Lead toxicity in rice: effects, mechanisms, and mitigation strategies—a mini review

Abstract

Lead (Pb) is a major environmental pollutant that affects plant morpho-physiological and biochemical attributes. Its higher levels in the environment are not only toxic to human beings but also harmful for plants and soil microbes. We have reviewed the uptake, translocation, and accumulation mechanisms of Pb and its toxic effects on germination, growth, yield, nutrient relation, photosynthesis, respiration, oxidative damage, and antioxidant defense system of rice. Lead toxicity hampers rice germination, root/shoot length, growth, and final yield. It reduces nutrient uptake through roots, disrupts chloroplastic ultrastructure and cell membrane permeability, induces alterations in leaves respiratory activities, produces reactive oxygen species (ROS), and triggers some enzyme and non-enzymatic antioxidants (as defense to oxidative damage). In the end, biochar amendments and phytoremediation technologies have been proposed as soil remediation approaches for Pb tainted soils.

Improvement of Sorghum Crop through Exogenous Application of Natural Growth-Promoting Substances under a Changing Climate

“…A significant role of applied PGRs (MLE and SWE) in alleviating temperature stress effects in the early stage (15 • C) of the sorghum crop as well as during late vegetative stage (up to 44.6 • C) was possibly attributed towards ROS scavenging activities performed by phenolics and antioxidants present in SWE and MLE [10,47], as overproduction of ROS under abiotic stress affects the plant antioxidant defense system [49]. Improved chlorophyll contents due to MLE application might be the result of maintenance in tissue water relations and improved carbohydrate metabolism [9], due to detoxifying moringa leaf elements.…”

Evaluation of water deficiency impacts on antioxidant enzymes activity and lipid peroxidation in some tomato (Solanum lycopersicum L.) Lines

“…The most deteriorative reactive oxygen species are including oxidant superoxide radical (O 2-), proxyidas, hydroxyl radicals, hydrogen peroxide and single oxygen (Nxele et al, 2017). Plants internal or endogenous enzymes, comprising superoxide dismutase, guaiacol peroxidase as well as catalase and a low-weight molecular network of antioxidants (ascorbate, glutathione, phenolic compounds, tocopherol, carotenoids) formed by enzymatic and non-enzymatic defense systems are potentiate to remove ROS (Ashraf et al, 2015). Peroxidase enzyme importantly contributes in the scavenging of hydrogen peroxide with the aid of ascorbic acid as an electron donor for the reduction of hydrogen peroxide in to water.…”

Cadmium Uptake and Distribution in Fragrant Rice Genotypes and Related Consequences on Yield and Grain Quality Traits

“…The most common visible symptoms of Cd toxicity in growing rice plants include reduction in plant growth and development, chlorosis, and eventually plant death. High Cd accumulation in rice consumed by animals, especially humans, poses several health implications such as cardiac failure, anemia, cancer, hypertension, emphysema, proteinuria, cerebrovascular infarction, damage to the lungs, renal dysfunction in eyes, and osteoporosis [5,6]. Cadmium 2 Journal of Chemistry translocation from soil to roots and shoot and finally to the edible plant parts is often the easiest pathway through which Cd enters the human body [7].…”