Effects of seed priming with salicylic acid and ascorbic acid grain yield and yield components of sunflower under water deficit conditions

In order to study the effects of seed priming with salicylic acid and ascorbic acid on grain yield and yield components of sunflower under water deficit conditions, an experiment was conducted in a split plot factorial experiment with three replications, at 2014-2015 crop season. First factor was irrigation in two levels (normal and water deficit condition) in the main plots and the factorial combination of ascorbic acid levels (control, 50 and 100 ppm) and salicylic acid levels (control, 100 and 200 ppm) were in subplots. The results of the treatments mean comparison showed that the water stress decreased seeds number of head (18.44%), 1000 grain weight (17.44%), grain yield (40.86%) and oil yield (63.53%). Among treatments of interaction between irrigation and salicylic acid, the highest rate of Number of seeds per capita (1197.11), grain yield (10.10 ton/ha), oil yield (4.98 ton/ha), was belonged to seed priming with 200ppm salicylic acid in normal condition. Among irrigation and ascorbic acid treatment interactions, the highest number of seeds per head (1121.9) and grain yield (9.13 ton/ha) was allocated to level of 100ppm ascorbic acid under normal irrigation condition. Among the interactions of salicylic acid and ascorbic acid treatment the highest value of  seeds number of head (1091.6), grain yield (9.98 ton/ha) and oil yield (4.58%), was recorded in seeds priming with 200ppm salicylic and 100ppm ascorbic acid. Therefore, to achieve maximum economic yield in both conditions, seeds priming with salicylic acid and ascorbic acid was recommended.