Plants face a myriad of environmental obstacles as they grow and develop, both in natural and cultivated environments. Drought, among other challenges, is indisputably one of the most urgent factors that can significantly affect plant productivity. Water is a vital element that contributes to many physiochemical processes in plants, such as growth, development, and metabolism. This is because 75-95% of a plant's fresh biomass is comprised of water, underscoring the importance of plant productivity (Brodersen et al., 2019). Therefore, drought is regarded as a primary environmental stressor for various plants (Diatta et al., 2020), especially in arid regions, and is regarded as the foremost significant global threat to food security, having triggered major famines in the past (Okorie et al., 2019). The effects of drought on farming are exacerbated by the exhaustion of water resources and the increasing demand for food, fueled by the alarming growth of the global population (O’Connell, 2017). The variability of drought occurrence is influenced by multiple factors, such as inconsistent and erratic precipitation patterns, evapotranspiration rates, and the water retention capacity of the rhizosphere (DeVincentis, 2020). In certain instances, plants may experience physiological drought, also referred to as pseudo-drought (Salehi-Lisar and Bakhshayeshan-Agdam, 2020), wherein they are incapable of taking in water from the soil, despite the presence of adequate moistness (Daryanto et al., 2017). In addition, drought stress exposure has a negative impact on various morpho-physiological, biochemical, and molecular characteristics, as well as the ecological processes of plants (Ortiz et al., 2015). Furthermore, water-deficient conditions negatively impact plant yield and quality (Battaglia et al., 2018). The way in which plants respond to drought is correlated with numerous aspects including plant species, growth stages, age, as well as the duration and severity of the drought (Gray and Brady, 2016). The mechanisms through which plants adapt to drought conditions vary among species. Consequently, plants can adapt their resource allocation and alter their growth behavior to effectively respond to the challenging environmental conditions caused by drought (Bielach et al., 2017). Numerous molecular networks, such as those associated with signal transduction, play an important role in enhancing the capability of crops to respond to drought stress (Zandalinas et al., 2020). According to a study, the application of ZnO.NPs increased the expression of Fe/Mn-SOD, Cu/Zn SOD, APX, CAT, WRKY, ERD and DREB genes in plants, resulting in improved tolerance against drought stress (Huang et al., 2012, Kandhol et al., 2022, Sun et al., 2020). Apart from molecular aspects underlying plant reaction to drought stress, plants also utilize stomatal regulation via augmented ion transportation, root acclimation, osmotic adjustments, and regulation of antioxidant enzymes (Kumar et al., 2019, Prakash et al., 2019).
As environmental challenges continue to escalate, melon (Cucumis melo L.) crops are becoming increasingly vulnerable to drought stress, highlighting the urgent need for innovative and sustainable approaches, such as the integration of nanoparticle technology. At present, the use of agrochemicals in agriculture is estimated to be 0.04 billion tons. However, this is projected to double by 2050 to support the food requirements of 9.5 billion individuals (Kah et al., 2019). It is crucial to adopt techniques that enable more efficient use of natural resources to achieve agricultural sustainability. In recent times, the utilization of nanotechnology has been on the rise in diverse fields, including agriculture. Nanoparticles (NPs) have the potential to serve as sources of micronutrients, providing plants with nutritional benefits and enhancing their tolerance against different types of stress (Raliya et al., 2015). Green synthesis is a relatively new area of nanobiotechnology that involves synthesizing nanoparticles using plant-based materials. Green synthesis is a simpler, cheaper, and more reproducible process that results in stable nanoparticles with minimal toxicity compared to other methods (Azmat et al., 2022). NPs have demonstrated the capacity to enhance plant growth when used at appropriate concentrations, in addition to their well-established role in biomedical applications (Khan et al., 2019). Zinc oxide nanoparticles (ZnO.NPs) have been found to play a significant role in enhancing plant growth and productivity, although higher concentrations can be toxic to plants (Zulfiqar et al., 2019). The incorporation of ZnO.NPs in plant growth and productivity can be attributed to the provision of essential zinc nutrients, which help adjust plant response mechanisms including, photosynthetic pigments production, cell elongation, expression of genes, and the upregulation of antioxidant enzymes (Yuvaraj and Subramanian, 2020). Number of researches have corroborated the constructive influence of ZnO.NPs on plant development, especially in unfavorable environmental conditions including drought. The incorporation of ZnO.NPs have been found to augment the antioxidant activity and relative water content in rice and soybean species, resulting in increased tolerance to drought stress conditions (Sedghi et al., 2013, Upadhyaya et al., 2020). There is limited understanding of the potential of ZnO.NPs synthesized from Artemisia annua bio-extract in mitigating drought stress, despite the positive influence of different metallic NPs on plant growth under various biotic and abiotic stresses. Therefore, the present research aims to investigate the potential use of green synthesized ZnO.NPs in enhancing C. melo crop response to drought stress, including stimulation of antioxidant enzymes activity and drought related marker genes, as well as the uptake of essential nutrients and photosynthetic functions.
