Elemental composition of globoid crystals in protein bodies of wheat grain grown on soil treated with sewage sludge

Wheat grain grown on soil treated with a heavy application rate of sewage sludge exhibited higher iron, zinc, copper, and cadmium contents than did wheat grain grown on an unfertilized control treatment. The sludge supplied more than the maximum amounts of zinc, copper, cadmium, and lead recommended for addition to Ontario agricultural lands.Globoid crystals, which are inclusions in protein bodies, are the major mineral storage component of wheat grain. The elemental composition of globoid crystals in wheat grain grown with and without sludge treatment was determined using energy dispersive X-ray (EDX) analysis. Globoid crystals from sludge-treated and control grains exhibited similar elemental compositions with the following exceptions. When comparing sludge-treated grains versus the controls: more globoid crystals in the aleurone layer farthest from the peduncle contained calcium; more coleoptile mesophyll globoid crystals contained calcium, manganese, and (or) iron; some globoid crystals in the young f...