Plant Adaptation to Recalcitrant Chemicals

The massive growth of urbanization, agriculture, and other anthropogenic activities has created serious environmental pollution with the use of numerous recalcitrant chemicals. Various polycyclic aromatic hydrocarbons, aromatic hydrocarbons, nitroaromatic compounds, polychlorinated biphenyls, dioxins, and their derivatives are greatly toxic, mutagenic, and carcinogenic to natural microflora as well as to humans. In the biodegradation of toxic organic compounds, xenobiotics, and heavy metals, hyperaccumulating plants and plant-associated bacteria (including endophytic bacteria and rhizospheric bacteria) have enormous potential to improve phytoremediation. In particular, endophytic and rhizospheric bacteria may break down recalcitrant chemicals in polluted soil. Approaches from toxicology, stress physiology, and ecotoxicology will be helpful for the characterization of plant responses to recalcitrant chemicals. Therefore, it is necessary to understand plants’ adaptation strategies against various harmful recalcitrant chemicals.