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Introduction: Salicylic acid has shown promise in alleviating water stress in cultivated plants. However, there is a lack of studies confirming its effectiveness in cowpea plants grown in field conditions. Therefore, this research aimed to evaluate the use of salicylic acid as a water stress mitigator in cowpea cultivars under different irrigation depths in field conditions. Methods: Four cowpea cultivars (BRS Novaera, BRS Tapaihum, BRS Pujante, and BRS Pajeu') were subjected to different treatments: control (W100: 100% replacement of crop evapotranspiration - ETc), W50 (50% of ETc), W50+SA2 (50% of ETc + 276 mg L-1 of SA), and W50+SA4 (50% of ETc + 552 mg L-1 of SA). The treatments were combined in a 4×4 factorial scheme with three replications, arranged in a randomized block design. Results: Water restriction had a negative impact on the water status, growth, gas exchange, and production of the cultivars while also leading to changes in the antioxidant metabolism and osmolyte concentration. The application of SA enhanced antioxidant activity and the synthesis of osmotic adjusters under stress conditions. The most effective concentration was 276 mg L-1 in stage R2 and 552 mg L-1 in stage V7, respectively. The BRS Pujante cultivar showed increased productivity under water restriction with SA application, while the BRS Tapaihum was the most tolerant among the cultivars studied. Discussion: In summary, our findings underscore the importance of using SA to mitigate the effects of water restriction on cowpea cultivation. These discoveries are crucial for the sustainability of cowpea production in regions susceptible to drought, which can contribute to food security. We further add that the adoption of new agricultural practices can enhance the resilience and productivity of cowpea as an essential and sustainable food source for vulnerable populations in various parts of the world. [ABSTRACT FROM AUTHOR]

The loss of leaves and needles in tree crowns and tree mortality are increasing worldwide, mostly as a result of more frequent and severe drought stress. Scots pine (Pinus sylvestris L.) is a tree species that is strongly affected by these developments in many regions of Europe and Asia. So far, changes in metabolic pathways and metabolite profiles in needles and roots on the trajectory toward mortality are unknown, although they could contribute to a better understanding of the mortality mechanisms. Therefore, we linked long-term observations of canopy defoliation and tree mortality with the characterization of the primary metabolite profile in needles and fine roots of Scots pines from a forest site in the Swiss Rhone valley. Our results show that Scots pines are able to maintain metabolic homeostasis in needles over a wide range of canopy defoliation levels. However, there is a metabolic tipping point at around 80–85% needle loss. Above this threshold, many stress-related metabolites (particularly osmoprotectants, defense compounds and antioxidants) increase in the needles, whereas they decrease in the fine roots. If this defoliation tipping point is exceeded, the trees are very likely to die within a few years. The different patterns between needles and roots indicate that mainly belowground carbon starvation impairs key functions for tree survival and suggest that this is an important factor explaining the increasing mortality of Scots pines. [ABSTRACT FROM AUTHOR]

IntroductionSalicylic acid has shown promise in alleviating water stress in cultivated plants. However, there is a lack of studies confirming its effectiveness in cowpea plants grown in field conditions. Therefore, this research aimed to evaluate the use of salicylic acid as a water stress mitigator in cowpea cultivars under different irrigation depths in field conditions.MethodsFour cowpea cultivars (BRS Novaera, BRS Tapaihum, BRS Pujante, and BRS Pajeú) were subjected to different treatments: control (W100: 100% replacement of crop evapotranspiration – ETc), W50 (50% of ETc), W50+SA2 (50% of ETc + 276 mg L-1 of SA), and W50+SA4 (50% of ETc + 552 mg L-1 of SA). The treatments were combined in a 4×4 factorial scheme with three replications, arranged in a randomized block design.ResultsWater restriction had a negative impact on the water status, growth, gas exchange, and production of the cultivars while also leading to changes in the antioxidant metabolism and osmolyte concentration. The application of SA enhanced antioxidant activity and the synthesis of osmotic adjusters under stress conditions. The most effective concentration was 276 mg L-1 in stage R2 and 552 mg L-1 in stage V7, respectively. The BRS Pujante cultivar showed increased productivity under water restriction with SA application, while the BRS Tapaihum was the most tolerant among the cultivars studied.DiscussionIn summary, our findings underscore the importance of using SA to mitigate the effects of water restriction on cowpea cultivation. These discoveries are crucial for the sustainability of cowpea production in regions susceptible to drought, which can contribute to food security. We further add that the adoption of new agricultural practices can enhance the resilience and productivity of cowpea as an essential and sustainable food source for vulnerable populations in various parts of the world.

