Soybean cadmium concentration: validation of a QTL affecting seed cadmium accumulation for improved food safety

Abstract

Soybean can accumulate considerable amounts of cadmium depending on soil conditions. As low cadmium concentration of soybean is of great interest in soy food production, a major quantitative trait locus described earlier for controlling cadmium accumulation in the seed was utilized to classify early maturity genotypes with respect to cadmium uptake and to verify their cadmium accumulation level. Marker-selected soybean genotypes were then tested for cadmium accumulation in a pot experiment with three cadmium levels and at three field locations in Austria. Out of 48 soybean genotypes, 19 exhibited the microsatellite marker allele associated with low cadmium accumulation. In the pot experiment, seed cadmium concentration was below 0.15 mg kg -1 in low cadmium accumulating genotypes while it reached over 0.30 mg kg -1 in genotypes carrying the high cadmium allele. In field experiments, cadmium concentration was in the range between 0.03 and 0.16 mg kg -1 , and both the cadmium accumulation locus as well as the experimental locations had a significant influence on seed cadmium. Marker-assisted selection of soybean genotypes for low cadmium accumulation could thus contribute to improved food safety which is particularly important for environments with unknown cadmium status of soil.

Genetic Control of Cadmium Concentration in Soybean Seeds

“…The SSR analysis identified soybean cultivars with potential health risk when grown in metal-polluted areas, regardless of their natural tolerance [59]. Vollmann et al [60] validated the low seed Cd accumulation trait based on the Cda1 locus and the associated Sack149 marker. Out of 48 genotypes evaluated, 19 exhibited the allele associated with low and 29 with high Cd accumulation in the seed.…”

Development of soybeans with low P34 allergen protein concentration for reduced allergenicity of soy foods

“…Nevertheless, stacking of low‐P34 and other food safety characters is highly relevant for improving the value of soybean protein. In the present study, both parent genotypes share a low cadmium accumulation trait in addition to segregation in P34, which gives a similar stack of desirable traits to soybean breeding and for the subsequent development of soybean products with improved food safety.…”

“…Nucleotide sequences of primer pairs were utilized from previously published SSR loci . Soybean DNA extraction as well as amplification and evaluation of PCR products has been described elsewhere . A linkage analysis between SSR markers was carried out using the MAPMAKER/EXP 3.0 program…”

Cadmium concentrations in German soybeans are elevated in conurbations and in regions dominated by mining and the metal industry

“…Recently, the observed large differences in the accumulation of the toxic compound in different cultivars have resulted in the identification of presumably Cd‐safe soybean genotypes . Heavy metal‐related isozymes and genes may be addressed in future breeding programs aiming to reduce the Cd uptake of modern cultivars …”