Distribution of Pb in Different Parts of Wheat Grains and Its Relationship with Other 8 Elements

By environmental scanning electron microscopy and X-ray electron probe microanalysis, the relative content of Pb was studied in the cortex, the aleuronic layer, the scutellum, the plumule, the hypocotyl, the radicle and the endosperm of wheat grains with different genotypes. The results showed that the Pb content differred as follows: aleuronic layer > hypocotyl > radicle > scutellum > plumule > cortex > endosperm. There were genetic differences in Pb enrichment among genotypes of wheat grains, reflected by the differences of Pb content in the same part of wheat greains as well as in different parts. There were significant linear correlations between the Pb content in aleuronic layer, hypocotyl, radicle, scutellum, plumule, cortex, endosperm of wheat grains. The results also showed that there were extremely significant linear correlations between the Pb content and that of Cd, Al, Mg, Si, P, K, Ca, S respectively in the seven parts of wheat grains with different genotypes.