Fresh leaves of Artemisia annua and zinc sulphate heptahydrate (ZnSO4·7H2O) were acquired from the School of Agriculture and Biology, Shanghai Jiao Tong University, China. A. annua, commonly known as sweet wormwood, is a plant with significant medicinal properties, including, antibacterial, anti-inflammatory and antioxidant properties (Gomathi and Suhana, 2021, Wang et al., 2020a). Plant leaves were thoroughly cleaned with de-ionized water and kept to dry at ambient temperature. Desiccated
ZnO.NPs alleviate morphological alterations
The morphological parameters of melon seedlings were significantly affected by drought stress in DS treatment in comparison with the control (Table 2). The shoot length (SL), stem diameter (SD), leaf area (LA), Fv/Fm, shoot fresh and dry weight declined by approximately 23, 13, 14, 33, 77 and 45%, respectively, relative to the control. However, the treatment of ZnO.NPs significantly mitigated the deleterious impact of drought stress on shoot morphological attributes. Nonetheless, this effect
Plants encounter various abiotic stresses, but drought stress stands out as one of the most detrimental environmental challenges, obstructing numerous physiological and biochemical aspects, crucial for plant growth and productivity (Ashraf, 2010). To cope with fluctuating environmental conditions including drought, plants have evolved to develop a diverse set of defense responses including ROS scavenging mechanism through stimulating antioxidant enzymes and drought associated genes, stomatal
The present research illustrated that ZnO.NPs treatment improved the drought tolerance capability of C. melo seedlings along with improvement in nutrients uptake and vegetative growth. ZnO.NPs dosage momentously stimulated the upregulation of antioxidant enzymatic activities and gene expression which in turn reduced the oxidative damage and protected the ultrastructural integrity of the chloroplast. Furthermore, ZnO.NPs supplementation marked a significant improvement in photosynthetic
CRediT authorship contribution statement
Asad Rehman: Conceptualization, Experimentation, Writing – original draft, Writing – review & editing. Jinyang Weng and Pengli Li: Methodology, Software, Writing – review & editing. Iftikhar Hussain Shah and Saeed ur Rahman: Conceptualization, Investigation, Writing – review & editing. Muhammad Khalid: Software, Writing – review & editing. Muhammad Aamir Manzoor: Visualization, Writing – review & editing. Liying Chang: Supervision, Software, Writing – review & editing. Qingliang Niu:
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
This work was supported by Shanghai Melon and Watermelon Industry Technical System, China (2017-2021).
