Effects of Sowing Date and Irrigation Treatment on Safflower Seed Quality

Field experiments were conducted to investigate the effects of sowing dates and irrigation on seed quality of a spring-type safflower cultivar, in karaj-iran, during 2008 and 2009 growing seasons. a split plot design based on a randomized complete block layout with three replications was used in which sowing dates and irrigation treatments comprised the main plot and sub-plot, respectively. the results showed the highest oil yield, oil content, protein yield, and linoleic acid content of safflower seed for sowing date of 19^th of april and under non-water stress conditions. the highest seed protein, oleic acid, and palmitic acid contents were obtained for sowing dates of may 5^th and 20^th along with ceasing irrigation at heading, flowering, and seed filling stages, respectively. under arid and semiarid mediterranean conditions prevailing in karaj, late sowing date led to a greater simultaneity of reproductive stages and higher temperature, which made the negative effect of water stress more prominent than in the early sowing dates.