Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/2012
Publication Date: 11/1/2012
Citation: Jabro, J.D., Iversen, W.M., Evans, R.G., Stevens, W.B. 2012. Water use and water productivity of sugarbeet, malt barley and potato as affected by irrigation frequency. Agronomy Journal. 104(6):1510-1516.
Interpretive Summary: The development of precise water management practices is one of the most critical aspects of irrigated agriculture for improving yield, maximizing crop water use efficiency (CWUE), meeting crop quality requirements, and reducing the adverse impacts on groundwater quality. A comprehensive study was conducted to compare the influence of two irrigation frequencies on crop water use (CWU) and CWP of sugarbeet, malt barley and potato on a sandy loam soil in the semiarid northern Great Plains. Statistical comparison analyses demonstrated that no significant differences due to irrigation frequency were found for yield, CWU, and crop water productivity (CWP) of sugarbeet (root and sucrose), malt barley and potato. The low frequency (LF) irrigation used 0.0061and 0.0021 m3 more water than high frequency (HF) irrigation to produce one kilogram of sugarbeet root and malt barley grain, respectively, over the growing season on a sandy loam soil. An equivalent amount of irrigation water was used to produce 1 one kilogram of potato tuber under both LF and HF irrigation. The LF irrigation can be advantageous to sustain economic yield production for sugarbeet, malt barley and potato, improve water use, maintain environmental quality and reduce net economic input as well or better than other precise, costly and laborious spray irrigation methods such as HF irrigation practices when self-propelled automated sprinkler system is used on a sandy loam soil.
Technical Abstract: Successful irrigation management is one of the most important agronomic practices for achieving profitable yield and maximizing crop water productivity (CWP) while maintaining environmental quality by minimizing water losses to runoff and deep drainage. This study was conducted to compare the influence of two irrigation frequencies on crop water use (CWU) and CWP of sugarbeet (Beta vulgaris L.), malt barley (Hordeum vulgare L.) and potato (Solanum tuberosum L.) on a sandy loam soil in the semiarid northern Great Plains. A long-term study was designed to complete two full rotation cycles of a three-year rotation of sugarbeet, malt barley and potato under a linear-move self-propelled sprinkler irrigation system in a stripped-randomized complete block experimental design. The irrigation frequencies compared were: high frequency (HF) irrigation with biweekly application of small irrigation quantities, and the conventional low frequency (LF) with weekly application of large irrigation quantities. Irrigation frequency was varied based on either 15mm (HF) or 30 mm (LF) cumulative crop evapotraspiration replacements. Seasonal CWU amounts were determined using the water balance equation of sugarbeet, malt barley and potato under HF and LF irrigations for 2007, 2008, 2009, 2010 and 2011. No significant differences due to irrigation frequency were found for yield, CWU, and CWP of sugarbeet (root and sucrose), malt barley or potato. Small differences in CWU values between HF and LF irrigations were due to variations in soil moisture content in the soil profile and drainage losses below the 0.91 m soil depth. Conventional LF irrigation thus can sustain economic yield production, improve water use and reduce net economic input as feasibly as HF irrigation practices when a self-propelled automated sprinkler system is used on a sandy loam soil.