Effect of saffron (Crocus sativus L.) corm provenance on its agro-morphological traits and bioactive compounds

A three-year field study was conducted to examine the variation in agronomic performance, apo-carotenoids content, bioactive compounds and antioxidant activity of saffron corms originating from nine different regions of Iran. Significant differences were observed in flower-related traits, corm characteristics, picrocrocin and safranal contents, total phenolic content (TPC), total flavonoid content (TFC) and radical-scavenging activity between saffron corms of different provenance. The largest differences were observed for the flower-related traits and corm properties. Hierarchical classification of the saffron corms of different provenance resulted in three main groups. One of the three groups (provenance: Ferdows, Sarayan, and Bajestan) had high underground and above ground yield potential and also produced significantly higher picrocrocin and TFC in comparison to the other groups. In contrary the group comprising corms from Zarand, Torbat, Natanz, and Estahban were characterized by the lowest agronomic performance, TFC as well as lowest antioxidant activity. The third group, consisting of corms from Gonabad and Qaen, represented medium levels of agronomic-related traits, and the highest TPC and antioxidant ability. These results were further explored and confirmed by principal component analysis (PCA). PCA revealed positive relationships between corm properties on the one hand and flower number and stigma yield on the other hand. No relation between agronomic related traits and quality features was observed. Furthermore, the results indicated a positive relationship between total flavonoid content and antioxidant capacity of saffron. These results can be used for the improvement of the yield and quality as well as in programs for selection of the most suitable corms for particular production locations.