6 research outputs found
Salicylic Acid Priming Improves Cotton Seedling Heat Tolerance through Photosynthetic Pigment Preservation, Enhanced Antioxidant Activity, and Osmoprotectant Levels
No full textThe escalating global temperatures associated with climate change are detrimental to plant growth and development, leading to significant reductions in crop yields worldwide. Our research demonstrates that salicylic acid (SA), a phytohormone known for its growth-promoting properties, is crucial in enhancing heat tolerance in cotton (Gossypium hirsutum). This enhancement is achieved through modifications in various biochemical, physiological, and growth parameters. Under heat stress, cotton plants typically show significant growth disturbances, including leaf wilting, stunted growth, and reduced biomass. However, priming cotton plants with 1 mM SA significantly mitigated these adverse effects, evidenced by increases in shoot dry mass, leaf-water content, and chlorophyll concentrations in the heat-stressed plants. Heat stress also prompted an increase in hydrogen peroxide levels—a key reactive oxygen species—resulting in heightened electrolyte leakage and elevated malondialdehyde concentrations, which indicate severe impacts on cellular membrane integrity and oxidative stress. Remarkably, SA treatment significantly reduced these oxidative stresses by enhancing the activities of critical antioxidant enzymes, such as catalase, glutathione S-transferase, and ascorbate peroxidase. Additionally, the elevated levels of total soluble sugars in SA-treated plants enhanced osmotic regulation under heat stress. Overall, our findings reveal that SA-triggered protective mechanisms not only preserve photosynthetic pigments but also ameliorate oxidative stress and boost plant resilience in the face of elevated temperatures. In conclusion, the application of 1 mM SA is highly effective in enhancing heat tolerance in cotton and is recommended for field trials before being commercially used to improve crop resilience under increasing global temperatures
Ethanol Treatment Enhances Physiological and Biochemical Responses to Mitigate Saline Toxicity in Soybean
No full textSoil salinity, a major environmental concern, significantly reduces plant growth and production all around the world. Finding solutions to reduce the salinity impacts on plants is critical for global food security. In recent years, the priming of plants with organic chemicals has shown to be a viable approach for the alleviation of salinity effects in plants. The current study examined the effects of exogenous ethanol in triggering salinity acclimatization responses in soybean by investigating growth responses, and numerous physiological and biochemical features. Foliar ethanol application to saline water-treated soybean plants resulted in an enhancement of biomass, leaf area, photosynthetic pigment contents, net photosynthetic rate, shoot relative water content, water use efficiency, and K+ and Mg2+ contents, leading to improved growth performance under salinity. Salt stress significantly enhanced the contents of reactive oxygen species (ROS), malondialdehyde, and electrolyte leakage in the leaves, suggesting salt-induced oxidative stress and membrane damage in soybean plants. In contrast, ethanol treatment of salt-treated soybean plants boosted ROS-detoxification mechanisms by enhancing the activities of antioxidant enzymes, including peroxidase, ascorbate peroxidase, catalase, and glutathione S-transferase. Ethanol application also augmented the levels of proline and total free amino acids in salt-exposed plants, implying a role of ethanol in maintaining osmotic adjustment in response to salt stress. Notably, exogenous ethanol decreased Na+ uptake while increasing K+ and Mg2+ uptake and their partitioning to leaves and roots in salt-stressed plants. Overall, our findings reveal the protective roles of ethanol against salinity in soybean and suggest that the use of this cost-effective and easily accessible ethanol in salinity mitigation could be an effective approach to increase soybean production in salt-affected areas
Ethanol-mediated cold stress tolerance in sorghum seedlings through photosynthetic adaptation, antioxidant defense, and osmoprotectant enhancement
No full textSorghum (Sorghum bicolor L.), an often overlooked but vital staple crop, suffers severe obstacles in growth and yield due to temperature fluctuations, especially low temperatures. Therefore, scientists nowadays pay impulsive attention to overcoming the deleterious consequences of cold stress (CS) in sorghum. Our current investigations revealed that the application of ethanol (0.2 %) to the root zone of sorghum plants enhanced biomass production, improved gas-exchange features and the levels of photosynthetic pigments, and enhanced leaf relative water content, which collectively contributed to a significant enhancement in the growth performance of sorghum seedlings when subjected to CS conditions (8 °C). Exposure to CS leads to a substantial buildup of reactive oxygen species (ROS), notably hydrogen peroxide, along with elevated levels of malondialdehyde and electrolyte leakage in sorghum leaves, unequivocally indicating the occurrence of oxidative stress in sorghum seedlings. In contrast, the addition of 0.2 % ethanol demonstrated a remarkable ability to alleviate the oxidative burden caused by ROS by substantially enhancing the activities of key antioxidant enzymes, including catalase, peroxidase, glutathione S-transferase and ascorbate peroxidase, and the level of total flavonoids, within the leaves of sorghum seedlings subjected to CS. Furthermore, ethanol treatment exhibited additional benefits by increasing the levels of total soluble sugars and total free amino acids in sorghum seedlings, which are likely to play a pivotal role in maintaining osmotic balance in response to CS. In conclusion, our findings highlight the defensive mechanism modulated by ethanol in promoting the adaptation mechanisms of sorghum seedlings for abatement of cold-induced damage
Green vanguards: Harnessing the power of plant antioxidants, signal catalysts, and genetic engineering to combat reactive oxygen species under multiple abiotic stresses