Karl R VanDerMeid, Mirzi Grace Byrnes, Kimberly Millard, Catherine A Scheuer, Nitasha R Phatak, William Reindel Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USACorrespondence: Nitasha R Phatak, Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA, Tel +1 585-413-6397, Email nitasha.phatak@bausch.comPurpose: Contact lens (CL) wear challenges the balance of the ocular surface environment by increasing water evaporation and tear osmolarity. Maintaining ocular surface homeostasis during CL wear remains a goal of lens manufacturers and an important consideration for eye care professionals. The purpose of this study was to measure the metabolic activity and inflammatory responses of a transformed human corneal epithelial cell (THCEpiC) line under hyperosmotic conditions in the presence of CL packaging solutions.Methods: CL packaging solutions sampled from seven daily disposable silicone hydrogel CL blister packages were prepared at 25% and made hyperosmolar (400 mOsm/kg) with NaCl. THCEpiCs were incubated with each solution for 24 hr, after which cell culture supernatants were collected. THCEpiC metabolic activity was determined by an alamarBlue assay. Concentrations in cell culture supernatants of inflammatory cytokine (interleukin [IL]-6) and chemokine (IL-8), as well as monocyte chemoattractant protein-1 (MCP-1), were quantitated by specific enzyme-linked immunosorbent assays.Results: THCEpiC metabolic activity under hyperosmolar conditions decreased in the presence of somofilcon A and senofilcon A solutions (p=0.04 and 0.004, respectively), but no other solution (all p≥ 0.09). Concentrations of IL-6 increased in the presence of delefilcon A, somofilcon A, narafilcon A, and senofilcon A solutions (all p≤ 0.001), but no other solution (all p≥ 0.08), while those of IL-8 increased in the presence of all solutions (all p≤ 0.03) but kalifilcon A (p> 0.99), and those of MCP-1 increased in the presence of delefilcon A, verofilcon A, somofilcon A, and stenfilcon A solutions (all p< 0.0001), but no other solution (all p> 0.99).Conclusion: CL packaging solutions differ in their capacity to inhibit epithelial inflammation. THCEpiC inflammatory response was less in the presence of a CL packaging solution containing osmoprotectants than in solutions lacking osmoprotectants under moderately hyperosmolar conditions in vitro. Clinical studies are warranted to further substantiate the benefit of osmoprotectants.Keywords: contact lens, cornea, TFOS, hyperosmolarity, osmoprotection, homeostasis

To assess the potential of exogenously-applied vitamin E commonly known as alpha-tocopherol (α-TOC) in drought stress tolerance, an experiment was performed on cauliflower (Brassica oleracea L. var. botrytis) plants. Two cultivars (TCF-605 and White Figer) of cauliflower were subjected to control and drought stress conditions. After thirty days of drought stress treatment, cauliflower plants were treated with α-TOC (150 and 300 mg/L) as a foliage spray. Drought stress markedly inhibited the plant biomass, leaf characteristics such as relative water contents (RWC), chlorophyll pigments (a and b), proline, ascorbic acid (AsA), GB, however it elevated RMP, total phenolics, activities of antioxidant enzymes e.g., CAT, SOD and POD. Drought stress also adversely affected curd characteristics including its fresh weight, GB, proline, total phenolics and enzymes activities (SOD and CAT). Exogenously applied α-TOC considerably suppressed RMP, while it improved plant growth, yield, RWC, total phenolics, ascorbic acid and POD, SOD, and CAT enzyme activities in the leaves of the cauliflower. Exogenous application of α-TOC also raised curd total phenolics, AsA and the activities of all observed enzymes under water deficiency. The cv. TCF-605 was better in shoot weight, shoot length, RWC, proline as well as GB contents, while cv. White Figer was higher in leaf RMP, proline and AsA levels under drought stress conditions. Overall, the results exhibited that cauliflower cv. TCF-605 was relatively tolerant to water stress in relation to growth and yield outcomes, which was interlinked with α-TOC-induced improved leaf and curd osmoprotection and antioxidative defense system. So, exogenous application of α-TOC can be suggested for improving growth and yield potential of crops subjected to drought stress.

Purpose: The purpose of this study was to study the osmoprotective and bioprotective effect of trehalose 3% + carboxymethylcellulose (CMC) 0.5% during desiccation conditions. Materials and Methods: Normal human conjunctival epithelial cells (IOBA) were exposed to (1) culture media (control); (2) CMC 0.5% + glycerin 0. 9% + polyethylene glycol 400 0.25% (vehicle); and (3) vehicle + trehalose 3% (trehalose). Cells were treated for 1 h and then exposed to desiccating conditions. Metabolic activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell viability by trypan blue. Trehalose water retention capability was assessed by a gravimetric analysis. Results: Metabolic activity was maintained during the first 30 min under desiccating conditions with no differences found between groups. After 45 min, metabolic activity decreased both in the control group and the vehicle group, while the trehalose group maintained activity values. Cell viability of the trehalose group was maintained throughout time and was statistically superior to those of the control and the vehicle groups at all evaluated times (P < 0.01). The retention time 20-RT20 - (20% of water retention) was reached at 8 min in the control group, 10 min in the vehicle group, and 15 min in the trehalose group. Conclusions: The addition of 3% trehalose prolonged cell viability and extended water retention time in high-dryness environmental conditions. [ABSTRACT FROM AUTHOR]

