抄録
Cadmium (Cd) is a widely used metal in industry; however it is extremely toxic even at low concentrations. Rice grains contaminated with Cd represent a major risk to the health of more than half of the world population who depends on rice as basic source of energy.
We have targeted the development of rice plants that contain low amounts of Cd in grains using transgenic techniques. A rice T-DNA library was constructed and then screened for the Cd tolerant phenotype resulting in selection of low Cd (lcd) mutant.
In lcd plants, the T-DNA is inserted in the first intron of the LCD gene located in the chromosome 1. LCD expression localized mainly in the vascular bundle in roots, and in phloem companion cells in shoots, suggesting a relationship between LCD and Cd transport. LCD is specific for rice and no reports have been found about its function up to date.
Growth on experimental field in Korea on a Cd contaminated soil showed that lcd grains had a 55% reduction in Cd content when compared to WT. No differences in grain yield, grain weight, grain appearance, tiller number and leaf blade DW were observed. This is a promising line to mitigate the threat of Cd to human health.
