Response of Two Potato Varieties to Irrigation Methods in the Dry Mediterranean Area

Due to water scarcity and dry Mediterranean conditions, improving water use efficiency is a major challenge for sustainable crop production and environment protection. Field experiments were conducted for two consecutive years (2010 and 2011) to assess the effects of variety and irrigation method on potato crop, following a 2 × 4 factorial experiment type arranged in a split plot design with two spring potato varieties (Spunta and Marfona), and four irrigation methods (drip irrigation with two modes of dripper spacing/dripper flow: 30 cm at 4 l/h and 60 cm at 8 l/h, sprinkle irrigation, and furrow irrigation), with three replicates. Potato was irrigated when soil moisture in the active root depth was within the range of 75-80% of field capacity as determined by the neutron probe technique. Results did not show any differences between both varieties. Moreover, no differences in marketable yield, total dry matter, and harvest index were found between irrigation methods. However, results showed that sprinkle irrigation significantly enhanced nitrogen use efficiency. Furthermore, both water productivity and irrigation water use efficiency were significantly increased under drip irrigation compared with the other irrigation methods. They were about twice those under furrow irrigation, indicating that the employment of drip irrigation method can effectively address water shortage and sustainable potato production, in the dry Mediterranean region.