Alternative electron sinks in chloroplasts and mitochondria of halophytes as a safety valve for controlling ROS production during salinity.

Electron flow through the electron transport chain (ETC) is essential for oxidative phosphorylation in mitochondria and photosynthesis in chloroplasts. Electron fluxes depend on environmental parameters, e.g.

Melatonin mediated tolerance to benzalkonium chloride phytotoxicity through improved growth, photochemical reactions, and antioxidant system in wild-type and snat2 mutant Arabidopsis lines.

Melatonin (Mel) is a phytohormone that plays a crucial role in various plant processes, including stress response. Despite numerous studies on the role of Mel in stress resistance, its significance in plants exposed to benzalkonium chloride (BAC) pollution remains unexplored. BAC, a common antiseptic, poses a threat to terrestrial plants due to its widespread use and inefficient removal, leading to elevated concentrations in the environment.

Role of Abscisic Acid, Reactive Oxygen Species, and Ca Signaling in Hydrotropism-Drought Avoidance-Associated Response of Roots.

Plant roots exert hydrotropism in response to moisture gradients to avoid drought stress. The regulatory mechanism underlying hydrotropism involves novel regulators such as MIZ1 and GNOM/MIZ2 as well as abscisic acid (ABA), reactive oxygen species (ROS), and Ca signaling. ABA, ROS, and Ca signaling are also involved in plant responses to drought stress.

Differential regulation of reactive oxygen species in dimorphic chloroplasts of single cell C plant during drought and salt stress.

Single cell C (SCC) plants, discovered around two decades ago, are promising materials for efforts for genetic engineering of C photosynthesis into C crops. Unlike C plants with Kranz anatomy, they exhibit a fully functional C photosynthesis in just a single cell and do not require mesophyll and bundle sheath cell spatial separation. is one such SCC plant, with NAD-malic enzyme (NAD-ME) subtype C photosynthesis.

Nanomaterial sulfonated graphene oxide advances the tolerance against nitrate and ammonium toxicity by regulating chloroplastic redox balance, photochemistry of photosystems and antioxidant capacity in Triticum aestivum.

The current study was designed to assess nanomaterial sulfonated graphene oxide (SGO) potential in improving tolerance of wheat chloroplasts against nitrate (NS) and ammonium (AS) toxicity. Triticum aestivum cv. Ekiz was grown under SGOs (50-250-500 mg L) with/without 140 mM NS and 5 mM AS stress.

Pretreatment of seeds with hydrogen peroxide improves deep-sowing tolerance of wheat seedlings.

Drought is a prevalent natural factor limiting crop production in arid regions across the world. To overcome this limitation, seeds are sown much deeper to boost germination by soil moisture produced by underground water. Seed pretreatment can effectively induce deep-sowing tolerance in plants.

Differential responses of the scavenging systems for reactive oxygen species (ROS) and reactive carbonyl species (RCS) to UV-B irradiation in Arabidopsis thaliana and its high altitude perennial relative Arabis alpina.

The present work aimed to compare antioxidant response and lipid peroxide detoxification capacity of an arctic-alpine species Arabis alpina to its close relative model species Arabidopsis thaliana under acute short duration (3 h and 6 h) UV-B stress (4.6 and 8.2 W/m).

Day and Night Fluctuations in GABA Biosynthesis Contribute to Drought Responses in L.

When synchronized with the light/dark cycle the circadian rhythm is termed a diurnal rhythm and this organizes an organism's daily life cycle in relation to the metabolic shifts during the day/night cycles. This is a complex task, particularly under stress conditions. Accurate maintenance of the diurnal rhythm becomes an issue under environmental extremes, such as drought due to the impairment of metabolism, redox balance, and structural integrity.

Melatonin mitigates UV-B stress via regulating oxidative stress response, cellular redox and alternative electron sinks in Arabidopsis thaliana.

Melatonin plays an active role in neutralizing free radicals, especially by triggering the defense system and certain enzymes that work under stress in both mammals and plant systems. Exposure to ultraviolet (UV-B) stress can be deadly for plants since UV-B can induce production of reactive oxygen species and damage nucleic acids. In the present study, to uncover the possible alleviative role of melatonin against UV-B stress, Arabidopsis thaliana plants were treated with melatonin (10 μM) and were exposed to UV-B stress for 90 min and 180 min (46 and 92 kJ m d).

Naringenin induces tolerance to salt/osmotic stress through the regulation of nitrogen metabolism, cellular redox and ROS scavenging capacity in bean plants.

The present study was conducted to uncover underlying possible effect mechanisms of flavonoid naringenin (Nar, 0.1-0.4 mM) in nitrogen assimilation, antioxidant response, redox status and the expression of NLP7 and DREB2A, on salt (100 mM NaCl) and osmotic-stressed (10% Polyethylene glycol, -0.

The involvement of gamma-aminobutyric acid shunt in the endoplasmic reticulum stress response of Arabidopsis thaliana.

