تأثیر تنش خشکی و تراکم بر صفات کمی و کیفی دوگونه دارویی اسفرزه اواتا (Plantago ovata Forssk) و اسفرزه پسیلیوم (Plantago psyllium L.)

In order to investigate yield, yield components and quality traits of P. ovata and P. psyllium under water stress and plant density, two experiments were conducted at the Agriculture Research Field, University of Tehran, Karaj, in April 2005 and 2006. Two Factorial experiments based on randomized complete block design with three replications were used. The treatments were three levels of water stress including water witholding at flowering (Severe stress), water withholding at flowering with complementary irrigation at grain filling (Medium stress) and control, three levels of plant density (low, medium and high density), and two plantago species. Combined analysis results showed that seed yield, biological yield, mucilage percentage and mucilage yield significantly different in two years experiments. In both years, water stress significantly decreased seed thousand weight, biological and mucilage yield per hectare. Water stress also significantly increased mucilage percentage and swelling seed in both species. The highest seed yield (765 kg.ha-1) and biological yield (4079 kg.ha-1) observed in medium and high plant density, respectively. Totally, results of this experiment showed that seed yield and mucilage yield per hectare were higher in P. ovata in compared to P. psyllium. The highest mucilage yield observed in medium drought stress and plant density of 100 and 70 plants per square meter in P. ovata and P. psyllium, respectively.