Phyto-Chemical and Morphological Characters of Calendula officinalis as Affected by Micronutrients

In order to study the effect of foliar applications of micronutrients on yield, extraction oil production and chemical composition of pot marigold (Calendula officinalis), two experiments were conducted in the randomized complete block design with three replications in Shahrekord, Iran during two growing seasons 2014 and 2015. The objectives of this study were to determine the effects of foliar Fe2+, Cu2+, Zn2+, and Mn2+ applications (0, 200 and 400 ppm) on flavonoid, phenols, carotenoids, extraction percentage, dry weight of the flower and the number of flowers of pot marigold. Results showed that foliar applications of Fe2+, Cu2+, Zn2+, and Mn2+ had significant effects on fresh and dry flower yield, number of flowers, extraction oil percentage and flavonoids, phenols, carotenoids of pot marigold plants, so that the highest dry weight of flowers (11.9 g per plant), number of flowers per plant (33.5), extraction oil percentage (1) and flavonoids (31.2 mg/ 100 g F.W.), phenols (56.2 mg/ 100 g F.W.) and carotenoids (0.8 mg/ 100 g F.W.) content were obtained from the application of a combination of Fe2+, Cu2+, Zn2+, and Mn2+ at 400 ppm concentration as compared to control in the second year. It seems that in climatic and edaphic conditions of Shahrekord, the best treatments for obtaining the highest extraction percentage and morphological characters of Calendula is 400 ppm of Fe, Zn, Cu and Mn.