High salt levels in soil can severely limit plant development and diminish the positive effect of plant-growth-promoting rhizobacteria (PGPR). However, extracts of organisms adapted to high salinity, such as Opuntia ficus-indica (OFI) and Enteromorpha intestinalis (EI), can restore the growth of PGPR. Therefore, we used OFI or EI extracts and their combination with the PGPR Achromobacter xylosoxidans BOA4 to evaluate salt stress relief in tomato (Solanum lycopersicum). The experimental setup consisted of a plant pot trial under greenhouse conditions with 12 treatments: control, irrigation with OFI extract; EI extract; BOA4-inoculated plus OFI extract and BOA4-inoculated plus EI extract under no salinity or salinity conditions (150 mM NaCl). The percentage of germination, and plant's fresh and dry weight were registered 30 and 46 days after sowing. At 46 days, the ratio between proline and glutamic acid concentration (PR/GA) was determined, expecting high PR/GA ratios in plants more responsive to salt stress since proline is an osmolyte mainly synthesized from glutamate. The results showed that 52% of the control seeds under salt stress germinated, a figure that was increased to 92% in OFI-treated seeds. Tomato plants were shown to be very sensitive to salt stress since the dry weight was ca. one fourth that of the plants grown without salinity. However, EI or BOA4 plus EI stimulated plant biomass by ca. 3 times compared to the control with salt, restoring plant biomass to values comparable to those of control plants grown without salinity. The joint treatments with BOA4 and EI or OFI caused distinct PR/GA levels in plant tissues. An inverse relationship between the sum of relative shoot proline and glutamic acid contents and shoot biomass accumulation was observed, namely in treatments accumulating more biomass under no salinity and salinity conditions. This indicates that the proline/glutamate pathway represents a carbon sink that is needed to fight stress and is competing with the carbon flow used for growth. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is a crucial industrial crop, particularly grown for fiber; however, its growth, development, and yield are substantially restricted by high salt stress. Salicylic acid (SA) is a crucial phytohormone, exhibiting a multifarious array of roles in the enhancement of plant growth, progression, and resilience to stress. In the current investigation, we provided persuasive evidence on the potential roles of exogenous SA in promoting salinity tolerance in cotton plants by investigating various morphological, biochemical, and physiological features. Our results showed that pre-application of SA to the root zones of cotton plants led to a substantial enhancement of plant biomass, individual leaf area, net photosynthetic rate, stomatal conductance, transpiration rate, water-use-efficiency, and chlorophyll, carotenoid and relative water contents in leaves, resulting in better growth performance of cotton under salt stress. SA pretreatment further diminished the salinity-induced accumulation of hydrogen peroxide, and the elevated levels of electrolyte leakage and malondialdehyde in the leaves of cotton plants. The SA-pretreated cotton plants experienced reduced oxidative burden because of improved antioxidant defense systems, as manifested by the enhanced activities of catalase, ascorbate peroxidase, peroxidase, and the levels of total flavonoids. Furthermore, the pretreatment with SA resulted in a remarkable elevation in the levels of total free amino acids and total soluble sugars in salt-stressed plants, indicating that SA utilized these compounds for optimal osmotic regulation in the plant tissues amidst adverse saline conditions. Importantly, the pretreatment with SA resulted in a substantial inhibition of Na+ uptake and a remarkable increase in the uptake of K+, Mg2+, and Ca2+ in both roots and leaves of cotton plants. Together, our findings suggest that SA pretreatment could be an effective strategy to increase the resiliency of cotton plants toward salinity, thereby enabling better performance of cotton plants in saline prone areas. [ABSTRACT FROM AUTHOR]

Prolonged drought presents a serious challenge to the agricultural sector. The main concern of this work was to assess the phenotypical, physiological, and molecular responses of five teosinte (Zea mexicana Schrad L.) genotypes (Ba, Gm1, Gm2, Gm3 and Gm4). In a two-season (2020 and 2021) field experiment, fifteen-day-old teosinte plants were subjected to well-watered (15-day watering frequency) as a control, moderate drought (25-day watering frequency), and extreme drought (35-day watering frequency) treatments. Drought negatively affected growth, yield, chlorophyll, and POD activity of all genotypes, but promoted soluble sugars and proteins, osmoregulatory molecules (glycinebetaine, amino acids, and proline), non-enzymatic antioxidants (phenols, flavonoids, and alkaloids), and SOD activity. Furthermore, long-term water stress upregulated MOCOS, Rad17, NCED1, CAT1, and P5CS genes expression, with Gm3 and Gm4 being the most drought-tolerant genotypes. These findings could be employed in breeding programs to develop tolerant genotypes to address the challenges posed by climate changes like drought.

