Abstract
To determine the optimum sowing date and plant population for safflower crop (Carthamus tinctorius L.), a factorial experiment was conducted by using randomized completed block design with three replications in AL-Rashidia location about (20 km) west north Nineveh province, Iraq, during the 2008-2009 and 2009-2010 winter growing seasons. Three sowing dates (1st, 3rd October, 4th, 5th November and 2nd,1st December for two seasons 2008-2009 and 2009-2010 respectively) and two plant populations (50000 and 100000 plants.ha-1) were selected. Hartinan, Syrian and Gila cultivars were used. The results showed that the different sowing dates had significant effect on growth characters, yield, yield components and quality, except linoleic acid in 2009-2010 season, the highest mean values were obtained at second sowing date in the two seasons 2008-2009 and 2009-2010. Safflower cultivars significantly differed for all the studied yield, its component and seed quality traits in both seasons, the highest mean values were obtained from Syrian cultivar in both seasons. Seed yield and oil yield influenced by different plant population significantly. Plant population of 50000 plants.ha-1 gave the highest mean for seed oil content and oil yield, while increasing the plant population to 100000 plants.ha-1 caused a significant increase of plant height and palmitic acid percentage in both growing seasons. The result of interaction among sowing dates, cultivars and plant population showed that the highest seed yield was obtained in Syrian cultivar sown in November using plant population of 50000 plants.ha-1. Therefore, Syrian cultivar sown in November with plant population of 50000 plants.ha-1 is recommended for this region.