Abstract: A pot experiment of Se uptake by two spring soybean cultivars with different Se affinities and using two soils with different Se levels was conducted. The Se translocation and transformation in plant organs was studied after harvest. In soils with high Se level, there was no significant difference in Se accumulation in grains between the two cultivars. However, a stronger Se translocation and accumulation, and higher ratio of organic Se to inorganic Se in grains were found in the cultivars of higher Se affinity than that of low Se affinity although Se translocation in grains was significantly lower in the soils with low Se level. This study indicates that both genotypic and soil affect Se translocation and organic Se synthesis by soybean cultivars, and also shows that difference in organic synthesis under different soil Se level. Higher Se bio-availability in soybean grains can be expected from exotic Se amendments. These may be fundamental for high-Se soybean production and processing for Se nutrition regulation both for animals and human.

Key words: Soybean, Soil Se, Translocation and transformation, Se speciation, Genotypic effect