The effect of soil pH on copper toxicity to forage maize grown under field conditions.

Cu toxicity to forage maize was studied in a factorial field experiment comprising 4 Cu rates (0, 100, 200 or 300 kg Cu/ha) and 4 pH levels. Results are presented for crop yield and mineral composition. Raising the soil pH reduced the toxic effect of Cu to a smaller extent than would be predicted from the reduction in the Cu2+ ion activity. Apparently an increase in pH increased the toxicity of Cu2+ ions in sol. (Abstract retrieved from CAB Abstracts by CABI’s permission)