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1.
Ecotoxicol Environ Saf ; 202: 110851, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32673966

RESUMO

Arsenic is a harmful and toxic substance to the growth and development of plants. Salicylic acid (SA) acts as a signaling molecule, plays pivotal roles in the overall growth and development of plants under various environmental stresses. Artemisinin extracted from the leaves of A. annua helps in malarial treatment. The present investigation is aimed to find out the possible ameliorative role of exogenously-applied salicylic acid (SA) on two varieties of Artemisia annua L., namely 'CIM-Arogya' and 'Jeevan Raksha' under arsenic (As) stress conditions. For this, growth, physiological and biochemical characterization, and artemisinin production was assessed. The various treatments applied on the plants were Control, 10-6 M SA, 10-5 M SA, 45 mg kg-1As, 45 mg kg-1 As + 10-6 M SA, and 45 mg kg-1 As + 10-5 M SA. Arsenic at 45 mg kg-1 of soil, reducing the overall performance of both varieties at 90 and 120 DAP. However, the levels of antioxidants were enhanced in As-stressed plants, and the supplementation of SA further increased these antioxidants in SA-treated plants. It has been observed that minimum reduction in growth and yield occurs with enhanced production of artemisinin in the case of 'CIM-Arogya' compared to 'Jeevan Raksha' under As stress (45 mg kg-1 of soil). Leaf-applied SA significantly increased the content (49.0% & 43.4%) and yield (53.3% & 46.3%) of artemisinin in both tolerant and sensitive varieties as compared to their respective controls. Thus, the variety 'CIM-Arogya' showed tolerant behavior over 'Jeevan Raksha' and is much adapted to higher As stress.


Assuntos
Arsênico/toxicidade , Artemisia annua/fisiologia , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Artemisia annua/crescimento & desenvolvimento , Artemisia annua/metabolismo , Artemisininas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Oxidativo , Folhas de Planta/metabolismo , Ácido Salicílico/farmacologia , Solo , Estresse Fisiológico/efeitos dos fármacos
2.
PLoS One ; 15(5): e0232756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407323

RESUMO

Mitogen-activated protein kinase (MAPK) is a form of serine/threonine protein kinase that activated by extracellular stimulation acting through the MAPK cascade (MAPKKK-MAPKK-MAPK). The MAPK cascade gene family, an important family of protein kinases, plays a vital role in responding to various stresses and hormone signal transduction processes in plants. In this study, we identified 14 CmMAPKs, 6 CmMAPKKs and 64 CmMAPKKKs in melon genome. Based on structural characteristics and a comparison of phylogenetic relationships of MAPK gene families from Arabidopsis, cucumber and watermelon, CmMAPKs and CmMAPKKs were categorized into 4 groups, and CmMAPKKKs were categorized into 3 groups. Furthermore, chromosome location revealed an unevenly distribution on chromosomes of MAPK cascade genes in melon, respectively. Eventually, qRT-PCR analysis showed that all 14 CmMAPKs had different expression patterns under drought, salt, salicylic acid (SA), methyl jasmonate (MeJA), red light (RL), and Podosphaera xanthii (P. xanthii) treatments. Overall, the expression levels of CmMAPK3 and CmMAPK7 under different treatments were higher than those in control. Our study provides an important basis for future functional verification of MAPK genes in regulating responses to stress and signal substance in melon.


Assuntos
Cucumis melo/enzimologia , Cucumis melo/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Sistema de Sinalização das MAP Quinases/genética , Acetatos/farmacologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Cromossomos de Plantas/genética , Cucumis melo/efeitos dos fármacos , Ciclopentanos/farmacologia , Secas , Éxons/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Íntrons/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/química , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxilipinas/farmacologia , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Domínios Proteicos , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/genética , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
3.
Food Chem ; 327: 127057, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464461

RESUMO

Chilling injury (CI) restricts the quality and shelf life of bell pepper fruits; reducing these CI-induced detrimental effects is therefore of high economic and agricultural relevance. Here, we investigated the effects of trisodium phosphate (TSP), salicylic acid (SA), and TSP + SA treatments on pepper fruits under cold stress at 4 °C for 25 d. Combined TSP + SA treatment performed an optimal effect. Specifically, TSP + SA treatment enhanced fatty-acid desaturation efficiency, as indicated by the increased expression of key fatty acid desaturase genes, and higher content of unsaturated fatty acids. Meanwhile, TSP + SA treatment inhibited the CI-induced membrane damage, manifested as lower electrolyte leakage and malondialdehyde content. Furthermore, low field-nuclear magnetic resonance and proline content also revealed that TSP + SA treatment mitigated CI through enhancing water retention in pepper fruits. Collectively, our results may shed new light on optimizing the low-temperature storage conditions of post-harvest peppers.