Dry eye disease (DED) is a worldwide, multifactorial disease mainly caused by a deficit in tear production or increased tear evaporation with an increase in tear osmolarity and inflammation. This causes discomfort and there is a therapeutic need to restore the homeostasis of the ocular surface. The aim of the present work was to develop a biodegradable and biocompatible liposomal formulation from the synthetic phospholipids 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) that is able to reduce the effects of hypertonic stress by helping to restore the lipid layer of the tear film. Liposomes were made using the lipid film hydration method with synthetic phospholipids (10 mg/mL) with and without 0.2% HPMC. They were characterised in terms of size, osmolarity, pH, surface tension, and viscosity. Additionally, the in vitro toxicity of the formulation at 1 and 4 h in human corneal epithelial cells (hTERT-HCECs) and human conjunctival cells (IM-HConEpiC) was determined. Furthermore, osmoprotective activity was tested in a corneal model of hyperosmolar stress. In vivo acute tolerance testing was also carried out in albino New Zealand rabbits by topical application of the ophthalmic formulations every 30 min for 6 h. All the assayed formulations showed suitable physicochemical characteristics for ocular surface administration. The liposomal formulations were well-tolerated in cell cultures and showed osmoprotective activity in a hyperosmolar model. No alterations or discomfort were reported when they were topically administered in rabbits. According to the results, the osmoprotective liposomal formulations developed in this work are promising candidates for the treatment of DED. [ABSTRACT FROM AUTHOR]

High salt levels in soil can severely limit plant development and diminish the positive effect of plant-growth-promoting rhizobacteria (PGPR). However, extracts of organisms adapted to high salinity, such as Opuntia ficus-indica (OFI) and Enteromorpha intestinalis (EI), can restore the growth of PGPR. Therefore, we used OFI or EI extracts and their combination with the PGPR Achromobacter xylosoxidans BOA4 to evaluate salt stress relief in tomato (Solanum lycopersicum). The experimental setup consisted of a plant pot trial under greenhouse conditions with 12 treatments: control, irrigation with OFI extract; EI extract; BOA4-inoculated plus OFI extract and BOA4-inoculated plus EI extract under no salinity or salinity conditions (150 mM NaCl). The percentage of germination, and plant’s fresh and dry weight were registered 30 and 46 days after sowing. At 46 days, the ratio between proline and glutamic acid concentration (PR/GA) was determined, expecting high PR/GA ratios in plants more responsive to salt stress since proline is an osmolyte mainly synthesized from glutamate. The results showed that 52% of the control seeds under salt stress germinated, a figure that was increased to 92% in OFI-treated seeds. Tomato plants were shown to be very sensitive to salt stress since the dry weight was ca. one fourth that of the plants grown without salinity. However, EI or BOA4 plus EI stimulated plant biomass by ca. 3 times compared to the control with salt, restoring plant biomass to values comparable to those of control plants grown without salinity. The joint treatments with BOA4 and EI or OFI caused distinct PR/GA levels in plant tissues. An inverse relationship between the sum of relative shoot proline and glutamic acid contents and shoot biomass accumulation was observed, namely in treatments accumulating more biomass under no salinity and salinity conditions. This indicates that the proline/glutamate pathway represents a carbon sink that is needed to fight stress and is competing with the carbon flow used for growth.

Biofuels and other biologically manufactured sustainable goods are growing in popularity and demand. Carbohydrate feedstocks required for industrial fermentation processes have traditionally been supplied by plant biomass, but the large quantities required to produce replacement commodity products may prevent the long-term feasibility of this approach without alternative strategies to produce sugar feedstocks. Cyanobacteria are under consideration as potential candidates for sustainable production of carbohydrate feedstocks, with potentially lower land and water requirements relative to plants. Several cyanobacterial strains have been genetically engineered to export significant quantities of sugars, especially sucrose. Sucrose is not only naturally synthesized and accumulated by cyanobacteria as a compatible solute to tolerate high salt environments, but also an easily fermentable disaccharide used by many heterotrophic bacteria as a carbon source. In this review, we provide a comprehensive summary of the current knowledge of the endogenous cyanobacterial sucrose synthesis and degradation pathways. We also summarize genetic modifications that have been found to increase sucrose production and secretion. Finally, we consider the current state of synthetic microbial consortia that rely on sugar-secreting cyanobacterial strains, which are co-cultivated alongside heterotrophic microbes able to directly convert the sugars into higher-value compounds (e.g., polyhydroxybutyrates, 3-hydroxypropionic acid, or dyes) in a single-pot reaction. We summarize recent advances reported in such cyanobacteria/heterotroph co-cultivation strategies and provide a perspective on future developments that are likely required to realize their bioindustrial potential.

