Effect of foliar application of α-tocopherol and pyridoxine on vegetative growth, flowering, and some biochemical constituents of <i>Calendula officinalis</i> L. plants

Abstract

A field experiment was conducted during 2010 at the Experimental Farm of Fajr, SB University of Kerman, Iran. The aim was to study the effects of foliar spray of α-tocopherol (0, 50, 100 part per million (ppm)) and pyridoxine (0, 50, 100 ppm) on vegetative growth, flowering parameters, and some chemical constituents of Calendula officinalis L. plants. Most parameters were significantly affected by application of two vitamins which were used in this study. The obtained results could be summarized as follows; pyridoxine at 100 ppm recorded the best value of leaf area, stem height, chlorophyll b, reducing sugars and hyperoside content; no significant difference was found between plants treated with vitamins in terms of chlorophyll a, root length, fresh weight and dry weight of root; the treatment with α-tocopherol at 100 ppm resulted in the highest yield of seed, fresh and dry aerial parts, as compared to control plants; maximum values of carotenoid were obtained by the application of pyridoxine at 50 ppm; and application of both vitamins led to the reduction of flower diameter.

Keyswords: Calendula officinalis L., α-tocopherol, pyridoxine