Assuntos
Capsicum/química , Ácidos Graxos/química , Fosfatos/química , Ácido Salicílico/química , Água/química , Capsicum/efeitos dos fármacos , Capsicum/metabolismo , Parede Celular/efeitos dos fármacos , Temperatura Baixa , Ácidos Graxos/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malondialdeído/química , Malondialdeído/metabolismo , Permeabilidade/efeitos dos fármacos , Fosfatos/farmacologia , Prolina/química , Ácido Salicílico/farmacologia
4.
J Plant Physiol ; 250: 153184, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32464590

RESUMO

Although it is well known that parasitic weeds such as Orobanche (broomrape) significantly reduce the yield of economically important crops, their infection-induced oxidative changes need more exploration in their host plants. Moreover, applying an eco-friendly approach to minimize the infection is not yet available. This study was conducted to understand the effect of Orobanche ramosa infection on oxidative and redox status of tomato plants and the impact of hormonal (indole acetic acid (IAA); 0.09 mM and salicylic acid (SA); 1.0 mM) seed-priming upon mitigating the infection threats. Although Orobanche invades tomato roots, its inhibitory effects on shoot biomass were also indicted. Orobanche infection usually induces oxidative damage i.e., high lipid peroxidation, lipoxygenase activity and H2O2 levels, particularly for roots. Interestingly, hormonal seed-priming significantly enhanced tomato shoots and roots growth under both healthy and infected conditions. Also, IAA and SA treatment significantly reduced Orobanche infection-induced oxidative damage. The protective effect of seed-priming was explained by increasing the antioxidant defense markers including the antioxidant metabolites (i.e., total antioxidant capacity, carotenoids, phenolics, flavonoids, ASC, GSH, tocopherols) and enzymes (CAT, POX, GPX, SOD, GR, APX, MDHAR, DHAR), particularly in infected tomato seedlings. Additionally, cluster analysis indicated the differential impact of IAA- and SA-seed-priming, whereas lower oxidative damage and higher antioxidant enzymes' activities in tomato root were particularly reported for IAA treatment. The principal component analysis (PCA) also proclaimed an organ specificity depending on their response to Orobanche infection. Collectively, here and for the first time, we shed the light on the potential of seed-priming with either IAA or SA to mitigate the adverse effect of O. ramosa stress in tomato plants, especially at oxidative stress levels.


Assuntos
Ácidos Indolacéticos/farmacologia , Lycopersicon esculentum/fisiologia , Orobanche/fisiologia , Estresse Oxidativo/fisiologia , Reguladores de Crescimento de Planta/farmacologia , Plantas Daninhas/fisiologia , Ácido Salicílico/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/parasitologia , Estresse Oxidativo/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/parasitologia , Sementes/fisiologia
5.
PLoS One ; 15(5): e0232269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32357181

RESUMO

Susceptibility of plants to abiotic stresses, including extreme temperatures, salinity and drought, poses an increasing threat to crop productivity worldwide. Here the drought-induced response of maize was modulated by applications of methyl jasmonate (MeJA) and salicylic acid (SA) to seeds prior to sowing and to leaves prior to stress treatment. Pot experiments were conducted to ascertain the effects of exogenous applications of these hormones on maize growth, physiology and biochemistry under drought stress and well-watered (control) conditions. Maize plants were subjected to single as well as combined pre-treatments of MeJA and SA. Drought stress severely affected maize morphology and reduced relative water content, above and below-ground biomass, rates of photosynthesis, and protein content. The prolonged water deficit also led to increased relative membrane permeability and oxidative stress induced by the production of malondialdehyde (from lipid peroxidation), lipoxygenase activity (LOX) and the production of H2O2. The single applications of MeJA and SA were not found to be effective in maize for drought tolerance while the combined pre-treatments with exogenous MeJA+SA mitigated the adverse effects of drought-induced oxidative stress, as reflected in lower levels of lipid peroxidation, LOX activity and H2O2. The same pre-treatment also maintained adequate water status of the plants under drought stress by increasing osmolytes including proline, total carbohydrate content and total soluble sugars. Furthermore, exogenous applications of MeJA+SA approximately doubled the activities of the antioxidant enzymes catalase, peroxidase and superoxide dismutase. Pre-treatment with MeJA alone gave the highest increase in drought-induced production of endogenous abscisic acid (ABA). Pre-treatment with MeJA+SA partially prevented drought-induced oxidative stress by modulating levels of osmolytes and endogenous ABA, as well as the activities of antioxidant enzymes. Taken together, the results show that seed and foliar pre-treatments with exogenous MeJA and/or SA can have positive effects on the responses of maize seedlings to drought.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Secas , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Ácido Salicílico/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Antioxidantes/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Concentração Osmolar , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Sementes/efeitos dos fármacos , Solo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
6.
PLoS One ; 15(4): e0231426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271848