Identification and expression analysis of sugar transporter family genes reveal the role of ZmSTP2 and ZmSTP20 in maize disease resistance
Journal of Integrative Agriculture, 2022
Sugar is an indispensable source of energy for plant growth and development, and it requires the participation of sugar transporter proteins (STPs) for crossing the hydrophobic barrier in plants. Here, we systematically identified the genes encoding sugar transporters in the genome of maize (Zea mays L.), analyzed their expression patterns under different conditions, and determined their functions in disease resistance. The results showed that the mazie sugar transporter family contained 24 members, all of which were predicted to be distributed on the cell membrane and had a highly conserved transmembrane transport domain. The tissue-specific expression of the maize sugar transporter genes was analyzed, and the expression level of these genes was found to be significantly different in different tissues. The analysis of biotic and abiotic stress data showed that the expression levels of the sugar transporter genes changed significantly under different stress factors. The expression levels of ZmSTP2 and ZmSTP20 continued to increase following Fusarium graminearum infection. By performing disease resistance analysis of zmstp2 and zmstp20 mutants, we found that after inoculation with Cochliobolus carbonum, Setosphaeria turcica, Cochliobolus heterostrophus, and F. graminearum, the lesion area of the mutants was significantly higher than that of the wild-type B73 plant. In this study, the genes encoding sugar transporters in maize were systematically identified and analyzed at the whole genome level. The expression patterns of the sugar transporter encoding genes in different tissues of maize and under biotic and abiotic stresses were revealed, which laid an important theoretical foundation for further elucidation of their functions.
Hydrogen sulfide alleviates salt stress through auxin signaling in Arabidopsis
Environmental and Experimental Botany, Volume 211, 2023, Article 105354
Hydrogen sulfide (H2S) is a third gas transmitter following nitric oxide and carbon monoxide, that regulates plant growth, photosynthesis, and responses to abiotic stress. Auxin, a crucial plant hormone, is widely involved in stress response and plant growth processes. H2S and auxin interact with each other to regulate root growth. Whether H2S functions in the auxin signaling pathway under salt stress remains unclear. In this study, we used the double mutant of the H2S-producing enzyme-encoding gene L-cysteine desulfhydrase (lcd des1), which found that H2S was involved in alleviating salt stress through auxin signaling in Arabidopsis using physiological and transcriptomic data. RNA-seq analysis identified 267 differentially expressed genes (DEGs) in response to salt stress and revealed that H2S activated salt-related genes and limited cellular activities associated with growth through the regulation of auxin signaling. Furthermore, auxin transport-related mutants (pin347, aux1–7) and auxin signal transduction related mutants (tir1–1, arf10 16) had a significantly inhibited root length under salt stress, and root growth inhibition were alleviated after exogenous H2S treatment. Exogenous H2S treatment, however, did not alleviate inhibition in pin2 with salt treatment. Taken together, these findings suggest that H2S regulates Arabidopsis salt tolerance and inhibits root growth by regulating PIN2 expression.
Neutronic response of the neutral beam after EAST NBI upgraded
Fusion Engineering and Design, Volume 192, 2023, Article 113806
In order to improve the heating effect of neutral beam injector, the neutral beam injector (NBI) of the Experimental Advanced Superconducting Tokamak (EAST) is planned to be upgraded. After the EAST NBI is upgraded, the neutron emission intensity will increase. Neutron leaking from the neutral beam port penetrate the beamline, resulting in the material radiation damage. The neutronic response has been investigated by using the Monte Carlo particle transport code MCNP with the two dimensional RZ model of the EAST NBI. The results demonstrate that a 40% increase of the neutron emission rate has been attained with the upgraded EAST NBI. However, the simulations for the activation of different materials, displacement damage and nuclear heating of the neutral beam still satisfy the requirement of material safety performance. The calculations of nuclear response show that the materials can meet the requirements of the NBI steady state operation after the EAST NBI updated.
Arsenic (As) resistant bacteria with multiple plant growth-promoting traits: Potential to alleviate As toxicity and accumulation in rice
Microbiological Research, Volume 272, 2023, Article 127391
A currently serious agronomic concern for paddy soils is arsenic (As) contamination. Paddy soils are mostly utilized for rice cultivation. Arsenite (As(III)) is prevalent in paddy soils, and its high mobility and toxicity make As uptake by rice substantially greater than that by other food crops. Globally, interest has increased towards using As-resistant plant growth-promoting bacteria (PGPB) to improve plant metal tolerance, promote plant growth, and immobilize As to prevent its uptake and accumulation in the edible parts of rice as much as possible. This review focuses on the As-resistant PGPB characteristics influencing rice growth and the mechanisms by which they function to alleviate As toxicity stress in rice plants. Several recent examples of mechanisms responsible for decreasing the availability of As to rice and coping with As stresses facilitated by the PGPB with multiple PGP traits (e.g., phosphate and silicate solubilization, the production of 1-aminocyclopropane-1-carboxylate deaminase, phytohormones, and siderophore, N2 fixation, sulfate reduction, the biosorption, bioaccumulation, methylation, and volatilization of As, and arsenite oxidation) are also reviewed. In addition, future research needs about the application of As-resistant PGPB with PGP traits to mitigate As accumulation in rice plants are described.
