Plant endogenous mechanisms are not always sufficient enough to mitigate drought stress, therefore, the exogenous application of elicitors, such as salicylic acid, is necessary. In this study, we ...assessed the mitigating action of salicylic acid (SA) in cowpea genotypes under drought conditions. An experiment was conducted with two cowpea genotypes and six treatments of drought stress and salicylic acid (T1 = Control, T2 = drought stress (stress), T3 = stress + 0.1 mM of SA, T4 = stress + 0.5 mM of SA, T5 = stress + 1.0 mM of SA, and T6 = stress + 2.0 mM of SA). Plants were evaluated in areas of leaf area, stomatal conductance, photosynthesis, proline content, the activity of antioxidant enzymes, and dry grain production. Drought stress reduces the leaf area, stomatal conductance, photosynthesis, and, consequently, the production of both cowpea genotypes. The growth and production of the BRS Paraguaçu genotype outcompetes the Pingo de Ouro-1-2 genotype, regardless of the stress conditions. The exogenous application of 0.5 mM salicylic acid to cowpea leaves increases SOD activity, decreases CAT activity, and improves the production of both genotypes. The application of 0.5 mM of salicylic acid mitigates drought stress in the cowpea genotype, and the BRS Paraguaçu genotype is more tolerant to drought stress.
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.
The association between population increase and the exploitation of natural resources and climate change influences the demand for food, especially in semi-arid regions, highlighting the need for ...technologies that could provide cultivated species with better adaptation to agroecosystems. Additionally, developing cultivation technologies that employ waste materials is highly desirable for sustainable development. From this perspective, this study aimed to evaluate whether seed priming with glass waste microparticles used as a silicon source under red light irradiation mitigates the effects of thermal and water stress on seedlings of Moringa oleifera. The experimental design was set up in randomized blocks using a 2 × 2 × 2 factorial arrangement consisting of seed priming (NSP—no seed priming, and SPSi—seed priming with glass microparticles under red light irradiation), soil water replenishment (W50—50%, and W100—100% of crop evapotranspiration—ETc), and temperature change (TC30°—30 °C day/25 °C night and TC40°—40 °C day/35 °C night). Seed priming with glass microparticles under red light irradiation mitigated the effects of thermal and water stress on seedlings of Moringa oleifera seedlings through the homeostasis of gas exchange, leaf water status, osmotic adjustment, and the antioxidant mechanism.
Global climate changes have intensified water stress in arid and semi-arid regions, reducing plant growth and yield. In this scenario, the present study aimed to evaluate the mitigating action of ...salicylic acid and methionine in cowpea cultivars under water restriction conditions. An experiment was conducted in a completely randomized design with treatments set up in a 2 × 5 factorial arrangement corresponding to two cowpea cultivars (BRS Novaera and BRS Pajeú) and five treatments of water replenishment, salicylic acid, and methionine. After eight days, water stress decreased the Ψw, leaf area, and fresh mass and increased the total soluble sugars and catalase activity in the two cultivars. After sixteen days, water stress increased the activity of the superoxide dismutase and ascorbate peroxidase enzymes and decreased the total soluble sugars content and catalase activity of BRS Pajeú plants. This stress response was intensified in the BRS Pajeú plants sprayed with salicylic acid and the BRS Novaera plants with salicylic acid or methionine. BRS Pajeú is more tolerant to water stress than BRS Novaera; therefore, the regulations induced by the isolated application of salicylic acid and methionine were more intense in BRS Novaera, stimulating the tolerance mechanism of this cultivar to water stress.