Prolonged drought presents a serious challenge to the agricultural sector. The main concern of this work was to assess the phenotypical, physiological, and molecular responses of five teosinte (Zea mexicana Schrad L.) genotypes (Ba, Gm1, Gm2, Gm3 and Gm4). In a two-season (2020 and 2021) field experiment, fifteen-day-old teosinte plants were subjected to well-watered (15-day watering frequency) as a control, moderate drought (25-day watering frequency), and extreme drought (35-day watering frequency) treatments. Drought negatively affected growth, yield, chlorophyll, and POD activity of all genotypes, but promoted soluble sugars and proteins, osmoregulatory molecules (glycinebetaine, amino acids, and proline), non-enzymatic antioxidants (phenols, flavonoids, and alkaloids), and SOD activity. Furthermore, long-term water stress upregulated MOCOS, Rad17, NCED1, CAT1, and P5CS genes expression, with Gm3 and Gm4 being the most drought-tolerant genotypes. These findings could be employed in breeding programs to develop tolerant genotypes to address the challenges posed by climate changes like drought. [ABSTRACT FROM AUTHOR]

Nonstructural carbohydrates (NSCs) mediate plant survival when the plant's carbon (C) balance is negative, suggesting that NSCs could predict plant survival under C stress. To examine this possibility, we exposed saplings of six temperate tree species to diverse levels of C stress created by the combination of two light conditions (full light availability and deep shade) and two defoliation levels (severe defoliation and nondefoliation). We then measured survival, biomass and total NSCs and soluble sugars (SSs) concentrations in different organs of both dead and live saplings.We estimated mean NSCs and SSs contents and concentrations per sapling and fitted logistic generalized mixed‐effects models to determine if NSCs and SSs predict survival. Using inverse prediction modelling, we also determined whether there is a common NSCs and SSs threshold across species at the time of sapling's death.Defoliation and shade reduced the mean sapling's NSCs and SSs contents, indicating C stress. Mean sapling NSCs and SSs contents and concentrations predicted survival and the robustness of the models improved with the inclusion of species. At death, saplings of the exotic deciduous tree species Acer pseudoplatanus exhibited significantly lower mean NSCs and SSs contents than saplings of the evergreen conifer species Podocarpus nubigenus and lower stem NSCs and SSs concentrations than the broadleaf evergreen species Drimys winteri.The energetic role that NSCs and SSs play in plants under C stress was evidenced by the capacity of these compounds to predict sapling survival under C stress. No common threshold of NSCs and SSs contents or concentrations for sapling survival amongst species was found, indicating that the level of these compounds may not be good proxies for interspecific comparisons of tolerance to C stress. Presumably, there are species‐specific limits for the mobilization and use of NSCs and SSs in metabolism.Our results anticipate that the inclusion of NSCs and SSs in modelling will improve predictions regarding tree responses to ongoing climate change. Nonetheless, a better understanding of the many roles that carbohydrates play in plant survival under C stress is required to scale predictions up to the community level. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Salt stress is one of the most serious abiotic stresses limiting plant growth and development. Calcium as an essential nutrient element and important signaling molecule plays an important role in ameliorating the adverse effect of salinity on plants. This study aimed to investigate the impact of exogenous calcium on improving salt tolerance in Tartary buckwheat cultivars, cv. Xinong9920 (salt-tolerant) and cv. Xinong9909 (salt-sensitive). Four-week-old Tartary buckwheat seedlings under 100 mM NaCl stress were treated with and without exogenous calcium chloride (CaCl2), Ca2+ chelator ethylene glycol tetraacetic acid (EGTA) and Ca2+-channel blocker lanthanum chloride (LaCl3) for 10 days. Then, some important physiological and biochemical indexes were determined. The results showed that salt stress significantly reduced seedling growth, decreased photosynthetic pigments, inhibited antioxidants and antioxidant enzyme activities. However, it increased the reactive oxygen species (ROS) levels in the two Tartary buckwheat cultivars. Exogenous 10 mM CaCl2 application on salt-stressed Tartary buckwheat seedlings obviously mitigated the negative effects of NaCl stress and partially restored seedlings growth. Ca2+-treated salt-stressed seedlings diplayed a suppressed accumulation of ROS, increased the contents of total chlorophyll, soluble protein, proline and antioxidants, and elevated the activities of antioxidant enzymes compared with salt stress alone. On the contrary, the addition of 0.5 mM LaCl3 and 5 mM EGTA on salt-stressed Tartary buckwheat seedlings exhibited the opposite effects to those with CaCl2 treatment. These results indicate that exogenous Ca2+ can enhance salt stress tolerance and Ca2+ supplementation may be an effective practice to cultivate Tartary buckwheat in saline soils. [ABSTRACT FROM AUTHOR]