Transcriptome analysis of fiber development under high-temperature stress in flax (Linum usitatissimum L.)
Industrial Crops and Products, Volume 195, 2023, Article 116019
In recent years, frequent extreme climates (including high temperatures) have increasingly threatened the production of crops. Flax is a crop suitable for growing in a cool environment, and its fiber formation is greatly affected by temperature. However, the understanding of the regulatory effect of high-temperature (HT) stress on fiber development at the RNA level is limited. In this study, we selected three developmental stages of flax fiber (fiber elongation stage, fiber cell thickening stage, and fiber maturity stage), combined with second-generation and 3rd-generation transcriptome sequencing, to explore how HT (30 ℃) stress affects the development of flax fiber at the molecular level. The number of differentially expressed genes (DEGs) of the bast in the fiber elongation stage, fiber cell thickening stage, and fiber maturity stage were 2889, 3131, and 5244, respectively. In these three stages, HT had different effects on the development of fiber cells. Through Weight gene co-expression network analysis (WGCNA) and gene co-expression network analysis, hub gene Lus10007349 (XTH) involved in the process of fiber cell expansion and cell wall thickening, and it was sensitive to HT stress and serves as a candidate gene for subsequent research. In addition, we found that under HT stress, the number of fiber cells, cell wall thickness, phloem thickness, and fiber cell area decreased. Determined the chemical composition of the final harvested fiber under HT stress, in which the content of cellulose and acid-soluble lignin was reduced, and the content of pectin was increased. The results of a large number of DEGs sequencing will broaden our understanding of the complex molecular and cellular events in the development of flax phloem fibers affected by HT stress, and lay the foundation for the improvement of flax fibers in the future.
Curcumin-ZnO nanocomposite mediated inhibition of Pseudomonas aeruginosa biofilm and its mechanism of action
Journal of Drug Delivery Science and Technology, Volume 81, 2023, Article 104301
Multidrug-resistance and strong biofilm formation potential of P. aeruginosa makes it a severe risk to public health and nanoparticles/nanocomposites find potential applicability to address this crisis. Curcumin is a potential anti-biofilm/antibacterial molecule that is limited due to large sized particle, reduced water solubility and decreased bioavailability. In this study, curcumin-ZnO nanocomposite was synthesized and its anti-biofilm efficacy as well as mechanism of action against P. aeruginosa biofilm was investigated. Here, using the FTIR peaks, the novel structure of curcumin-ZnO nanocomposites was established and using that as ligand the potential anti-biofilm drug targets were identified followed by superoxide anion, lipid peroxidation, cell viability and TEM analysis to reveal its mechanism of anti-biofilm action. Here, curcumin-ZnO nanocomposites at 300μg/mL dosage having suitable particle size (110.51nm), improved zeta potential (−22.3mV), reduced hydrodynamic size (253.2nm) were more efficiently able to penetrate through biofilm matrix and bind to P. aeruginosa's cell membrane through the OprM-MexAB receptor and inhibit its growth and biofilm (efficacy=49.36% compared to control) than ZnO nanoparticle (42.38% compared to control). Curcumin-ZnO nanocomposites could efficiently inhibit P. aeruginosa biofilm by mechanisms involving increased superoxide anion generation by 48.94% possibly due to catalase and rubredoxin-rubredoxin reductase inhibition that mediated increased bacterial membrane lipid peroxidation by 183.75% thus causing severe disintegration of cell membrane and increased cell death by 25.18% compared to control. Curcumin-ZnO nanocomposites can thus be considered as a capable anti-biofilm drug candidate against P. aeruginosa infections.
© 2023 Elsevier B.V. All rights reserved.
