Heavy metal detoxification and tolerance mechanisms in plants: Implications for phytoremediation

Abstract

30Heavy metals such as cobalt, copper, manganese, molybdenum, and zinc are essential in trace 31 amounts for growth by plants and other living organisms. However, in excessive amounts these 32 heavy metals have deleterious effects. Like other organisms, plants possess a variety of 33 detoxification mechanisms to counter the harmful effects of heavy metals. These include, the 34 restriction of heavy metals by mycorrhizal association, binding with plant cell wall and root 35 excretions, metal efflux from the plasma membrane, metal chelation by phytochelatins and 36 metallothioneins, and compartmentalization within the vacuole. Phytoremediation is an emerging 37 technology which uses plants and their associated rhizospheric microorganisms to remove 38 pollutants from contaminated sites. This technology is inexpensive, efficient and ecofriendly. 39 This review focuses on potential cellular and molecular adaptations by plants that are necessary 40 to tolerate heavy metal stress.41 42

Role of Acinetobacter sp. CS9 in Improving Growth and Phytoremediation Potential of Catharanthus longifolius under Cadmium Stress

“…During the present study, higher contents of Cd were observed in roots as compared to aerial parts of C. longifolius plants under Cd stress. The cadmium may be absorbed in roots through symplastic or apoplastic pathways [52]. Similar to our findings, higher Cd contents were observed in roots of tall fescue and bluegrass plants subjected to Cd stress [53].…”

IDENTIFICATION OF ANTIOXIDANTS IN ALCHORNEA CORDIFOLIA (SCHUMACH. & THONN.)MÜLL. ARG, A CANDIDATE PLANT FOR PHYTOREMEDIATION OF POLLUTED SOILS WITH MANGANESE.

“…Conversely, increasing the pH causes immobilization by formation of insoluble compounds or increased anion exchange capacity (Gleyzes et al, 2002). The pH variations therefore have complex and sometimes opposite consequences on the mobility of heavy metals, particularly in the presence of organic and inorganic ligands (Kushwaha et al, 2016). It is a fundamental element in controlled nutrition, because it determines assimilation conditions of mineral elements.…”

Designing Heap Leaching for Nickel Production that Environmentally and Economically Sustain

“…Bamboo stakes are used to prevent laterite from aglomerating due to sulfuric acid leach. Bamboo can be planted around the industrial area and can be used as a phytoremediation plant [13]. In general heap leaching using PVC plastic instead of bamboo that is difficult to degrade.…”