Heat stress is one of the major abiotic factors that limit the growth, development, and productivity of plants. Both glycine betaine (GB) and β-aminobutyric acid (BABA) have received considerable attention due to their roles in stimulating tolerance to diverse abiotic stresses. In order to understand how GB and BABA biostimulants alleviate heat stress in a cool-weather Chinese cabbage (Brassica rapa L. ssp. pekinensis) plant, we investigated the GB- and BABA-primed heat-stressed plants in terms of their morpho-physiological and biochemical traits. Priming with GB (15 mM) and BABA (0.2 mM) was conducted at the third leaf stage by applying foliar sprays daily for 5 days before 5 days of heat stress (45 °C in 16 h light/35 °C in 8 h dark) on Chinese cabbage seedlings. The results indicate that GB and BABA significantly increased chlorophyll content, and the parameters of both gas exchange and chlorophyll fluorescence, of Chinese cabbage under heat stress. Compared with the unprimed heat-stressed control, the dry weights of GB- and BABA-primed plants were significantly increased by 36.36% and 45.45%, respectively. GB and BABA priming also greatly mitigated membrane damage, as indicated by the reduction in malondialdehyde (MDA) and electrolyte leakage through the elevation of proline content, and increased activity levels of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). Taken together, GB and BABA have great potential to enhance the thermotolerance of Chinese cabbage through higher photosynthesis performance, osmoprotection, and antioxidant enzyme activity. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to study the osmoprotective and bioprotective effect of trehalose 3% + carboxymethylcellulose (CMC) 0.5% during desiccation conditions. Materials and Methods: Normal human conjunctival epithelial cells (IOBA) were exposed to (1) culture media (control); (2) CMC 0.5% + glycerin 0. 9% + polyethylene glycol 400 0.25% (vehicle); and (3) vehicle + trehalose 3% (trehalose). Cells were treated for 1 h and then exposed to desiccating conditions. Metabolic activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell viability by trypan blue. Trehalose water retention capability was assessed by a gravimetric analysis. Results: Metabolic activity was maintained during the first 30 min under desiccating conditions with no differences found between groups. After 45 min, metabolic activity decreased both in the control group and the vehicle group, while the trehalose group maintained activity values. Cell viability of the trehalose group was maintained throughout time and was statistically superior to those of the control and the vehicle groups at all evaluated times (P < 0.01). The retention time 20-RT20 - (20% of water retention) was reached at 8 min in the control group, 10 min in the vehicle group, and 15 min in the trehalose group. Conclusions: The addition of 3% trehalose prolonged cell viability and extended water retention time in high-dryness environmental conditions.

Introduction: Salicylic acid has shown promise in alleviating water stress in cultivated plants. However, there is a lack of studies confirming its effectiveness in cowpea plants grown in field conditions. Therefore, this research aimed to evaluate the use of salicylic acid as a water stress mitigator in cowpea cultivars under different irrigation depths in field conditions., Methods: Four cowpea cultivars (BRS Novaera, BRS Tapaihum, BRS Pujante, and BRS Pajeú) were subjected to different treatments: control (W100: 100% replacement of crop evapotranspiration - ETc), W50 (50% of ETc), W50+SA2 (50% of ETc + 276 mg L -1 of SA), and W50+SA4 (50% of ETc + 552 mg L -1 of SA). The treatments were combined in a 4×4 factorial scheme with three replications, arranged in a randomized block design., Results: Water restriction had a negative impact on the water status, growth, gas exchange, and production of the cultivars while also leading to changes in the antioxidant metabolism and osmolyte concentration. The application of SA enhanced antioxidant activity and the synthesis of osmotic adjusters under stress conditions. The most effective concentration was 276 mg L -1 in stage R2 and 552 mg L -1 in stage V7, respectively. The BRS Pujante cultivar showed increased productivity under water restriction with SA application, while the BRS Tapaihum was the most tolerant among the cultivars studied., Discussion: In summary, our findings underscore the importance of using SA to mitigate the effects of water restriction on cowpea cultivation. These discoveries are crucial for the sustainability of cowpea production in regions susceptible to drought, which can contribute to food security. We further add that the adoption of new agricultural practices can enhance the resilience and productivity of cowpea as an essential and sustainable food source for vulnerable populations in various parts of the world., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cavalcante, de Melo, Ferraz, de Alencar, Dias, Viana, Rocha, Ndhlala, Sá, de Lacerda and Viégas.)

Purpose: To evaluate the effect of topical cyclosporine 0.05% and osmoprotective lubricating eye drops on patients with dry eye disease (DED) with inflammation as measured by raised tear matrix metalloproteinases (MMP-9).Methods: This prospective study included 106 eyes of 53 patients diagnosed with DED based on any of the following DED criteria (Ocular Surface Disease Index [OSDI] score >12, tear film breakup time [TBUT] <10 s, Schirmer's I test result <10 mm/5 min, ocular surface staining). Ocular surface inflammation was assessed by assessing MMP-9 positivity from tears of the patients in the study (Inflammadry kit Quidel corporation). Patients were prescribed osmoprotective lubricating eye drops (Osmodrops, Cipla Ltd) four times a day and cyclosporine A 0.05% eye drops (Imudrops, Cipla Ltd) twice a day for 6 months. Efficacy of the formulations was evaluated by OSDI scores, Schirmer's test, TBUT change, reduction in ocular surface staining, and reduction in MMP-9 levels after 6 months of usage. Check P value and add from results.Results: After 6 months of topical therapy, improvement was observed in OSDI scores (mean pretreatment: 25.7 ± 12.8, and mean posttreatment: 15.2 ± 8.4), P < 0.001. There was also reduction number of patients who were MMP-9 positive. Out of 75 eyes that tested MMP-9 positive, 70.66% showed reduction in MMP-9 levels P < 0.0001). Ocular surface staining also improved.Conclusion: Topical osmoprotective lubricating eye drops and cyclosporine A 0.05% reduce inflammation in cases of DED, which correlates with improvement in OSDI scores, ocular surface staining, and reduction in inflammation as measured by levels of tear MMP-9. [ABSTRACT FROM AUTHOR]

