Accumulation of Cadmium in Narcissus tazetta L. ornamental plant and its effect on growth character and zinc uptake under In vitro condition

The use of ornamental plants in phytoremediation has attracted a lot of attention due to preventing the entry of heavy metals into the food chain and their beauty in the environment.  Today, tissue culture technique is used as a model system to predict the plants response to environmental pollutants. In the present study to investigate the ability of Narcissus tazetta L. in remediating the environment of cadmium contaminants, in vitro micropropagation of this ornamental plant was done by three procedures: induction, proliferation and bulb production. Then these plantlets were treated by cadmium chloride in three concentrations (1, 2 and 5 mM) in solidified MS culture medium for two weeks. The results showed that Narcissus plantlets are able to accumulate large amounts of cadmium and by increasing cadmium concentration in the medium, its accumulation in plantlets increases; So that in 5 mM treatment, the amount of cadmium in the roots, bulbs and leaves of plantlets was 7502.84, 1971.45 and 398.60 µg g-1DW, respectively. Increasing the concentration of cadmium in the medium caused a decrease in dry weight, amount of pigments, uptake of zinc and peroxidase activity.  In 1 mM cadmium chloride treatment the tolerance index was 0.95 that by increasing cadmium concentration, the tolerance of plantlets decreased. Transfer factor of plantlets were less than one and bioconcentration factor was more than one, indicating that Narcissus can be suggested as a suitable alternative for cadmium contaminant phytostabilization of course requires further research on the soil.