Heavy Metal Stress and Some Mechanisms of Plant Defense Response

By A. Emamverdian, Yulong Ding, Farzad Mokhberdoran, Yin-feng Xie. TheScientificWorldJournal, 2015

968 citations recorded by the source corpus.

Unprecedented bioaccumulation and biomagnification of heavy metals (HMs) in the environment have become a dilemma for all living organisms including plants. HMs at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to excessive augmentation of reactive oxygen species (ROS). This would inflict serious morphological, metabolic, and physiological anomalies in plants ranging from chlorosis of shoot to lipid peroxidation and protein degradation. In response, plants are equipped with a repertoire of mechanisms to counteract heavy metal (HM) toxicity. The key elements of these are chelating metals by forming phytochelatins (PCs) or metallothioneins (MTs) metal complex at the intra- and intercellular level, which is followed by the removal of HM ions from sensitive sites or vacuolar sequestration of ligand-metal complex. Nonenzymatically synthesized compounds such as proline (Pro) are able to strengthen metal-detoxification capacity of intracellular antioxidant enzymes. Another important additive component of plant defense system is symbiotic association with arbuscular mycorrhizal (AM) fungi. AM can effectively immobilize HMs and reduce their uptake by host plants via binding metal ions to hyphal cell wall and excreting several extracellular biomolecules. Additionally, AM fungi can enhance activities of antioxidant defense machinery of plants.

Subfields: Plant Science, Pollution

View Paper: https://www.semanticscholar.org/paper/0c1914a30517f2b26e5a736088c27e16483d5b6a

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Plant Science

1. O. Ojuederie
2. M. Rizwan
3. Kamil Kuca
4. Shafaqat Ali
5. N. Dubey
6. Maqshoof Ahmad
7. S. Prasad
8. Swati Singh

In Pollution

1. Vinod Kumar Gupta
2. S. Prasad
3. Shivesh Sharma
4. O. Ojuederie
5. O. Babalola

Citations in the corpus

• Arsenic Uptake, Toxicity, Detoxification, and Speciation in Plants: Physiological, Biochemical, and Molecular Aspects (2018, background): “Similarly, a decrease in chlorophyll biosynthesis in Zea mays [179], Trifolium pratense L.”
• Arbuscular Mycorrhizal Fungi as Potential Agents in Ameliorating Heavy Metal Stress in Plants (2020, background): “High amounts of HMs in plant tissue exert toxicity in plants, disrupt cell membrane permeability, inhibit photosynthesis and mineral uptake, affect plant morpho-physiological and biological processes and ultimately inhibit the growth rate [1,11].”
• Heavy metal remediation and resistance mechanism of Aeromonas, Bacillus, and Pseudomonas: A review (2020, background): “…Old leaves have brown spots and chlorosis Necrosis and leaf shedding Black specks on stems Decreased CO2 absorption but unaffected chlorophyll on plant species Emamverdian et al. (2015); Rao et al. (2016); Reichman (2002) Mn Hgo Hg2þ Affects dark and light reactions Inhibit water channels in…”
• Acquisition and Homeostasis of Iron in Higher Plants and Their Probable Role in Abiotic Stress Tolerance (2018, background): “Some studies suggested that the application of Fe reflects significant and/or potential impacts in alleviating the stress imposed by metal ions (Liu et al., 2007; Yadav et al., 2007; Garnier et al., 2010; Emamverdian et al., 2015).”
• Proline: a key player in plant abiotic stress tolerance (2015, background): “Foliar application of proline under heavy metal stress has shown to be effective method to reduce the toxicity of metals by activating protective mechanisms in plants (Emamverdian et al. 2015).”
• Abiotic Stress Responses and Microbe-Mediated Mitigation in Plants: The Omics Strategies (2017, background): “Various edaphic factors like acidity, salinity, and alkalinity of soils (Bromham et al., 2013; Bui, 2013), pollutant contamination and anthropogenic perturbations (Emamverdian et al., 2015) severely affect plant development and adversely influence crop production (Figure 1).”
• A Review on Practical Application and Potentials of Phytohormone-Producing Plant Growth-Promoting Rhizobacteria for Inducing Heavy Metal Tolerance in Crops (2020, background): “Serious physiological, metabolic, and morphological anomalies thus occur in plants, ranging from chlorosis of leaves, to protein degradation and lipid peroxidation [57].”
• Microbial and Plant-Assisted Bioremediation of Heavy Metal Polluted Environments: A Review (2017, background): “Redox active metals directly generate oxidative stress in plants which disrupt cell homeostasis, affects DNA structure and function, causes damage to the chloroplast and accessory pigments and eventually the cell is destroyed by the production of ROS [137,141,142].”