The endoplasmic reticulum (ER) is the main site of secretory protein production and folding and its homeostasis under environmental stress is vital for the maintenance of the protein secretory pathway. The loss of homeostasis and accumulation of unfolded proteins in the ER is referred to as ER stress. Although, γ-aminobutyric acid (GABA) is an important regulator of stress response in plants, its roles during ER stress remains unclear.

Flavonoid Naringenin Alleviates Short-Term Osmotic and Salinity Stresses Through Regulating Photosynthetic Machinery and Chloroplastic Antioxidant Metabolism in .

The current study was conducted to demonstrate the possible roles of exogenously applied flavonoid naringenin (Nar) on the efficiency of PSII photochemistry and the responses of chloroplastic antioxidant of salt and osmotic-stressed (. For this aim, plants were grown in a hydroponic culture and were treated with Nar (0.1 mM and 0.

Hydrogen sulfide (HS) and nitric oxide (NO) alleviate cobalt toxicity in wheat (Triticum aestivum L.) by modulating photosynthesis, chloroplastic redox and antioxidant capacity.

The role of hydrogen sulfide (HS)/nitric oxide (NO) in mitigating stress-induced damages has gained interest in the past few years. However, the protective mechanism HS and/or NO has towards the chloroplast system through the regulation of redox status and activation of antioxidant capacity in cobalt-treated wheat remain largely unanswered. Triticum aestivum L.

Opportunities and Limitations of Crop Phenotyping in Southern European Countries.

The Mediterranean climate is characterized by hot dry summers and frequent droughts. Mediterranean crops are frequently subjected to high evapotranspiration demands, soil water deficits, high temperatures, and photo-oxidative stress. These conditions will become more severe due to global warming which poses major challenges to the sustainability of the agricultural sector in Mediterranean countries.

Understanding the Role of the Antioxidant System and the Tetrapyrrole Cycle in Iron Deficiency Chlorosis.

Iron deficiency chlorosis (IDC) is an abiotic stress often experienced by soybean, owing to the low solubility of iron in alkaline soils. Here, soybean lines with contrasting Fe efficiencies were analyzed to test the hypothesis that the Fe efficiency trait is linked to antioxidative stress signaling via proper management of tissue Fe accumulation and transport, which in turn influences the regulation of heme and non heme containing enzymes involved in Fe uptake and ROS scavenging. Inefficient plants displayed higher oxidative stress and lower ferric reductase activity, whereas root and leaf catalase activity were nine-fold and three-fold higher, respectively.

Reactive oxygen species and redox regulation in mesophyll and bundle sheath cells of C4 plants.

Redox regulation, antioxidant defence, and reactive oxygen species (ROS) signalling are critical in performing and tuning metabolic activities. However, our concepts have mostly been developed for C3 plants since Arabidopsis thaliana has been the major model for research. Efforts to convert C3 plants to C4 to increase yield (such as IRRI's C4 Rice Project) entail a better understanding of these processes in C4 plants.

Interplay between the unfolded protein response and reactive oxygen species: a dynamic duo.

Secretory proteins undergo modifications such as glycosylation and disulphide bond formation before proper folding, and move to their final destination via the endomembrane system. Accumulation of unfolded proteins in the endoplasmic reticulum (ER) due to suboptimal environmental conditions triggers a response called the unfolded protein response (UPR), which induces a set of genes that elevate protein folding capacity in the ER. This review aims to establish a connection among ER stress, UPR, and reactive oxygen species (ROS), which remains an unexplored topic in plants.

Endoplasmic reticulum stress regulates glutathione metabolism and activities of glutathione related enzymes in Arabidopsis.

Stress conditions generate an extra load on protein folding machinery in the endoplasmic reticulum (ER) and if the ER cannot overcome this load, unfolded proteins accumulate in the ER lumen, causing ER stress. ER lumen localised protein disulfide isomerase (PDI) catalyses the generation of disulfide bonds in conjugation with ER oxidoreductase1 (ERO1) during protein folding. Mismatched disulfide bonds are reduced by the conversion of GSH to GSSG.

Mg deficiency changes the isoenzyme pattern of reactive oxygen species-related enzymes and regulates NADPH-oxidase-mediated ROS signaling in cotton.

The aim of this work was to investigate changes in isoenzyme patterns of enzymes related to reactive oxygen species (ROS) detoxification such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductase (GR), and glutathione-S-transferase (GST) in cotton under Mg deficiency. Moreover, we aimed to elucidate how a ROS producer, NADPH oxidase (NOX), responds to changing Mg levels. Cotton plants were grown with different concentrations of MgSO 4 in hydroponic medium to create nutrient deficiency (0, 75, 150, 1000 µM Mg).

Changes in redox regulation during transition from C to single cell C photosynthesis in Bienertia sinuspersici.

Bienertia sinuspersici performs single cell C photosynthesis without Kranz anatomy. Peripheral and central cytoplasmic compartments in a single chlorenchyma cell act as mesophyll cells and bundle sheath cells. Development of this specialized mechanism is gradual during plant development.