RESUMO

Demand for agricultural crop continues to escalate in response to increasing population and damage of prime cropland for cultivation. Research interest is diverted to utilize soils with marginal plant production. Moisture stress has negative impact on crop growth and productivity. The plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGR) are vital for plant developmental process under moisture stress. The current study was carried out to investigate the effect of PGPR and PGRs (Salicylic acid and Putrescine) on the physiological activities of chickpea grown in sandy soil. The bacterial isolates were characterized based on biochemical characters including Gram-staining, P-solubilisation, antibacterial and antifungal activities and catalases and oxidases activities and were also screened for the production of indole-3-acetic acid (IAA), hydrogen cyanide (HCN) and ammonia (NH3). The bacterial strains were identified as Bacillus subtilis, Bacillus thuringiensis and Bacillus megaterium based on the results of 16S-rRNA gene sequencing. Chickpea seeds of two varieties (Punjab Noor-2009 and 93127) differing in sensitivity to drought were soaked for 3 h before sowing in fresh grown cultures of isolates. Both the PGRs were applied (150 mg/L), as foliar spray on 20 days old seedlings of chickpea. Moisture stress significantly reduced the physiological parameters but the inoculation of PGPR and PGR treatment effectively ameliorated the adverse effects of moisture stress. The result showed that chickpea plants treated with PGPR and PGR significantly enhanced the chlorophyll, protein and sugar contents. Shoot and root fresh (81%) and dry weights (77%) were also enhanced significantly in the treated plants. Leaf proline content, lipid peroxidation and antioxidant enzymes (CAT, APOX, POD and SOD) were increased in reaction to drought stress but decreased due to PGPR. The plant height (61%), grain weight (41%), number of nodules (78%) and pod (88%), plant yield (76%), pod weight (53%) and total biomass (54%) were higher in PGPR and PGR treated chickpea plants grown in sandy soil. It is concluded from the present study that the integrative use of PGPR and PGRs is a promising method and eco-friendly strategy for increasing drought tolerance in crop plants.


Assuntos
Agricultura , Bacillaceae/fisiologia , Cicer/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/farmacologia , Amônia/metabolismo , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Bacillus megaterium/genética , Bacillus megaterium/isolamento & purificação , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Bacillus subtilis/fisiologia , Biomassa , Clorofila/análise , Cicer/efeitos dos fármacos , Cicer/metabolismo , Ácidos Indolacéticos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Putrescina/metabolismo , Putrescina/farmacologia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Chuva , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Microbiologia do Solo
7.
Artigo em Inglês | MEDLINE | ID: mdl-32193034

RESUMO

Implications of the role of antioxidant buffering in reactive oxygen species (ROS)-antioxidant interactions and associated redox regulation during adventitious root formation (ARF) were assessed in redox-manipulated salicylic acid (SA)-treated hypocotyl explants of mung bean [Vigna radiata (L.) R. Wilczek]. Application of pro-oxidant H2O2 (500 µM) followed by SA (600 µM) was shown to stimulate ARF, whereas treatments combining 600 µM SA and 10 × 10-4 M DPI (diphenyleneiodonium, an inhibitor of NADPH-oxidase) and 600 µM and SA 10 × 10-4 M (dimethylthiourea, a free radical scavenger) were found to prevent ARF. The redox status of the experimental explants monitored under such treatment conditions (in terms of accumulation of pro-oxidants, in situ localization of O2- and H2O2, radical scavenging property and total thiol content) revealed significant changes in ROS-antioxidant interactions at the metabolic interface, causing alterations in the pattern of ARF. Further, the assessment of activities and transcript abundance of the enzymes of the H2O2 turnover pathway (mainly the ascorbate-glutathione system) supported the transcriptional regulation of genes such as vrrboh, vrAPX, vrGR, vrSOD, and vrCAT and the activities of the relevant enzymes necessary for the generation of endogenous redox cues during ARF. The present work provides an inventory in support of the importance of antioxidant buffering associated with redox regulation for the origin of the metabolic redox cue (redox signal) necessary for SA-induced ARF in mung bean.


