Enrichment of Cd in Wheat Grains of Different Genotypes and Its Relationship with Other Eight Elements

Using environmental scanning electron microscopy and X-ray electron probe microanalysis, the Cd relative content was studied in cortex, aleuronic layer, scutellum, plumule, hypocotyl, radicle and endosperm in 20 genotypes of wheat grains. The results showed that the Cd content in different part of 20 genotypes of wheat grains changed as aleuronic layer>hypocotyl>radicle>scutellum>plumule>cortex>endosperm, which reflected the fact the Cd relative content existed mostly in the aleuronic layer. There is genetic difference in the Cd enrichment in different genotypes of wheat grains, reflecting in the difference of Cd relative content in the same part and different part of wheat grains. In different genotypes of wheat grains, there are extremely remarkable linear relations in Cd relative content among the seven parts of wheat grains. The result indicated that the Cd enrichment in the different parts of the 20 genotypes of wheat grains was regulated and controlled by each other, namely, they had the same regulation and control mechanism. It also told us there was difference in the regulation of Cd enrichment among the different parts, which changed linearly in the different genotypes of wheat grains. In addition, there was extremely remarkable linear relations between the content of Cd and those of Al, Pb, Mg, P, S, K, Ca, Si in seven parts of different genotypes of wheat grains.