Saline irrigation water management strategies for better yield of safflower (Carthamus tinctorius L.) in an arid region

Water quality and irrigation strategies are important factors effecting crop production, especially in arid/saline soils. The effects of irrigation water salinity and irrigation management on safflower yield was studied in a field experiment in Isfahan province (central Iran). Three irrigation water salinity levels of 3.4, 8.8 and 11.2 dS m -1 , two irrigation water managements and two leaching levels of without leaching and with leaching levels of 6, 17, and 28.5 %, were used in a completely randomized block design, arranged as Split-Split plots with four replications for each treatment. The results showed that with higher levels of water salinity the yield components such as seed yield, biomass yield (dry weight), number of plant per hectare, 1000- seed weight, plant height, number of capitula per plant and capitula weight per plant were significantly decreased. Although, irrigation with high amount of salt in water (11.2 dS m -1 ) during the entire growth period reduced the yield, irrigating with water salinity of 3.4 dS m -1 , until plant emergence and then applying high irrigation water salinity levels significantly increased the yield components. Leaching application caused a significant increase in the yield and yield components, too. The salinity threshold value of 6.4 dS m -1 was obtained for safflower seed