Study of several important yield correlated agronomic traits in spring safflower varieties via path analysis

In order to determine the relationships among yield and yield components using the correlation coefficients and path analysis. A research was conducted in experimental farm of agricultural faculty of Kerman University during 2005. The experiment was in the form of split plot and randomized complete block design with three replications. The main plot factor was nitrogen (urea) with four levels (0، 50، 75 and 100 kg ha-1) and safflower varieties (landraces belong to Isfahan، Rayen and Kerman and Karaj bred cultivars of IL and PI) were considered as sub plot factor. Results showed that there was a positive correlation (0. 933*) between seed yield and the number of heads per plant. There was also a positive correlation (0. 912*) between the seed yield and the number of secondary branches but there was a negative correlation (-0. 685) between the seed yield and the number of seeds per head. According to path analysis coefficients، the number of heads per plant had the most positive direct effect. Direct effect of plant dry weight on seed yield was negative (-0. 250) and indirect effect of this trait via the number of heads per plant was positive (0. 637). Thus، to obtain the high yield varieties of safflower in breeding programs we can concentrate our aims toward varieties selection with higher number of heads per plant.