No full text© 2024The resilience of plants to concurrent abiotic stresses—such as drought, salinity, extreme temperatures, heavy metals, and elevated CO2 levels—is paramount in the era of climate change. Reactive oxygen species (ROS), traditionally perceived as mere byproducts of metabolic processes, serve a dual role: as crucial signaling molecules that facilitate plant adaptation and as deleterious agents causing cellular damage when excessively accumulated. In this review, we highlighted the intricate equilibrium that plants maintain through both enzymatic and non-enzymatic antioxidant defenses to mitigate ROS-mediated oxidative stress, emphasizing the sophisticated strategies plants deploy to counteract a spectrum of combined abiotic stresses. Some plant species, however, exhibit insufficient enhancement of their intrinsic antioxidant defenses to counterbalance stress-induced ROS accumulation and consequent oxidative damage. Consequently, we explored the pivotal role of diverse signaling molecules in further strengthening antioxidant defenses, offering profound insights into bolstering plant resilience. Furthermore, the advent of genetic engineering technologies unveils novel avenues for crop improvement, with the strategic overexpression of antioxidant genes such as SOD, APX, CAT, GPX, DHAR, GR, and GST showing immense potential in fortifying plants against oxidative challenges imposed by multiple abiotic stresses. Future perspectives entail deepening our understanding of the molecular mechanisms governing ROS generation and scavenging, investigating the synergistic effects of co-expressing antioxidant genes, and elucidating the interactions between endogenous plant hormones and exogenously applied signaling molecules. We advocate for integrative research methodologies, combining field experiments, controlled environmental studies, and computational modeling, to bridge the gap between laboratory discoveries and practical agricultural applications
Zn Supplementation Mitigates Drought Effects on Cotton by Improving Photosynthetic Performance and Antioxidant Defense Mechanisms
No full textDrought is recognized as a paramount threat to sustainable agricultural productivity. This threat has grown more severe in the age of global climate change. As a result, finding a long-term solution to increase plants’ tolerance to drought stress has been a key research focus. Applications of chemicals such as zinc (Zn) may provide a simpler, less time-consuming, and effective technique for boosting the plant’s resilience to drought. The present study gathers persuasive evidence on the potential roles of zinc sulphate (ZnSO4·7H2O; 1.0 g Kg−1 soil) and zinc oxide (ZnO; 1.0 g Kg−1 soil) in promoting tolerance of cotton plants exposed to drought at the first square stage, by exploring various physiological, morphological, and biochemical features. Soil supplementation of ZnSO4 or ZnO to cotton plants improved their shoot biomass, root dry weight, leaf area, photosynthetic performance, and water-use efficiency under drought stress. Zn application further reduced the drought-induced accumulations of H2O2 and malondialdehyde, and electrolyte leakage in stressed plants. Antioxidant assays revealed that Zn supplements, particularly ZnSO4, reduced reactive oxygen species (ROS) accumulation by increasing the activities of a range of ROS quenchers, such as catalase, ascorbate peroxidase, glutathione S-transferase, and guaiacol peroxidase, to protect the plants against ROS-induced oxidative damage during drought stress. Increased leaf relative water contents along with increased water-soluble protein contents may indicate the role of Zn in improving the plant’s water status under water-deficient conditions. The results of the current study also suggested that, in general, ZnSO4 supplementation more effectively increased cotton drought tolerance than ZnO supplementation, thereby suggesting ZnSO4 as a potential chemical to curtail drought-induced detrimental effects in water-limited soil conditions
Biochar potentially enhances maize tolerance to arsenic toxicity by improving physiological and biochemical responses to excessive arsenate
No full text© 2023, The Author(s). cc-byMetalloid pollution, including arsenic poisoning, is a serious environmental issue, plaguing plant productivity and quality of life worldwide. Biochar, a carbon-rich material, has been known to alleviate the negative effects of environmental pollutants on plants. However, the specific role of biochar in mitigating arsenic stress in maize remains relatively unexplored. Here, we elucidated the functions of biochar in improving maize growth under the elevated level of sodium arsenate (Na2AsO4, AsV). Maize plants were grown in pot-soils amended with two doses of biochar (2.5% (B1) and 5.0% (B2) biochar Kg−1 of soil) for 5 days, followed by exposure to Na2AsO4 ('B1 + AsV'and 'B2 + AsV') for 9 days. Maize plants exposed to AsV only accumulated substantial amount of arsenic in both roots and leaves, triggering severe phytotoxic effects, including stunted growth, leaf-yellowing, chlorosis, reduced photosynthesis, and nutritional imbalance, when compared with control plants. Contrariwise, biochar addition improved the phenotype and growth of AsV-stressed maize plants by reducing root-to-leaf AsV translocation (by 46.56 and 57.46% in ‘B1 + AsV’ and ‘B2 + AsV’ plants), improving gas-exchange attributes, and elevating chlorophylls and mineral levels beyond AsV-stressed plants. Biochar pretreatment also substantially counteracted AsV-induced oxidative stress by lowering reactive oxygen species accumulation, lipoxygenase activity, malondialdehyde level, and electrolyte leakage. Less oxidative stress in ‘B1 + AsV’ and ‘B2 + AsV’ plants likely supported by a strong antioxidant system powered by biochar-mediated increased activities of superoxide dismutase (by 25.12 and 46.55%), catalase (51.78 and 82.82%), and glutathione S-transferase (61.48 and 153.83%), and improved flavonoid levels (41.48 and 75.37%, respectively). Furthermore, increased levels of soluble sugars and free amino acids also correlated with improved leaf relative water content, suggesting a better osmotic acclimatization mechanism in biochar-pretreated AsV-exposed plants. Overall, our findings provided mechanistic insight into how biochar facilitates maize’s active recovery from AsV-stress, implying that biochar application may be a viable technique for mitigating negative effects of arsenic in maize, and perhaps, in other important cereal crops. Graphical Abstract: [Figure not available: see fulltext.
