Abstract:

Soil contamination by heavy metals has become one of the most serious environmental problems in the world. Trees have deep roots, produce abundant biomass, generally do not enter the human food chain, and several species revealed the capacity to tolerate and accumulate heavy metals, created a barrier to prevent the spread of heavy metal pollution. In order to thoroughly explore the resistance mechanism of trees to heavy metal pollution, the author reviewed the advances on the mechanisms of heavy metal resistance in trees, including the following aspects: root exudates, endophytic bacteria and mychorrhizas, metal chelation, antioxidant system and compartmentalization in recent years. Heavy metal brought about multidimensional impact on trees and the resistance mechanisms of trees was complexity. Hence, more in-depth research was needed in the future. At last, the prospects of exploitation of trees for remediation through biotechnology tools were provided.