Variation in morphological characters, chemical composition, and anthocyanin content of different Chrysanthemum morifolium cultivars from Iran

The morphological traits, essential oil composition, and anthocyanin content of 17 Iranian C. morifolium cultivars were evaluated. Based on Shannon diversity index (I), such morphological characters as flower head diameter, ray floret, shape of apex, and main color of ray floret revealed more variability than the other traits. Significant genotypic variations were also observed in essential oil content (ranging from 0.1 to 0.56% (w/w)) and composition. Gas chromatography-mass spectrometry (GC-MS) analysis of the essential oil was conducted to identify 47 compounds in which camphor (0-44.6%), chrysanthenone (0-48.96%), chrysanthenyl acetate (0-16.22%), verbenol (0-11.78%), (+)-5-epi-neointermedeol (0-25.41%), and aromadendrene (0-14.98%) were the main constituents. Results of cluster analysis of essential oil compositions divided the cultivars into four groups. Hybridization among cultivars of divergent clusters led to heterotic effects for flower quality and phytochemical characters. The relationships established between the components revealed high correlations of anthocyanin with the two major aroma compounds of verbenol and chrysanthenyl acetate while they also provided a clue to the association between aroma compounds and color pigmentation. Moreover, a correlation was established between chrysanthenone and flower head diameter (r = −0.502). Based on the results obtained, it might be suggested that smaller flowers are capable of accumulating higher amounts of chrysanthenone. Clearly, the associations between morphological traits and essential oil components provide new insights for improved breeding programs in chrysanthemum.