Investigation of genetic variation for yield and morphological traits in Silybum marianum L. genotypes

This investigation was carried out on 14 populations of Silybum marianum which were collected from different regions of Iran. The experiment was conducted as a randomized complete block design with 3 replications at Isfahan Agriculture Research Center. Results of analysis of variance showed significant differences for all of the studied traits (p<0. 01). There were considerable genotypic coefficient of variation for grain yield، total capitulum weight per plant and single capitulum weight. Correlation coefficients showed significant positive correlation between grain yield and total capitulum weight per plant. Principal components analysis revealed that، the first two PCA components comprised about 76% of the total variation. Ward cluster analysis grouped the populations in 4 groups. The least Euclidean distance was observed between the populations 5 and 6. The highest Euclidean distance occurred between populations 1 and 4. The results also showed high genetic potential among the Iranian Silybum marianum populations. This feature is used in breeding programs such as crossing and producing synthetic cultivars with desirable agronomic characteristics.