Assuntos
Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Oxidantes/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Vigna/metabolismo , Oxirredução , Raízes de Plantas/efeitos dos fármacos
8.
Artigo em Inglês | MEDLINE | ID: mdl-32087537

RESUMO

Chemical stimulants, used to enhance biomass yield, are highly desirable for the commercialisation of algal products for a wide range of applications in the food, pharma and biofuels sectors. In the present study, phenolic compounds, varying in substituents and positional isomers on the arene ring have been evaluated to determine structure-activity relationship and growth. The phenols, catechol, 4-methylcatechol and 2, 4-dimethyl phenol were generally inhibitory to growth as were the compounds containing an aldehyde function. By contrast, the phenolic acids, salicylic acid, aspirin and 4-hydroxybenzoate markedly stimulated cell proliferation enhancing cell numbers by 20-45% at mid-log phase. The order of growth stimulation was ortho > para > meta with respect to the position of the OH group. Both SA and aspirin reduced 16:3 in chloroplast galactolipids. In addition, both compounds inhibited lipoxygenase activity and lowered the levels of lipid hydroperoxides and malondialdehydes in the cells. The present study has demonstrated the possibility of using SA or aspirin to promote algal growth through the manipulation of lipid metabolising enzymes.


Assuntos
Aspirina , Chlamydomonas , Ácido Salicílico , Aspirina/farmacologia , Chlamydomonas/efeitos dos fármacos , Cloroplastos/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Dessaturases/metabolismo , Lipoxigenase/metabolismo , Ácido Salicílico/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-31911359

RESUMO

It is well known that parasitic weeds such as Orobanche (broomrape) significantly decrease crop growth and yield. Although hormonal priming is a well-known inducer of plant resistance against broomrapes (Orobanche spp.), the metabolic events associated with such resistance are poorly understood. Therefore, the current work was undertaken to elucidate the role of SA in inducing tomato resistance against Orobanche, considering its impact on carbon and nitrogen metabolism of the host. Total carbon and nitrogen and levels of carbon (sugars, organic acids and fatty acids) and nitrogen (amino acids and polyamines)-containing metabolites as well as the activities of some key enzymes involved in their metabolic pathways were evaluated. Broomrape infection significantly disrupted C/N ratio in the host roots. On contrary, SA treatment markedly induced accumulation of sugars, organic acids, fatty acids, amino acids as well as polyamines in healthy plants. Under broomrape challenge, SA mitigated the infection-induced growth inhibition by improving the level of nitrogen-containing osmoprotectants (proline, arginine and some polyamines). However, a decrease was observed in some C and N assimilates which are well known to be potentially transferred to the parasite, such as sucrose, asparagine, alanine, serine and glutamate. Interestingly, SA treatment induced the catapolism of polyamines and fatty acids in the host root. Accordingly, our study suggests that SA-induced resistance against broomrape relies on the rational utilization of C and N assimilates in a manner that disturbs the sink strength of the parasite and/or activates the defense pool of the host.


Assuntos
Carbono , Resistência à Doença , Lycopersicon esculentum , Nitrogênio , Orobanche , Ácido Salicílico , Carbono/metabolismo , Resistência à Doença/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/parasitologia , Nitrogênio/metabolismo , Orobanche/fisiologia , Ácido Salicílico/farmacologia
10.
Ecotoxicol Environ Saf ; 191: 110206, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954923

RESUMO

Heat stress is found to be a detrimental factor for growth and development of alfalfa (Medicago sativa L.) which is tremendously invaluable forage due to its high feed value and yield potential. Salicylic acid (SA) has been reported to play a pivotal role in the regulation of plants biotic and abiotic stress response. However, the role of exogenous SA in protecting alfalfa from heat-induced damage has rarely been studied. In this study, four-week-old alfalfa seedlings were treated with 0.25 mM or 0.5 mM SA five days prior to high stress treatment (three day), and various growth and physiological traits were measured. The results showed that exogenous SA pretreatment could improve leaf morphology, plant height, biomass, chlorophyll content, and photosynthetic efficiency of alfalfa under heat stress. Meanwhile, SA could alleviate heat-induced membrane damage by reducing electrolyte leakage (EL) and malondialdehyde (MDA) content, and regulate the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD). The results revealed that exogenous SA application enhanced alfalfa heat tolerance by modulating various morphological and physiological characteristics under heat stress, with more prominent effect at lower concentration (0.25 mM). Overall, this study provides fundamental insights into the SA-mediated physiological adaptation of alfalfa plants to heat stress, which could have useful implication in managing other plants which are suffering global warming.


Assuntos
Resposta ao Choque Térmico/efeitos dos fármacos , Medicago sativa/efeitos dos fármacos , Ácido Salicílico/farmacologia , Antioxidantes/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Malondialdeído/metabolismo , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Peroxidase/metabolismo , Fotossíntese/efeitos dos fármacos , Superóxido Dismutase/metabolismo
11.
Plant Mol Biol ; 102(4-5): 463-475, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916083

