Editorial: Heavy metal toxicity in plants: Recent insights on physiological and molecular aspects, volume II

Abstract

Heavy metal toxicity in plants: Recent insights on physiological and molecular aspects, volume II Metals with relatively high densities, atomic numbers, or atomic weights are regarded as heavy metals. Among them, some metals are considered essential nutrients (Fe, Co, Zn), or relatively harmless (Ru, Hg, In). However, they can be toxic in higher amounts. At higher levels, heavy metals have abilities to create severe toxic symptoms in crop plants, and therefore, their utilization and uptake are greatly controlled by the plant cells. It has been reported that both essential and non-essential metals produce common toxic symptoms on crop plants, such as chlorosis, low biomass accumulation, photosynthesis, inhibition of growth, and nutrient assimilation that ultimately cause plant death. To combat metal stress, plants have evolved different defense modifications viz., less uptake of metals, phytochelatins binding, and the activation of numerous antioxidants. The first strategy to combat heavy metals in plants is to activate their enzymatic (POD, SOD, APX, CAT, GR) and non-enzymatic (ASA, GSH) antioxidants. The second strategy is to activate their root exudates and cell wall. The third strategy is to utilize plants (phytoremediation) which can absorb the metal content from the soil at higher rates. Lastly, exogenous applications of growth regulators, nutrients, and organic amendments such as ALA, GABA, MeJA, AsA, NPs, MLE, and Se provide some kind of relief to crop plants to combat the hazardous effects of HMs. In a summary, all the amendments under metal/metalloid stress can help the plants to strengthen their defense mechanism and improve their growth in a metal toxic environment. Our Research Topic mainly focuses on plant abnormalities, like alteration in PG&D, nutrient unbalances, and enzyme dysfunctioning due the metal/metalloid toxicity.

Topics & Concepts