To assess the potential of exogenously-applied vitamin E commonly known as alpha-tocopherol (α-TOC) in drought stress tolerance, an experiment was performed on cauliflower (Brassica oleracea L. var. botrytis) plants. Two cultivars (TCF-605 and White Figer) of cauliflower were subjected to control and drought stress conditions. After thirty days of drought stress treatment, cauliflower plants were treated with α-TOC (150 and 300 mg/L) as a foliage spray. Drought stress markedly inhibited the plant biomass, leaf characteristics such as relative water contents (RWC), chlorophyll pigments (a and b), proline, ascorbic acid (AsA), GB, however it elevated RMP, total phenolics, activities of antioxidant enzymes e.g., CAT, SOD and POD. Drought stress also adversely affected curd characteristics including its fresh weight, GB, proline, total phenolics and enzymes activities (SOD and CAT). Exogenously applied α-TOC considerably suppressed RMP, while it improved plant growth, yield, RWC, total phenolics, ascorbic acid and POD, SOD, and CAT enzyme activities in the leaves of the cauliflower. Exogenous application of α-TOC also raised curd total phenolics, AsA and the activities of all observed enzymes under water deficiency. The cv. TCF-605 was better in shoot weight, shoot length, RWC, proline as well as GB contents, while cv. White Figer was higher in leaf RMP, proline and AsA levels under drought stress conditions. Overall, the results exhibited that cauliflower cv. TCF-605 was relatively tolerant to water stress in relation to growth and yield outcomes, which was interlinked with α-TOC-induced improved leaf and curd osmoprotection and antioxidative defense system. So, exogenous application of α-TOC can be suggested for improving growth and yield potential of crops subjected to drought stress. [ABSTRACT FROM AUTHOR]

The chronic use of hypotensive agents eventually leads to ocular surface damage and poor patient compliance during glaucoma management. Thus, new sustained drug delivery systems are needed. This work aimed to develop osmoprotective latanoprost-loaded microemulsion formulations as new potential glaucoma treatments with ocular surface protective properties. The microemulsions were characterized and latanoprost encapsulation efficacy determined. In-vitro tolerance, osmoprotective efficacy, cell internalization as well as cell-microemulsion interactions and distribution were performed. In vivo hypotensive activity was conducted in rabbits to assess intraocular pressure reduction and relative ocular bioavailability. Physicochemical characterization showed nanodroplet sizes within 20-30 nm, being in vitro tolerance within 80 and 100% viability in corneal and conjunctival cells. Besides, microemulsions exhibited higher protection under hypertonic conditions than untreated cells. Cell fluorescence lasted for 11 days after short exposure to coumarin-loaded microemulsions (5 min) showing extensive internalization in different cell compartments by electronic microscopy. In vivo studies exhibited that a single instillation of latanoprost-loaded microemulsions reduced the intraocular pressure for several days (4-6 days without polymer and 9-13 days with polymers). Relative ocular bioavailability was 4.5 and 19 times higher than the marketed formulation. These findings suggest the use of these microemulsions as potential combined strategies for extended surface protection and glaucoma treatment., Competing Interests: Declaration of competing interest The authors declare no conflict of interest in any subjects treated in the present work., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) are major regulators of gene expression during plant development under normal and stress conditions. In this study, we analyzed the expression of 150 conserved miRNAs during drought stress applied to barley ready to flower. The dynamics of miRNAs expression was also observed after rewatering. Target messenger RNA (mRNAs) were experimentally identified for all but two analyzed miRNAs, and 41 of the targets were not reported before. Drought stress applied to barley induced accelerated flowering coordinated by a pair of two differently expressed miRNAs originating from a single precursor: hvu-miR172b-3p and hvu-miR172b-5p. Increased expression of miRNA172b-3p during drought leads to the downregulation of four APETALA2(AP2)-like genes by their mRNA cleavage. In parallel, the downregulation of the miRNA172b-5p level results in an increased level of a newly identified target, trehalose-6-phosphate synthase, a key enzyme in the trehalose biosynthesis pathway. Therefore, drought-treated plants have higher trehalose content, a known osmoprotectant, whose level is rapidly dropping after watering. In addition, trehalose-6-phosphate, an intermediate of the trehalose synthesis pathway, is known to induce flowering. The hvu-miRNA172b-5p/trehalose-6-phosphate synthase and hvu-miRNA172b-3p/AP2-like create a module leading to osmoprotection and accelerated flowering induction during drought., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Swida-Barteczka, Pacak, Kruszka, Nuc, Karlowski, Jarmolowski and Szweykowska-Kulinska.)