RESUMO

The mechanism by which endogenous salicylic acid (SA) regulates leaf senescence remains elusive. Here we provide direct evidence that an enhancement of endogenous SA level, via chemical-induced upregulation of ISOCHORISMATE SYNTHASE 1 (ICS1), could significantly accelerate the senescence process of old leaves through mediation of the key SA signaling component NON EXPRESSOR OF PATHOGENESIS RELATED GENES 1 (NPR1) in Arabidopsis. Importantly, by taking advantage of this chemically induced leaf senescence system, we identified a mitogen-activated protein kinase (MAPK) cascade MKK4/5-MPK1/2 that is required for the SA/NPR1-mediated leaf senescence. Both MKK4/5 and MPK1/2 exhibited SA-induced kinase activities, with MPK1/2 being the immediate targets of MKK4/5. Double mutants of mkk4 mkk5 and mpk1 mpk2 displayed delayed leaf senescence, while constitutive overexpression of the kinase genes led to premature leaf senescence. Such premature leaf senescence was suppressed when they were overexpressed in an SA synthesis defective mutant (sid2) or signaling detective mutant (npr1). We further showed that MPK1, but not MPK2, could directly phosphorylate NPR1. Meanwhile, MPK1 also mediated NPR1 monomerization. Notably, induction of disease resistance was significantly compromised in the single and double mutants of the kinase genes. Taken together, our data demonstrate that the MKK4/5-MPK1/2 cascade plays a critical role in modulating SA signaling through a complex regulatory network in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Regulação da Expressão Gênica de Plantas , Sistema de Sinalização das MAP Quinases , Folhas de Planta/enzimologia , Ácido Salicílico/farmacologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Transdução de Sinais
12.
Environ Sci Pollut Res Int ; 27(2): 1359-1372, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31749001

RESUMO

Triclosan (TCS) is a chlorophenol which is highly bacteriostatic and used in a wide array of consumer products. TCS is now one of the most commonly detected organic pollutants in the sewage sludges. The sludge utilization for fertilizers on agricultural land would pose the risk of causing adverse effects on plant growth and yield by TCS. However, the toxicity of TCS toward plants is comparatively less understood. In this study, we assessed the effects of TCS on tobacco plants which were grown in MS medium or soils containing various concentrations of TCS. Our results indicated that TCS at the concentration of 2 mg/L could strongly inhibit the tobacco seed germination. TCS could suppress tobacco plant growth in soil with different concentrations (10, 20, and 50 mg/kg) of TCS through the downregulation of chlorophyll contents, restricting photosynthesis and increasing generation of reactive oxygen species (ROS). Salicylic acid (SA) plays important roles in the stress response of plants. The role of exogenous SA application in protecting tobacco plants from TCS stress was also investigated in this study. SA application could significantly increase net photosynthesis, enhance antioxidant enzyme activity, and thereby enhancing tobacco plant tolerance to TCS. Moreover, the activation of MPK3 and MPK6 induced by TCS was downregulated in plants with the treatment of SA. It was thus referred that mitogen-activated protein kinases (MAPKs) might play a key role in the signal transduction of TCS stress, and this process might be regulated by SA signaling. Overall, our results demonstrated that TCS had negative impacts on tobacco plants and SA played a protective role on tobacco plants against TCS stress.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Ácido Salicílico/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Triclosan/efeitos adversos , Antioxidantes , Estresse Oxidativo/fisiologia , Fotossíntese/fisiologia , Estresse Fisiológico/fisiologia , Tabaco
13.
Gene ; 727: 144245, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715302

RESUMO

DEK involves in the modulation of cell proliferation, differentiation, apoptosis, migration and cell senescence. However, direct genetic evidence proving the functions of DEK in disease resistance against pathogens is still deficient. In the present study, four DEKs were identified in tomato genome and their roles in disease resistance in tomato were analyzed. The expression levels of DEKs were differently induced by Botrytis cinerea, Pseudomonas syringae pv. tomato (Pst) DC3000 and defense-related signaling molecules (such as jasmonic acid, aethylene precursor and salicylic acid). The DEKs' silencing by virus induced gene silencing led to decreased resistance against B. cinerea or Pst DC3000. The underlying mechanisms may be through the upregulation of the accumulation of reactive oxygen species (ROS) and the changed expression levels of defense-related genes by pathogen inoculation. These results indicate that DEKs involve in disease resistance against different pathogens and thus broaden the knowledge of DEK genes' function in tomato.


