Variation for some important agronomic traits in 100 spring safflower (Carthamus tinctorius L.) genotypes.

3 Abstract: The present study was aimed to examine different agronomic traits in 100 safflower genotypes. The experimental design was a 10 x 10 simple lattice. The results of analysis of variance demonstrated that the differences among genotypes were highly significant (P<0.01) for all studied traits. Phenotypic and genotypic correlations showed that the grain yield per plant is significantly correlated with grain yield per plot, biomass, number of capitula, 100 - seed weight, number of secondary branches and oil yield per plant. There was also a positive correlation between kernel% and oil content, therefore selection for high oil content can be based on thin-hull seeds. High values of phenotypic and genotypic coefficients of variation were obtained for most traits, indicating high variability in the traits under study. Phenotypic coefficients of variation (PCV) ranged from 3.3% in days to maturity to 42% in ineffective capitula and genotypic coefficients of variation (GCV) ranged from 3.65% in days to bud formation to 35.7% in oil yield. The recorded data were subjected to principal component analysis. The results showed that seven principal components with eigen values more than one explained 80.7% of the total variability. The genotypes were classified in four groups: A, B, C and D for safflower breeding goals (high grain and oil yield, short growth duration) based on PC1 and PC2 (as the most important principal components).