Cowpea is an important food crop in the Brazilian semiarid region due to its high nutritional value. In this region, water restriction is a factor that implies negative consequences for plant growth ...and grain yield. Thus, the use of new techniques to increase the tolerance of plants is required. Therefore, this study aimed to evaluate the effects of silicon foliar spray on the induction of tolerance to water stress in cowpea genotypes. The assay was conducted in a randomized block design, in a factorial scheme (2 × 2 × 3), with five replications. The treatments tested were two cowpea genotypes (“BRS Rouxinol” and “Costela de Vaca”) under two water conditions: control (without water deficit) and water stress (with water deficit) and three doses of silicon (0, 49, and 70 mg L
−1
of Si), resulting in 12 treatments. The water stress significantly reduced all variables of crop production in both genotypes. However, in the plants of Costela de Vaca genotype, the leaf spraying with 49 and 70 mg L
−1
Si increased the dry mass of pods + grains by 131 and 38%, respectively, when compared to dose 0 mg L
−1
. Si attenuates the negative effects of water stress in cowpea plants, but their physiological and biochemical responses, and consequently, their agronomic performance, are related to the sensitivity of genotype and their phenological stages. The Costela de Vaca genotype was the better between the genotypes tested.
•Silicon glass microparticles (SiMPs) induce tolerance to abiotic stresses.•Seed priming mitigated the effects of water restriction in cowpea plants.•Therefore, plants from seeds subjected to SP ...improve tolerance to water stress.
The northeast region of Brazil presents high variations in solar radiation levels and high air temperatures, impairing the growth and production of cowpea, consequently raising the need for technologies to improve the adaptation of cultivated plants. Therefore, this work aimed to promote the tolerance of cowpea (cultivar BRS Itaim) to water deficit induced by polyethylene glycol 6000 through seed conditioning with silicon glass microparticles. The experiment was performed in the field using a completely randomized 6 × 2 factorial scheme design with four replications. Seed priming (SP) consisted of six combinations of water potential (Ψw) and silicon glass microparticles (SiMPs) (T1: Ψw 0 + 0 SiMPs, T2: Ψw 0 + 200 SiMPs, T3: Ψw -0.4 + 0 SiMPs, T4: Ψw -0.4 + 200 SiMPs, T5: Ψw -0.8 + 0 SiMPs, and T6: Ψw -0.8 + 200 SiMPs) and two water replacement levels: plants with water restriction (50 % of water consumption) and without it (100 % of water consumption). Seed priming with silicon glass microparticles and polyethylene glycol 6000 attenuated the deleterious effects of water restriction in cowpea plants through water status homeostasis, osmotic adjustment, and antioxidant mechanism.
Candida species are normally commensal yeasts residing in the human body, under certain circumstances, can trigger pathological conditions such as candidiasis, not to mention antifungal resistance. ...Lippia sidoides Cham., or pepper-rosmarinus, is a native plant found in the Northeastern semi-arid region of Brazil, cited in ethnobotanical studies for its bioactive potential. This approach aims not only to expand the understanding of the antifungal efficacy of the ethanol extract of L. sidoides (EELs) but also to evaluate synergies that may enhance the available therapeutic arsenal, using the checkerboard method, and to assess potential toxic effects of this extract using model organisms, Artemia salina and Drosophila melanogaster, to evaluate mortality rates. Antifungal activity was observed at high concentrations (>1024 μg/mL) for both strains of Candida albicans and Candida krusei tested, with the most significant inhibition of fungal growth when the compound was used in synergy with fluconazole at 8.0 and 128 μg/mL, respectively. This activity likely occurred due to the interaction between the chemical composition of the ethanol extract rich in flavonoids and tannins with the reference drug. Regarding toxicity, both in relation to D. melanogaster and A. salina, no toxic results were observed at low concentrations. These results suggest that the ethanol extract of EELs may be a potential alternative as an adjuvant to fluconazole in the treatment of fungal infections caused by Candida spp. The observed synergy suggests that this combination may help overcome resistance to conventional antifungals and improve treatment efficacy.
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•The ethanolic extract of L. sidoides is rich in flababenic tannins, flavonoids and flavones.•The extract has a remarkable-potentiating effect on the fluconazole, mainly for C. albicans.•The extract did not present significant toxicity to model organisms at low concentrations.