Assuntos
Resistência à Doença/genética , Inativação Gênica/efeitos dos fármacos , Lycopersicon esculentum/genética , Botrytis/patogenicidade , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Lycopersicon esculentum/metabolismo , Oxilipinas/farmacologia , Doenças das Plantas/genética , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Pseudomonas syringae/patogenicidade , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Transdução de Sinais/genética , Fatores de Transcrição/genética
14.
Plant Physiol Biochem ; 147: 10-20, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31837556

RESUMO

An experimentation was carried out to appraise whether or not nitric oxide (NO) contributes to salicylic acid (SA)-induced salinity tolerance particularly by regulating ascorbate-glutathione (AsA-GSH) cycle. Before starting salinity stress (SS), SA (0.5 mM) was sprayed to the foliage of plants once every other day for a week and then seedlings were grown under control or SS (100 mM NaCl), for five weeks. Salinity stress enhanced the AsA-GSH cycle-related enzymes, glutathione reductase (GR), ascorbate peroxidase (APX), and dehydroascorbate reductase (DHAR), and monodehydroascorbate reductase (MDHAR). Furthermore, SS caused substantial decreases in plant physiological-related traits such as leaf potassium (K) contents, K+/Na+ ratio, the ratios of reduced ascorbate/dehydroascorbic acid (AsA/DHA) and reduced glutathione/oxidized glutathione (GSH/GSSG), but in contrast, significant increases occurred in leaf hydrogen peroxide, malondialdehyde, electron leakage, proline, the premier antioxidant enzymes' activities, Na+ and NO. SA reduced leaf Na+ content and oxidative stress-related traits, but improved all earlier-mentioned traits compared with those in plants treated with SS alone. All positive effects of SA were eliminated by NO scavenger, 0.1 mM 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1- oxyl-3-oxide (c-PTIO) by reducing NO, suggesting that NO produced by SA up-regulated the activities of AsA-GSH cycle and antioxidant enzymes, so it could play a central function as a signal molecule in salt tolerance of pepper plants.


Assuntos
Capsicum , Óxido Nítrico , Ácido Salicílico , Tolerância ao Sal , Regulação para Cima , Antioxidantes , Ácido Ascórbico/metabolismo , Capsicum/efeitos dos fármacos , Capsicum/genética , Glutationa/metabolismo , Estresse Oxidativo , Ácido Salicílico/farmacologia , Tolerância ao Sal/genética , Plântula/efeitos dos fármacos , Plântula/genética , Regulação para Cima/efeitos dos fármacos
15.
Ecotoxicol Environ Saf ; 188: 109877, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704320

RESUMO

Salinity represents a serious environmental threat to crop production and by extension, to world food supply, social and economic prosperity of the developing world. Salicylic acid (SA) is an endogenous plant signal molecule involved in regulating various plant responses to stress. In the present study, we characterized the regulatory role of exogenous SA for their ability to ameliorate deleterious effects of salt stress (0, 100, 150, 200 mM NaCl) in choysum plants through coordinated induction of antioxidants, ascorbate glutathione (AsA-GSH) cycle, and the glyoxalase enzymes. An increase in salt stress dramatically declined root and shoot growth, leaf chlorophyll and relative water content (RWC), subsequently increased electrolyte leakage (EL) and osmolytes accumulation in choysum plants. Salt stress disrupted the antioxidant and glyoxalase defense systems which persuaded oxidative damages and carbonyl toxicity, indicated by increased H2O2 generation, lipid peroxidation, and methylglyoxal (MG) content. However, application of SA had an additive effect on the growth of salt-affected choysum plants, which enhanced root length, plant biomass, chlorophyll contents, leaf area, and RWC. Moreover, SA application effectively eliminated the oxidative and carbonyl stress by improving AsA and GSH pool, upregulating the activities of antioxidant enzymes and the enzymes associated with AsA-GSH cycle and glyoxalase system. Overall, SA application completely counteracted the salinity-induced deleterious effects of 100 and 150 mM NaCl and partially mediated that of 200 mM NaCl stress. Therefore, we concluded that SA application induced tolerance to salinity stress in choysum plants due to the synchronized increase in activities of enzymatic and non-enzymatic antioxidants, enhanced efficiency of AsA-GSH cycle and the MG detoxification systems.


Assuntos
Ácido Ascórbico/genética , Brassica rapa/efeitos dos fármacos , Brassica rapa/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutationa/genética , Ácido Salicílico/farmacologia , Estresse Salino/efeitos dos fármacos , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Brassica rapa/crescimento & desenvolvimento , Glutationa/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Aldeído Pirúvico/metabolismo
16.
Int J Mol Sci ; 21(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861733

