Relationship of Flower Color Parameters and Metal Ions of Petal Tissue in Fully Opened Flowers of Gerbera

Interaction of pigments and metal ions can change the final color of the petals. Metal ions can affect stability of flowers final color by altering vacuolar pH and activity of enzymes involved in biosynthesis, destruction, accumulation and transition of pigments. In this study, amounts of metal ions of petal tissue and their relationships with parameters of petal color analyzed and compared in stage of full blooming in six varieties Gerbera with different colors. Investigation on metal ions in different varieties statistically did not show significant differences in Cu2+ amounts. Results showed that increase Fe2+ amount in petals increase redness (a* value) and Chroma (C*) and decrease lightness (L * value). Also, decrease Zn2+ amount in petal tissue increase color hue (h * value). Exactly, the opposite of calcium (Ca2+), Magnesium (Mg2+) showed a significant and positive difference with parameters of C * and a*, also a significant and negative correlation observed between Mg2+ amount and L * value. Generally, in this study among evaluated metal ions in different varieties of Gerbera, ions of Fe2+, Ca2+ and Mg2+ presented more effective relationship with flower color parameters. Also, range of amounts of Fe2+, Cu2+, Zn2+, Mn2+, Ca2+ and Mg2+ limited to 0.0076-0.012, 0.0035-0.004, 0.0017-0.003, 0.0021-0.0032, 2.18-2.97 and 1.45-1.79 mg g-1 fresh weight, respectively