Effect of Water Table Management and Irrigation on Potato Yield

Abstract

In Canada, the Province of Manitoba is the second largest potato producer after Prince Edward Island. Potato is a moisture-sensitive crop, and excess or inadequate soil water content can adversely affect the yield and quality. Potato in Manitoba experiences periods of excess as well as insufficient water content within the soil profile during the growing season. The objective of this study was to compare the effect of four different water management treatments on potato yield in a fine sandy loam soil in southern Manitoba: controlled drainage with subirrigation (CDSI), free drainage with overhead irrigation (FDIR), no drainage with overhead irrigation (NDIR), and no drainage with no irrigation (NDNI). In November 2009, tile drains were installed at a depth of 0.9 m. CDSI was done through drainage control structures with a target water table depth of 0.6 m. Overhead irrigation was done using a traveling gun. Groundwater level, drainage discharge, and potato yield data were collected during the 2010 and 2011 growing seasons. In 2010, potato yield was not found to be significantly different between the treatments due to the large variability between the replicates. However, in 2011, potato yield from the FDIR treatment was significantly higher compared to NDNI and CDSI (p <0.05). The NDNI treatment yield was significantly lower (p < 0.05) than the other three treatments. When compared with NDNI, the other treatments showed a yield increase of 15% to 32%. Maintaining adequate soil moisture by overhead irrigation was most effective for increasing potato yield when rainfall is inadequate.