The cadmium phytoextraction efficiency of ScMTII gene bearing transgenic tobacco plant

Abstract

Cadmium pollution is a serious world-wide problem affecting the human health and the environmental quality. Phytoremediation, the use of green plants to remove, sequester or detoxify pollutants offers an environmentally-friendly alternative to engineeringbased methods for remediation. The T2 generations of the ScMTII gene bearing transgenic and non-transgenic tobacco plants were grown hydroponically in Hoagland nutrition solution containing 0, 5 and 10 mg/L Cd in controlled growth room to determine their ability to uptake and accumulate Cd within the shoots and roots. There were no significant shoot and root dry weight differences between transgenic and non-transgenic tobacco plants. The ScMTII gene bearing transgenic tobacco plant accumulated 19.8% higher Cd than the non-transgenic tobacco plant in the above ground parts of the plant during the two weeks exposure period in hydroponic culture. In non-transgenic plant, however, Cd is accumulated mainly in the roots. The results of current study indicate that the use of the ScMTII gene bearing transgenic tobacco plant for Cd phytoremediation is limited. Further studies are needed to test the effectiveness of the ScMTII gene for phytoextraction of other heavy metal ions.