Iron application ameliorates copper toxicity effects in spinach

Influence of copper toxicity was discernible in 25 days old plants of spinach (Spinacea oleracea L.) cv. Banarasi after twenty days of induction of high Cu at 100 μM grown in refined sand with complete nutrient solution. Excess Cu decreased the biomass, concentration ofiron, chlorophyll and activity of catalase in spinach leaves with an acretion in the activity of peroxidase and polyphenol oxidase and leaf Cu. Besides this, there was decrease in growth and plants developed interveinal chlorosis in old leaves. These adverse effects were alleviated to variable extent either by withholding excess Cu supply or by supplementation ofiron as Fe-EDTA at double concentration (200 μM) or by spraying Fe as Fe-EDT A/FeSO₄, (200 μM)five times on alternate days. Fe-EDTA was more effective than FeSO₄ in resuming the shoot growth, whereas concentration of Fe, chlorophyll and catalase activity in leaves were recovered more effectively by spray of FeSO₄.