Pharmacological studies show spasmolytic activity for various species of
. Thus, based on the taxonomy criteria, the aim of this study was to contribute to chemical and biological knowledge, ...especially regarding the evaluation of spasmolytic activity of the ethanolic extract from
leaves (VD-EtOH
) on rat aorta and trachea, guinea-pig ileum and rat uterus. Were used High and Medium Performance Liquid Chromatography. Wistar rats and guinea-pigs were used for pharmacological assays. All experimental protocols were approved by Animal Ethics Committee of UFPB (126/2017). Two chalcones (pinostrobin chalcone and gymnogrammene), five flavanones (pinocembrin, isosakuranetin, pinostrobin, sakuranetin 4'-methyl ether, naringenin) and a flavonoid glycosilated (astragalin) were identified based on data of
H and
C Nuclear Magnetic Resonance. This study also showed that VD-EtOH
has a non-selective spasmolytic activity, presenting greater relaxing potency in rat uterus, suggesting that flavonoids isolated from VD-EtOH
may be responsible for spasmolytic activity of this extract.
Pharmacological studies show spasmolytic activity for various species of Varronia. Thus, based on the taxonomy criteria, the aim of this study was to contribute to chemical and biological knowledge, ...especially regarding the evaluation of spasmolytic activity of the ethanolic extract from Varronia dardani leaves (VD-EtOH
L
) on rat aorta and trachea, guinea-pig ileum and rat uterus. Were used High and Medium Performance Liquid Chromatography. Wistar rats and guinea-pigs were used for pharmacological assays. All experimental protocols were approved by Animal Ethics Committee of UFPB (126/2017). Two chalcones (pinostrobin chalcone and gymnogrammene), five flavanones (pinocembrin, isosakuranetin, pinostrobin, sakuranetin 4'-methyl ether, naringenin) and a flavonoid glycosilated (astragalin) were identified based on data of
1
H and
13
C Nuclear Magnetic Resonance. This study also showed that VD-EtOH
L
has a non-selective spasmolytic activity, presenting greater relaxing potency in rat uterus, suggesting that flavonoids isolated from VD-EtOH
L
may be responsible for spasmolytic activity of this extract.
•There was an association between inadequacies in protein and energy supply with mortality.•Prone body positioning impacted the nutritional therapy.•Our results regarding enteral nutritional support ...showed that most individuals studied received inadequate caloric input.
Nutrition has become an important component in treating individuals during the coronavirus disease of 2019 (COVID-19) pandemic, which is increasingly affecting the world population and causing a collapse in health services. Prolonged hospitalization, including immobilization and catabolism, induces a decrease in body weight and muscle mass that may result in sarcopenia, a condition that impairs respiratory and cardiac function and worsens the prognosis. The present study aimed to analyze enteral nutritional support and the clinical evolution of patients admitted with COVID-19 in Brazil.
This was a retrospective study, conducted from March to May 2020, of patients admitted to a referral hospital in cardiology and pulmonology in Fortaleza-Ce/Brazil. Two hundred patients infected with COVID-19 were selected for the study. Sociodemographic, clinical, and nutritional data were collected from electronic medical records, and associations between outcomes and the use of the prone body position with nutritional variables were analyzed by linear regression. Odds ratio and 95% confidence interval estimates for the death outcome were analyzed by logistic regression.
Of the 112 patients who were fed by enterally, the majority were male (n = 61; 54.5%), elderly (n = 88; 78.6%), and with no current smoking habit (n = 81; 72.3%). The median hospital stay was 14 d, mostly in intensive care units (median: 9 d). Prone body positioning impacted the nutritional therapy. In general, patients who maintained a prone body position tested lower for kcal/kg of body weight, protein/kg of body weight, percentage of diet adequacy, and total caloric value. In addition, patients who died had a lower mean maximum kcal/kg body weight, protein/kg body weight, percentage of diet adequacy, and total caloric value compared with surviving patients.
An association between inadequacies in protein and energy supply with mortality was confirmed, suggesting that nutritional support optimization should be prescribed in such situations.
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