, of the available moisture prior to an irrigation. A third treatment not receiving irrigation, but drawing heavily on ground water, yielded 20.1 tons per acre.Consumptive use of water for the growing season by sugar beets was 23.4, 22.5 and 19.0 inches, depending on whether 43, 75 or 95% of the available moisture was removed prior to an irrigation. The largest amount of water was lost from the surface foot of soil in all periods of measurement with progressively smaller amounts from deeper depths on the two wetter treatments. Moisture use was related to the depths containing available moisture in the dry treatment.Moisture level had no effect on the rate of root extension or the shape of the commercial root.