Diagnosis of copper deficiency in wheat by plant analysis

Abstract

A glasshouse experiment was conducted to define critical concentrations of copper in young leaves of wheat and to investigate the effect of water stress after anthesis on the relationship between yield and copper concentrations in young leaves. The concentration of copper in the youngest fully emerged leaf was a sensitive and accurate indicator of the copper status of wheat. The critical concentration for copper in the youngest fully emerged leaf did not change with the age of the plant. Copper deficiency occurred whenever the concentration of copper in the youngest fully emerged leaf fell below 1.3 �g g-I (dry weight). Water stress after anthesis did not change the relationship between copper concentrations in young leaves and grain yield, although this stress markedly decreased grain yield. In the field there was considerable variability among plants given the same copper treatment in copper concentrations in young leaves. Nevertheless, whenever copper deficiency decreased growth, the average concentration of copper in the youngest fully emerged leaf was less than 1.3 �g g-1.