the effect of water stress on yield, yield components and quality characteristics of plantago ovata and plantago psyillium

abstract in order to investigate the response of two species of p. ovata and p. psyllium to water deficit. the experiment was conducted during 2009 growing seasons in the agriculture research station ferdowsi of mashhad. for this purpose a split plot experiment based on complete randomized block design with three replications was used. four irrigation levels (4000, 3000, 2000, 1000 m3/ha) allocated in the main plots and two species of plantago (p. ovate, p. psyillium) were as sub plots. criteria such as spike length, number of spikes per plant, number of seeds per spike, 1000-seed weight, straw and seed yield were measured accordingly. three quality characters namely amount of mucilage, swelling factor and swelling rate per gram mucilage were also measured. the results indicated that number of spikes per plant, number of seeds per spike, 1000-seed weight, seed yield were significantly affected by irrigation levels. the maximum value of spike length, number of spikes per plant, number of seeds per spike, 1000-seed weight was obtained in irrigation level of 4000 (m3/ha), and the maximum value of straw and seed yield in p. ovatea was obtained in irrigation levels of 4000 (m3/ha) and 3000 (m3/ha), respectively and to p. psyllium was obtained in irrigation level of 3000 (m3/ha) and 4000 (m3/ha), respectively. the maximum amount of mucilage and swelling factor were obtained for both species were obtained irrigation level of 2000(m3/ha) and the maximum swelling rate per gram mucilage for both species were obtained irrigation level of 1000 (m3/ha).