how does nitrogen and irrigation change the productivity of salicornia europaea in saline soil?

glasswort(salicornia europaea l.) as an important halophyte plant is capable to accumulate nacl in aboveground part (fully edible) in considerable quantity. to evaluate the effect of irrigation levels and nitrogen fertilizer on the yield of seed and oil, and also harvest index of glasswort, a split plot experiment was conducted based on randomized complete block design with three replications at the lake urmia marginal in 2012. treatments were irrigation regimes (irrigation after 20, 40, 80 and 120 mm of evaporation from a class a pan) as main plot and amount of nitrogen spraying (0, 5, 10, 15, 20 percent of urea (v/v) as sub plot. results indicated the significant interaction effect between irrigation and nitrogen on the yield of seed and oil, biological yield and harvest index of seed and oil. in well irrigated plants (irrigation after 20 mm evaporation), higher concentration of nitrogen spraying up to 10% caused to raise the yield of seed and oil, and biological yield. these yields were raised up by application of 15% nitrogen and then they were decreased. a significant increasing of yield (seed and oil) was observed at 15% of nitrogen spraying for the mild and mid (irrigation after 40 and 80 mm evaporation, respectively) water deficit stress. in conclusion, we found the foliar application of nitrogen (low environmental contamination) benefit for glasswortproduction, but in different optimum amount for each irrigation interval.