Effects of plant spacing and irrigation intervals on yield and essential oil percentage of (Satureja bachtiarica Bunge.)

Satureja bachtiarica Bunge. as a medicinal plant belongs to Lamiaceae family. In order to evaluate the effects of different plant spacing and irrigation intervals on yield and quality of essential oils of plant foliage, a study carried out during 2010 to 2012 at research farm of Agriculture College, Ilam University, using a factorial design. factors were four plant spacing (15×15, 15×20, 20×20 and 20×25 cm) and four irrigation intervals (every day, every other day, after four days and after six days). Analysis of variances showed that irrigation intervals and planting distances had significant effects on dry weight, total antioxidant and oil yields. The highest dry and fresh weights were observed in treatment of every day irrigation and 15×15 cm planting space. The highest essential oils yield recorded in treatment of every four days irrigation and 20 × 20 cm planting space. However, oils yield of different treatments varied from 0.30 to 0.87 percent. The highest antioxidant activity (78.49 percent) obtained with the treatment of every four days irrigation and 20 × 20 cm spacing.