Ability of some crops for phytoremediation of nickel and zinc heavy metals from contaminated soils

The present study was aimed at comparing the ability of three crop plants for phytoremediation of zinc (Zn) and nickel (Zn) from soils. A factorial (3×2×3) experiment based on RCBD was used to compare the treatments, and was repeated three times. The first factor was crop type (wheat, clover and rapeseed), the second factor was heavy metal types (zinc (Zn) and nickel (Ni)) and the third factor was heavy metal concentration in soil (0.0, 50 and 100 mg.kg-1). With regard to plant type and heavy metal, the highest uptake was recorded in wheat for nickel (Ni) uptake. The lowest uptake of heavy metal was seen in clover crop and nickel (Ni) heavy metal. The highest Ni uptake was observed in wheat at the concentration of 100mg.kg-1. Nickel (Ni) was more absorbed in its higher concentration where the uptake of nickel (Ni) at the concentration of 100.0mg.kg-1 was 182% more than 50.0 mg.kg-1. Generally, the results of this experiment showed that it is possible to use phytoremediation as a suitable means for eliminating the excess concentration of zinc (Zn) and nickel (Ni). In this case, wheat was the superior crop and its mechanisms for removal of heavy metal require further investigation.