Copper (Cu) is one of the most important essential trace elements
for plant normal growth and development. However, excessive
soluble Cu in soil is highly toxic to plants and often results in
vegetation degradation and soil quality decrease (e.g. nutrient
deficiency and microbial activity decline), thus negatively affecting
ecosystem functioning . Also,
Cu contaminated soils pose high risk to human health as Cu might
enter food chain via agricultural products and drinking water .
Widespread Cu contamination usually results
from industrial and agricultural activities such as mining, smelting,
sewage irrigation, pesticide and fertilizer application .
For the reclamation of contaminated land, excessive Cu must
be removed from the soil. Traditional treatments like physical and
chemical approaches are either labor intensive, low cost effective or
environmental unfriendly . In contrast, phytoremediation,
the use of plants and associated microbes to treat or
stabilize contaminated soils, sediments, or groundwater, is low cost
and environmentally sustainable