RESUMO

The effects of plant inoculation with plant growth-promoting rhizobacteria (PGPR) and those resulting from the exogenous application of salicylic acid (SA) or methyl jasmonte (MeJA) on total phenolic content (TPC) and monoterpenes in Mentha x piperita plants were investigated. Although the PGPR inoculation response has been studied for many plant species, the combination of PGPR and exogenous phytohormones has not been investigated in aromatic plant species. The exogenous application of SA produced an increase in TPC that, in general, was of a similar level when applied alone as when combined with PGPR. This increase in TPC was correlated with an increase in the activity of the enzyme phenylalanine ammonia lyase (PAL). Also, the application of MeJA at different concentrations in combination with inoculation with PGPR produced an increase in TPC, which was more relevant at 4 mM, with a synergism effect being observed. With respect to the main monoterpene concentrations present in peppermint essential oil (EO), it was observed that SA or MeJA application produced a significant increase similar to that of the combination with rhizobacteria. However, when plants were exposed to 2 mM MeJA and inoculated, an important increase was produced in the concentration on menthol, pulegone, linalool, limonene, and menthone concentrations. Rhizobacteria inoculation, the treatment with SA and MeJA, and the combination of both were found to affect the amount of the main monoterpenes present in the EO of M. piperita. For this reason, the expressions of genes related to the biosynthesis of monoterpene were evaluated, with this expression being positively affected by MeJA application and PGPR inoculation, but was not modified by SA application. Our results demonstrate that MeJA or SA application combined with inoculation with PGPR constitutes an advantageous management practice for improving the production of secondary metabolites from M. piperita.


Assuntos
Mentha piperita/crescimento & desenvolvimento , Monoterpenos/análise , Fenóis/análise , Reguladores de Crescimento de Planta/farmacologia , Rhizobiaceae/fisiologia , Acetatos/farmacologia , Ciclopentanos/farmacologia , Sinergismo Farmacológico , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mentha piperita/química , Mentha piperita/microbiologia , Oxilipinas/farmacologia , Fenilalanina Amônia-Liase/metabolismo , Extratos Vegetais/análise , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Metabolismo Secundário/efeitos dos fármacos
17.
Genes (Basel) ; 11(1)2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31861342

RESUMO

The protease inhibitors (PIs) in plants are involved primarily in defense against pathogens and pests and in response to abiotic stresses. However, information about the PI gene families in tomato (Solanum lycopersicum), one of the most important model plant for crop species, is limited. In this study, in silico analysis identified 55 PI genes and their conserved domains, phylogenetic relationships, and chromosome locations were characterized. According to genetic structure and evolutionary relationships, the PI gene families were divided into seven families. Genome-wide microarray transcription analysis indicated that the expression of SlPI genes can be induced by abiotic (heat, drought, and salt) and biotic (Botrytis cinerea and tomato spotted wilt virus (TSWV)) stresses. In addition, expression analysis using RNA-seq in various tissues and developmental stages revealed that some SlPI genes were highly or preferentially expressed, showing tissue- and developmental stage-specific expression profiles. The expressions of four representative SlPI genes in response to abscisic acid (ABA), salicylic acid (SA), ethylene (Eth), gibberellic acid (GA). and methyl viologen (MV) were determined. Our findings indicated that PI genes may mediate the response of tomato plants to environmental stresses to balance hormone signals. The data obtained here will improve the understanding of the potential function of PI gene and lay a foundation for tomato breeding and transgenic resistance to stresses.


Assuntos
Perfilação da Expressão Gênica/métodos , Lycopersicon esculentum/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/farmacologia , Proteínas Secretadas Inibidoras de Proteinases/genética , Sequenciamento Completo do Genoma/métodos , Ácido Abscísico/farmacologia , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Simulação por Computador , Etilenos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/genética , Família Multigênica , Paraquat/farmacologia , Filogenia , Proteínas de Plantas/genética , Ácido Salicílico/farmacologia , Análise de Sequência de RNA
18.
Int J Mol Sci ; 20(22)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752185

RESUMO

Cadmium (Cd) is one of the prominent environmental hazards, affecting plant productivity and posing human health risks worldwide. Although salicylic acid (SA) and nitric oxide (NO) are known to have stress mitigating roles, little was explored on how they work together against Cd-toxicity in rice. This study evaluated the individual and combined effects of SA and sodium nitroprusside (SNP), a precursor of NO, on Cd-stress tolerance in rice. Results revealed that Cd at toxic concentrations caused rice biomass reduction, which was linked to enhanced accumulation of Cd in roots and leaves, reduced photosynthetic pigment contents, and decreased leaf water status. Cd also potentiated its phytotoxicity by triggering reactive oxygen species (ROS) generation and depleting several non-enzymatic and enzymatic components in rice leaves. In contrast, SA and/or SNP supplementation with Cd resulted in growth recovery, as evidenced by greater biomass content, improved leaf water content, and protection of photosynthetic pigments. These signaling molecules were particularly effective in restricting Cd uptake and accumulation, with the highest effect being observed in "SA + SNP + Cd" plants. SA and/or SNP alleviated Cd-induced oxidative damage by reducing ROS accumulation and malondialdehyde production through the maintenance of ascorbate and glutathione levels, and redox status, as well as the better activities of antioxidant enzymes superoxide dismutase, catalase, glutathione S-transferase, and monodehydroascorbate reductase. Combined effects of SA and SNP were observed to be more prominent in Cd-stress mitigation than the individual effects of SA followed by that of SNP, suggesting that SA and NO in combination more efficiently boosted physiological and biochemical responses to alleviate Cd-toxicity than either SA or NO alone. This finding signifies a cooperative action of SA and NO in mitigating Cd-induced adverse effects in rice, and perhaps in other crop plants.


