salinity effect on water relation, osmoregulators and yield of three plantago species

in order to evaluate the effect of salinity on water relation, ion accumulation, solute sugar, proline content, chlorophyll florescence and seed yield of isabgul (plantago ovata), french psyllium (p. psyllium) and great plantain (p. major), an experiment was conducted at vali-e-asr university of rafsanjan in 2010. this study was carried out as factorial experiment based on randomized complete block design with four replications. treatments were included four salinity levels (9, 15 and, 21 ds/m and control with distilled water) and three plantago species (plantago ovata, p. psyllium and p. major). results showed significant effect of salinity, species and interaction between them on relative water content (rwc) which was decreased in response of higher salinity in all species with different trend in species. higher concentrations of salt led to higher leaf na+ content and lower k+, ca++ and mg++ content. despite of species, proline content and solute sugar were not significantly affected by salinity in all species. the highest and the lowest seed yield of great plantain were observed in control and 21 ds/m, respectively. no seed harvested from french psyllim in 21 ds/m. in general, among three species, great plantain had higher stability in ion balances, rwc and seed yield in salinity condition.