Combined effect of iron and zinc on micronutrient levels in wheat (Triticum aestivum L.).

ABSTRACT

A nutrient solution experiment was conducted to investigate the effect of Fe and Zn supply on Fe, Zn, Cu, and Mn concentrations in wheat plants. The experiment used a factorial combination of two Fe levels (0 and 5 mg l-1) and three Zn levels (0, 0.1 and 10 mg l-1). The supply of Fe (5 mg l-1) and Zn (0.1 mg l-1) increased plant dry weight and leaf chlorophyll content compared to the Fe or Zn deficient (0 mg l-1) treatments. However, excess Zn supply (10 mg l-1) reduced plant dry weights and leaf chlorophyll content. Iron supply (5 mg l-1) reduced wheat Zn concentrations by 49%, Cu concentrations by 34%, and Mn by 56% respectively. Zinc supply (10 mg l-1) reduced wheat Fe concentrations by an average of 8%, but had no significant effect on Cu and Mn concentrations. Stepwise regression analyses indicated that Zn, Cu, and Mn concentrations were negatively correlated with root- and leaf-Fe concentrations, but positively correlated with stem-Fe concentrations. Leaf-Mn concentrations were negatively correlated with root-, stem- and leaf-Zn concentrations.