Assuntos
Cádmio/toxicidade , Nitroprussiato/farmacologia , Oryza/crescimento & desenvolvimento , Ácido Salicílico/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Sinergismo Farmacológico , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Óxido Nítrico/metabolismo , Oryza/efeitos dos fármacos , Oryza/metabolismo , Fotossíntese , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Água/metabolismo
19.
PLoS One ; 14(11): e0224836, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31714906

RESUMO

The opportunistic pathogen Escherichia coli, a common member of the human gut microbiota belonging to the Enterobacteriaceae family, is the causative agent of the majority of urinary tract infections (UTIs). The gut microbiota serves as a reservoir for uropathogenic E. coli where they are shed in feces, colonize the periurethral area, and infect the urinary tract. Currently, front line treatment for UTIs consists of oral antibiotics, but the rise of antibiotic resistance is leading to higher rates of recurrence, and antibiotics cause collateral damage to other members of the gut microbiota. It is commonly believed that incorporation of the American cranberry, Vaccinium macrocarpon, into the diet is useful for reducing recurrence of UTIs. We hypothesized such a benefit might be explained by a prebiotic or antimicrobial effect on the gut microbiota. As such, we tested cranberry extracts and whole cranberry powder on a human gut microbiome-derived community in a gut simulator and found that cranberry components broadly modulate the microbiota by reducing the abundance of Enterobacteriaceae and increasing the abundance of Bacteroidaceae. To identify the specific compounds responsible for this, we tested a panel of compounds isolated from cranberries for activity against E. coli, and found that salicylate exhibited antimicrobial activity against both laboratory E. coli and human UTI E. coli isolates. In a gut simulator, salicylate reduced levels of Enterobacteriaceae and elevated Bacteroidaceae in a dose dependent manner.


Assuntos
Bacteroidaceae/crescimento & desenvolvimento , Enterobacteriaceae/crescimento & desenvolvimento , Microbioma Gastrointestinal , Modelos Biológicos , Extratos Vegetais/farmacologia , Vaccinium macrocarpon/química , Bacteroidaceae/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Hidroxibenzoatos/farmacologia , Testes de Sensibilidade Microbiana , Pós , Ácido Salicílico/farmacologia , Infecções Urinárias/microbiologia
20.
Molecules ; 24(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775347

RESUMO

The inhibitory effect of new chemical entities on rat liver P450 marker activities was investigated in a functional approach towards drug development. Treatment of colorectal cancer (CRC) and chemoprevention using salicylic acid has gained a lot of attention, mainly in the prevention of the onset of colon cancer. Thus, an in vitro inhibitory effect of salicylic acid on rat CYP2C11 activity was examined by using high performance liquid chromatography (HPLC). High performance liquid chromatography analysis of a CYP2C11 assay was developed on a reversed phase C18 column (SUPELCO 25 cm × 4.6 mm × 5 µm) at 243 nm using 32% phosphate buffer (pH 3.36) and 68% methanol as a mobile phase. The CYP2C11 assay showed good linearity for all components (R2 > 0.999). Substrates and metabolites were found to be stable for up to 72 hours. Additionally, the method demonstrated good reproducibility, intra- and inter-day precision (<15%), acceptable recovery and accuracy (80%-120%), and low detection (1.3501 µM and 3.2757 µM) and quantitation limit values (4.914 µM and 9.927 µM) for 16α-hydroxytestosterone and testosterone, respectively. Salicylic acid acts reversibly as a noncompetitive (weak) inhibitor with Ki = 84.582 ± 2.67 µM (concentration of inhibitor to cause 50% inhibition of original enzyme activity (IC50) = 82.70 ± 2.67 µM) for CYP2C11 enzyme activity. This indicates a low potential to cause toxicity and drug-drug interactions.


Assuntos
Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Inibidores das Enzimas do Citocromo P-450/farmacologia , Família 2 do Citocromo P450/antagonistas & inibidores , Fígado/efeitos dos fármacos , Ácido Salicílico/farmacologia , Esteroide 16-alfa-Hidroxilase/antagonistas & inibidores , Animais , Hidrocarboneto de Aril Hidroxilases/química , Catálise , Cromatografia Líquida de Alta Pressão , Inibidores das Enzimas do Citocromo P-450/química , Família 2 do Citocromo P450/química , Desenvolvimento de Medicamentos , Humanos , Fígado/enzimologia , Ratos , Ácido Salicílico/química , Esteroide 16-alfa-Hidroxilase/química
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