Cadium Enhanced Copper Absorption Via Down Regulate Abscisis Acid Level in Nicotiana Benthamiana.

Metal absorption efficiency is of concern in the application of phytoremediation. Most of the pollutant sites were contaminated with multiple heavy metals. In this study, the mixture of cadmium (Cd) and copper (Cu) was processed to illustrate the responses of plant under the mixture of heavy metals. Six-week-old tobacco plants were subject to various heavy metal treatments and to the analysis of metal contents, water status and plant hormone abscisic acid (ABA) contents. The results showed the Cd absorption was not affected by the coexisting of Cu. However, the Cu absorption was enhanced by the coexisting of Cd. The regression analyses showed that the enhancement of Cu absorption under the coexisting of Cd was correlated with the decrease of water content and also with the decrease of ABA content. The results of floating tobacco disc on heavy metals solution showed that the ABA content was increased by Cu treatment, but decreased by Cd treatment suggesting that the elevated ABA that induced by Cu in the tobacco plants might interrupted by Cd application. Thus, it was concluded that the metal absorption efficiency under multiple heavy metals contaminated sites could be influenced by ABA levels of plant in responding to different heavy metals species in soil.