The enhanced root system of cytokinin-deficient transgenic plants and its consequences for mineral uptake

摘要

The formation of an enhanced root system was achieved in transgenic plants by the expression of a single dominant gene, CKX, which codes for a cytokinin degrading enzyme. Thus this trait, which is difficult to assess by classical methods, cam now be manipulated in a targeted fashion. Further work was carried out with plants exhibiting repressed cytokinin signaling because of receptor mutations. An enhanced root system may improve access to water and minerals, which are often limiting factors for plant growth in agricultural ecosystems. On soils contaminated with trace elements, plants with an enhanced root system may be more effective in soil cleanup (phytoremediation). We have determined the uptake of soil minerals and Cd by transgenic cytokinin-deficient tobacco plants and compared it to control plants. Results of these experiments will be reported.