Zinc oxide (ZnO) nanoparticles (NPs) have been synthesized using Hibiscus subdariffa leaf extract. Temperature dependent synthesis and particle growth have been studied. Formation of NPs was confirmed by UV-visible (UV-VIS) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD).What is the role of zinc oxide nanoparticles in mediating abiotic stress responses in plant? ›
ZnO NPs stimulate the formation of phytohormones, osmolytes, antioxidant enzymes, and metabolites in plants against abiotic stress, revealing the promising role of ZnO NPs in combating the stress. However, ZnO NPs must be used in plants appropriately to obtain the benefits.How are zinc oxide nanoparticles made? ›
First, the reaction between zinc acetate dihydrate and DEG/TEG leads to esterification that forms (Zn-OH)2. Further dehydration of (Zn-OH)2 results into formation of ZnO nanoparticles.What is the advantage of green synthesis of nanoparticles? ›
Green synthesis is more beneficial than traditional chemical synthesis because it costs less, decreases pollution, and improves environmental and human health safety.What is the effect of zinc oxide nanoparticles on plant growth? ›
ZnO NPs promote onion growth and reduce the flowering period at 20 and 30 mg/L concentrations (Laware and Raskar, 2014). Burman et al. (2013) reported an improved growth in the chickpea with foliar application of Zn, whereas Prasad et al. (2012) reported increased root/shoot growth in peanut plant.What is the effect of nanoparticles on drought stress in plants? ›
NPs exhibit alleviating effects against drought stress via induction of physiological and biochemical readjustments accompanied by modulation of gene expression involved in drought response/tolerance. NPs ameliorate drought-induced reduction in carbon assimilation via increasing the photosynthetic activity.What is the role of nanoparticles in drought stress? ›
Nanoparticles (NPs) play a key role in enhancing drought stress (DS) tolerance in plants. NPs reduce MDA accumulation, maintain membrane stability, induce the expression of stress-related proteins, improve nutrient and water uptake, increase photosynthesis, and increase grain yield and harvest index.What is the critical role of zinc in plants facing the drought stress? ›
Moreover, Zn interacts with plant hormones, increases the expression of stress proteins and stimulates the antioxidant enzymes for counteracting drought effects.What are the disadvantages of zinc oxide nanoparticles? ›
However, ZnO has several disadvantages, such as the fast recombination of photogenerated electron-hole pairs, it is only active with UV light, and it suffers from photocorrosion . To solve these limitations, ZnO has been combined with other materials such as metals, semiconductors, and nanocarbons.What is the toxic effect of zinc oxide nanoparticles? ›
Inhalation and instillation of ZnO NPs result in lung inflammation and systemic toxicity. The solubility of ZnO NPs plays an important role in this inflammation.
“Non-nano” and “nano” refer to the size of the particles of zinc oxide. The range for "non-nano" is 100 nanometers (nm) or greater, while "nano" zinc oxide (used because it is non-whitening) is typically 10-20 nm in size. To give you a sense of how small that is, one nanometer is a billionth of a meter.What is green synthesis method for nanoparticles? ›
Green synthesis employs a clean, safe, cost effective and environmentally friendly process of constructing nanomaterials. Microorganisms such as bacteria, yeast, fungi, algal species and certain plants act as substrates for the green synthesis of nanomaterials (Figure 3).What is green chemical approach for nanoparticles? ›
Typically, the green synthesis of nanoparticles has been reported to involve mixing of preferably aqueous extracts with aqueous solution of metal salt. The reduction reaction completes in few minutes to few hours at room temperature.What is green synthesis of nanoparticles using bacteria? ›
Bacteriapossess remarkable ability to reduce heavy metal ions and are one of the best candidates for nanoparticle synthesis. For instance, some bacterial species have developed the ability to resort to specific defense mechanisms to quell stresses like toxicity of heavy metal ions or metals.What is the green synthesis of zinc? ›
angustifolia. During green synthesis of ZnONPs, the colour of the solution mixture of zinc nitrate hexahydrate and E. angustifolia leaf extract changed from light brown to yellowish black in colour. This colour change indicated the reduction of metallic zinc (Zn+) ions to zinc (ZnO) NPs.