Biofuels and other biologically manufactured sustainable goods are growing in popularity and demand. Carbohydrate feedstocks required for industrial fermentation processes have traditionally been supplied by plant biomass, but the large quantities required to produce replacement commodity products may prevent the long-term feasibility of this approach without alternative strategies to produce sugar feedstocks. Cyanobacteria are under consideration as potential candidates for sustainable production of carbohydrate feedstocks, with potentially lower land and water requirements relative to plants. Several cyanobacterial strains have been genetically engineered to export significant quantities of sugars, especially sucrose. Sucrose is not only naturally synthesized and accumulated by cyanobacteria as a compatible solute to tolerate high salt environments, but also an easily fermentable disaccharide used by many heterotrophic bacteria as a carbon source. In this review, we provide a comprehensive summary of the current knowledge of the endogenous cyanobacterial sucrose synthesis and degradation pathways. We also summarize genetic modifications that have been found to increase sucrose production and secretion. Finally, we consider the current state of synthetic microbial consortia that rely on sugar-secreting cyanobacterial strains, which are co-cultivated alongside heterotrophic microbes able to directly convert the sugars into higher-value compounds (e.g., polyhydroxybutyrates, 3-hydroxypropionic acid, or dyes) in a single-pot reaction. We summarize recent advances reported in such cyanobacteria/heterotroph co-cultivation strategies and provide a perspective on future developments that are likely required to realize their bioindustrial potential., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Santos-Merino, Yun and Ducat.)

To examine the potential role of acetate in conferring cadmium (Cd) stress tolerance in lentil (Lens culinaris), several phenotypical and physio-biochemical properties have been examined in Cd-stressed lentil seedlings following acetate applications. Acetate treatment inhibited the translocation of Cd from roots to shoots, which resulted in a minimal reduction in photosynthetic pigment contents. Additionally, acetate-treated lentil showed higher shoot (1.1 and 11.72%) and root (4.98 and 30.64%) dry weights compared with acetate-non-treated plants under low-Cd and high-Cd concentrations, respectively. Concurrently, acetate treatments increase osmoprotection under low-Cd stress through proline accumulation (24.69%), as well as enhancement of antioxidant defense by increasing ascorbic acid content (239.13%) and catalase activity (148.51%) under high-Cd stress. Acetate-induced antioxidant defense resulted in a significant diminution in hydrogen peroxide, malondialdehyde and electrolyte leakage in Cd-stressed lentil seedlings. Our results indicated that acetate application mitigated oxidative stress-induced damage by modulating antioxidant defense and osmoprotection, and reducing root-to-shoot Cd transport. These findings indicate an important contribution of acetate in mitigating the Cd toxicity during growth and development of lentil seedlings, and suggest that the exogenous applications of acetate could be an economical and new avenue for controlling heavy metal-caused damage in lentil, and potentially in many other crops. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microemulsions are novel platforms for the treatment of dry eye disease. • Osmoprotective microemulsions avoid cell death induced by chronic hyperosmolarity. • Ophthalmic microemulsions presented higher stability at 8 °C than 25 °C within 9 months of storage presenting superior stability after hyaluronic acid or dextran addition. • The microemulsions developed exhibited suitable physicochemical properties for topical ophthalmic administration. • In vitro and In vivo experiments demonstrated the good tolerability of the osmoprotective microemulsions. Self-emulsified osmoprotective ophthalmic microemulsions (O/A) were prepared by combining betaine/leucine, clusterin/oleanolic acid, and hyaluronic acid or Dextran. The microemulsions contained an internal oily phase (1.2%), an external aqueous phase (96.3%), cosolvents (1%), and surfactants (1.5%). Physicochemical characterization and in vivo and in vitro tolerance were analyzed. The formulations' osmoprotective in vitro activity was assayed in a hyperosmolar model in human corneal cells. Average internal phase sizes were 16–26 nm for the microemulsions including Dextran. Addition of hyaluronic acid increased the size range (25–39 nm). Addition of osmoprotectants did not change nanodroplet size. The formulations were isotonic (280–290 mOsm/L) with neutral pH (≈7) and zeta potential (−10 to 0 mV), low surface tension (≈35–40 mN·m−1), and low viscosity (≈1 mPa·s), except for the microemulsions containing hyaluronic acid (≈4–5 mPa·s). SEM and cryo-TEM showed that all formulations exhibited sphere-shaped morphology with good cell tolerance (≈100%) and were stable at 8 °C for 9 months. Osmoprotective formulations were well tolerated in vitro and in vivo , protecting cells from hypertonic stress. We therefore developed stable microemulsions compatible with the ocular surface that could constitute a novel tool for treatment of ophthalmic diseases. [ABSTRACT FROM AUTHOR]