The effects of copper and nitrogen supply on the distribution of copper in dissected wheat grains

Abstract

The distribution of copper between the embryo and the endosperm was studied in the grain of two wheat cultivars (Gamenya and Petit Rojo) grown at marginal and sufficient copper and two levels of nitrogen.

Copper concentration in whole grain increased markedly with copper level but differed little with nitrogen level. The dry weight and copper content of the embryo expressed as a proportion of the whole grain varied little among treatments, so that copper concentration in the embryo responded to treatment in a similar way to copper concentration in the whole grain. Copper concentrations in the embryo were at least 2.5 times as high as in the endosperm or whole grain at all levels of copper and nitrogen.

It is suggested that where copper deficiency decreases grain number without decreasing the weight of individual grains the copper concentration in the mature whole grain, or in the embryo, is not causally related to grain development, and may be a poor indicator of the potential response of grain yield to copper application.