Effect of Planting pattern and water quantityon Potato Cultivation with Drip Irrigation in Mashhad

In order to study the effects of cultivation method and water quantities in drip irrigation on yield of potato, an experiment was carried out using a split plot based on randomized complete block design with 4 replications in Torogh Agricultural Research Station (Mashhad, Iran) for tow years (2001 and 2002). The main-plots were divided into 3 levels of irrigation: I1= 100, I2= 80 and I3= 60 percent of evapotranspiration. Sub-plots were 3 cultivation B1= distance between rows were 75 cm with one drip irrigation lateral, B2= two cultivation rows with distance of 35 cm and a lateral between them and distance between laterals was 135 cm and B3 = two cultivation rows with the distance of 45 cm and a lateral between them and distance between laterals was 150 cm. The results showed that Total yield in maximum irrigation (I1) was higher than I2 and I3. the B2 cultivation pattern had the highest total (19.7 t/h) and economic (18.5 t/h) yield. The B2 cultivation had the highest tubers yield (35-55 mm). Water use efficiency (WUE) of B2 cultivation with 3.54 kg/m3 was more than B1 and B3, but it was not significant. Water stress lead to reduction of total tubers yield, economic yield and WUE. maximum irrigation level (I1), had the most tubers yield (35-55 and bigger than 55 mm) and had significant difference with I2 and I3 irrigation treatment. WUE in maximum irrigation (3.53 kg/m3) was better than lower irrigation level in drip irrigation of potato and had significant difference.