Soil Properties and Yield of Jerusalem Artichoke (Helianthus tuberosus L.) with Seawater Irrigation in North China Plain1

Irrigation with various dilutions of seawater can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture in the coastal semi-arid areas of the North China Plain. Jerusalem artichoke (Helianthus tuberosus L.) grown in a field experiment was irrigated with seawater diluted with freshwater from 2001 to 2003 to determine the feasibility of seawater irrigation in the Laizhou area. For treatments of CK (non-irrigation) along with seawater concentrations of 25%, 50%, and 75%, total dissolved solid (TDS) in the non-irrigated soil significantly increased (P ≤ 0.05) in both 2002 and 2003 and was 1.3 times higher in 2003 than in 2001. In the 25% and 50% seawater concentration treatments, TDS in 2001 was significantly greater (P≤ 0.05) than CK; however, TDS in these two treatments decreased by 34.9% and 40.1%, respectively, in 2003 compared with 2001. The sodium adsorption ratio (SAR) remained below 10 mmol1/2 L−1/2, indicating that alkalization was low with seawater irrigation. In 2001 and 2002, compared to CK and the irrigation treatment with 75% seawater, irrigation with 25% and 50% seawater increased the yields of Jerusalem artichoke. This meant that Jerusalem artichoke could be safely grown in salt-affected land of Laizhou area with 25% and 50% seawater irrigation.