Purpose Agronomic practices are one of the reasons for the increasing accumulation of elements in the soil, including manganese (Mn). Our previous studies have shown that selenium (Se) ions can reduce the toxic actions of metal stress. Those, we studied the effects of Mn—treated as a stressor and Se – as a potential defense in plants. Methods Mn ions (10 mM) or/and Se (15 μM) were added into hydroponic nutrients of two wheat cultivares. The evaluation of the stress-generating and protective actions were analyzed by biochemical methods and microscopic observations in leaves and roots. Moreover the level of DNA methylation for these tissues was determined. Results Mn application caused an increase of lipid peroxidation and hydrogen peroxide content in both leaves and roots and was accompanied with a greater absorption of this element by the roots. For other elements (K, Fe, S, P), with the exception of Ca, the reduced their uptake was registered, especially in roots. For roots, Mn stimulated greater, microscopically observed, desorganization in cell structure as compared to leaves, which was accompanied by a quantitative increase in 5-methylcytosine (5-metC) in root meristem. Se application diminished the effects of Mn-stress. Conclusions These studies is the first in which indicated that global 5-metC level in roots enhancing from dividing meristematic cells to elongating cells of the axial cylinder and cortex. It was suggested that the rise in Ca level can lead to modification of root cells differentiations what may be one of the steps in defense mechanisms.
Purpose Due to its physiological importance as a micronutrient, manganese supplementation requires taking into account the possibility of overdosing, which is associated with the initiation of stressogenic effects in plant cells. The use of nanoparticles may reduce the amount of Mn ion administered, especially during foliar treatment. Hence, the aim of the research was to demonstrate the mechanism of action of MnNPs on plant cells and to determine the extent of the stress-inducing reaction of these NPs. Methods A response to manganese nanoparticles was studied in seedlings of two wheat cultivars, model system of plant cell membranes and compared with cell lines (U-937, HL-60, HUT-78, COLO-720L). The nanoparticles (MnNPs as Mn3O4) were at the same concentrations (125 and 250 mg/mL) by foliar application to plants and to the cell culture media. Results The administration of NPs enhanced the content of Mn in plant cells, indicating its penetration through the leaf surface and initiated the oxidative stress measures as an increase in enzyme activity, starch accumulation, and a decrease in chlorophyll synthesis. Moreover, a rise in the electrokinetic potential of the chloroplast membrane surface and the reconstruction of their hydrophobic parts toward an increase in fatty acid saturation was found. Conclusion The study demonstrated that the stress response in plant cells was initiated up to 250 mg/mL of MnNPs. The same concentration resulted in reduction of cell viability, especially in U-937 line.
Industrial and agronomic activities lead to oversupply and accumulation of elements in the environment. Relatively little is known about mechanisms of manganese (Mn) triggered stress. In this study, different cultivars of popular cereals wheat, oat, and barley were investigated for their response to excessive Mn. Manganese ions (MnCl2) at 5 and 10 mM were applied to the grains and then to the media on which the plants grew until they developed their first leaf. It was performed ICP MS aiming to understand the mechanism of manganese stress in susceptible and resistant cultivar. Under Mn-stress a decrease in fresh weight of plants was observed, also differences in water content in first leaves, an increase in superoxide dismutases (SOD) and peroxidases (POX) activity, and a significant rise in catalase (CAT) was only characteristic for barley. Increasing Mn concentration resulted in enhancing of manganese superoxide dismutase (Mn-SOD) and copper, zinc superoxide dismutase (Cu/Zn-SOD) bands intensity. The increase in proline content, depending on a balance between pyrroline-5-carboxylate synthase (P5CS), ornithine-d-aminotransferase (OAT), and proline dehydrogenases (PHD) activities, indicated osmotic disorders in all plants and differentiated the studied cereals. Microscopic observations of changes in the structure of plastids and starch accumulation in Mn presence were particularly visible in sensitive cultivars. The study ranked the tested cereals in terms of their tolerance to Mn from the most tolerant wheat through barley and the least tolerant oats.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.