Effect of sowing date on yield and its components, oil and protein concentration and some agronomical traits of safflower (Carthamus tinctorius. L.)

The purpose of this study was to evaluate the effect of different sowing dates on yield and its components, seeds oil and protein content and some agronomical traits of different safflower cultivars. For these purpose, a study was carried out in Agricultural Research Center of Chaharmahal and Bakhtiari province during 2009-2010. A split-plot design based on randomized complete block with three replications was used. Three sowing dates (21 May, 21 June and 5 July) were assigned in main plots and four genotypes (Zenderood, Goldasht, Isfahan and E2428) were randomized in sub-plots. The results showed that sowing date had very significant effect on yield, seedboll-1, bollplant-1, seed oil and protein content, plant height and branchplant-1.The mean of seed yield at the first, second and third sowing dates were 1466, 622 and 455 kgha-1 respectively. E2428 genotype at the first sowing date (21 May) had the highest seed yield, protein and oil yield, 1000-seed weight, seed boll-1, bollplant-1.Also, seeds yield and oil yield of first (1466 and 367 kg ha-1) and third sowing dates (455 and 56 kg ha-1) was the highest and the lowest respectively. A significant positive correlation was found between oil yield with seed yield and seed boll-1. Based on the results of this study, 21 may was the most suitable sowing date. This study has found that generally in such areas (Semi-humid temperate climate with warm summers and very cold winters) early sowing in early spring will have the most seed and oil yield.