مقایسه اثر تغذیه برگی آمینوکلات گلیسین-روی، فنیل آلانین-روی و Zn-EDTAبر برخی شاخص‌های رشدی و فیزیولوژیکی گل همیشه بهار (Calendula officinalis L.)

The marigold plant (Calendula officinalis L.) is a valuable medicinal plant with numerous medicinal, health, and industrial applications, as well as being used as an ornamental plant. In the present study, the efficiency of foliar nutrition with artificial chelated zinc source and various complexes of amino acid-zinc on the growth and physiological characteristics of the marigold plant were evaluated. This experiment was conducted using completely randomized block design with 7 treatments and 3 replications. The foliar application treatments were: Zn-EDTA, glycine-zinc (Zn-Gly) and phenylalanine-zinc (Zn-Phe) at concentrations of 0, 20 and 40 mg/L. The treatments were done at two stages, the first at the stage of 4-6 leaves and the second before the beginning of flowering. The results indicated that the highest plant height, number of lateral branches, number of flowers, fresh and dry weight of flowers, thousand seed weight, photosynthetic pigments, total carotenoids in the petals, total phenols and flavonoids amount, PAL activity, leaf zinc content, and seed oil percentage were observed at the concentration of 40 mg/L of Zn-Gly treatment which showed a significant difference compared to Zn-EDTA treatment and the control. On the other hand, the present data showed that different treatments did not have any significant difference on the flower diameter. Additionally, the Zn-Gly treatment at both concentrations of 20 and 40 mg/L led a reduction in the number of days to flowering compared to other treatments. The current data indicated that there is a positive and significant correlation (P<0.01) between physiological parameters in different treatments.