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1.
J Agric Food Chem ; 68(7): 1986-1997, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31986044

RESUMO

In this study, the impact of cerium oxide nanoparticles on the nutritional value of tomato (Solanum lycopersicum) fruit grown in soil infested with Fusarium oxysporum f. sp. lycopersici was investigated in a greenhouse pot study. Three-week old seedlings of Bonny Best tomato plants were exposed by foliar and soil routes to nanoparticle CeO2 (NP CeO2) and cerium acetate (CeAc) at 0, 50, and 250 mg/L and transplanted into pots containing a soil mixture infested with the Fusarium wilt pathogen. Fruit biomass, water content, diameter, and nutritional content (lycopene, reducing and total sugar) along with elemental composition, including Ce, were evaluated. Fruit Ce concentration was below the detection limit in all treatments. Foliar exposure to NP CeO2 at 250 increased the fruit dry weight (67%) and lycopene content (9%) in infested plants, compared with the infested untreated control. Foliar exposure to CeAc at 50 mg/L reduced fruit fresh weight (46%) and water content (46%) and increased the fruit lycopene content by 11% via root exposure as compared with the untreated infested control. At 250 mg/L, CeAc increased fruit dry weight (94%), compared with the infested untreated control. Total sugar content decreased in fruits of infested plants exposed via roots to NP CeO2 at 50 mg/kg (63%) and 250 mg/kg (54%), CeAc at 50 mg/kg (46%), and foliarly at 50 mg/L (50%) and 250 mg/L (50%), all compared with the infested untreated control. Plants grown in Fusarium-infested soil had decreased fruit dry weight (42%) and lycopene content (17%) and increased total sugar (60%) and Ca content (140%), when compared with the noninfested untreated control (p ≤ 0.05). Overall, the data suggested minimal negative effects of NP CeO2 on the nutritional value of tomato fruit while simultaneously suppressing Fusarium wilt disease.


Assuntos
Cério/farmacologia , Frutas/química , Fungicidas Industriais/farmacologia , Fusarium/fisiologia , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Fusarium/efeitos dos fármacos , Lycopersicon esculentum/química , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Nanopartículas/química , Valor Nutritivo , Solo/química , Microbiologia do Solo
2.
Food Microbiol ; 87: 103391, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948632

RESUMO

In the present study, we investigated whether cold plasma activation affected the efficacy of aerosolized hydrogen peroxide against S. Typhimurium and L. innocua. Stem scars and smooth surfaces of grape tomatoes, surfaces of Granny Smith apples and Romaine lettuce (both midrib and upper leaves) and cantaloupe rinds were inoculated with two-strain cocktails of S. Typhimurium and 3-strain cocktails of L. innocua. The inoculated samples were treated with 7.8% aerosolized H2O2 with and without cold plasma for various times. For all fresh produce items and surfaces, cold plasma significantly (P < 0.05) improved the efficacy of aerosolized H2O2 against Salmonella and L. innocua. Without cold plasma activation, H2O2 aerosols only reduced populations of Salmonella by 1.54-3.17 log CFU/piece while H2O2 with cold plasma achieved 2.35-5.50 log CFU/piece reductions of Salmonella. L. innocua was more sensitive to the cold plasma-activated H2O2 than Salmonella. Cold plasma activated H2O2 aerosols reduced Listeria populations by more than 5 log CFU/piece on all types and surfaces of fresh produce except for the tomato stem scar area. Without cold plasma, the reductions by H2O2 were only 1.35-3.77 log CFU/piece. Overall, our results demonstrated that cold plasma activation significantly enhanced the efficacy of H2O2 mist against bacteria on fresh produce.


Assuntos
Cucumis melo/microbiologia , Peróxido de Hidrogênio/farmacologia , Alface/microbiologia , Lycopersicon esculentum/efeitos dos fármacos , Malus/microbiologia , Gases em Plasma/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Vitis/microbiologia , Peróxido de Hidrogênio/química , Lycopersicon esculentum/crescimento & desenvolvimento , Salmonella typhimurium/crescimento & desenvolvimento
3.
Chem Biodivers ; 17(1): e1900508, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692228

RESUMO

This study aimed to identify the main components of an essential oil produced from leaves of Ambrosia trifida and to evaluate its potential allelopathic effect on seed germination and seedling growth of lettuce, watermelon, cucumber and tomato. The essential oil was obtained by hydrodistillation and characterized chemically by gas chromatography (GC) coupled with both mass spectrometry (MS) and flame ionization detector (FID). Total 69 compounds were identified, with limonene (20.7 %), bornyl acetate (15.0 %), borneol (14.7 %) and germacrene D (11.6 %) as the major components. The working solutions of the essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at four concentration levels (0.01, 0.1, 0.5 % and 1 %, v/v). The results obtained showed that increase in essential oil concentration leads to decrease in seed germination, as well as shoot and radical length of lettuce, watermelon, cucumber and tomato. The obtained data revealed a highly significant effect (p<0.05) between control and 1 % and 0.5 % oil concentrations in all treatments. The essential oil of A. trifida exhibited more powerful phytotoxic effects on lettuce, watermelon and tomato than on cucumber regarding germination and early seedling growth.


Assuntos
Ambrosia/química , Citrullus/efeitos dos fármacos , Cucumis sativus/efeitos dos fármacos , Alface/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Óleos Voláteis/toxicidade , Folhas de Planta/química , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação
4.
Plant Biol (Stuttg) ; 22(1): 47-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31498556

RESUMO

Tropospheric ozone (O3 ) is considered a major air pollutant having negative effects on plant growth and productivity. Background concentrations are expected to rise in several regions of the world in the next 50 years, affecting plant responses to diseases, thus requiring new management strategies for food production. The effects of elevated O3 on the severity of a bacterial disease, and the effectiveness of a chemical defence inducer, were examined in two cultivars of tomato, Roma and Moneymaker, which present different tolerance to this pollutant. The two cultivars differ in their ability to produce and accumulate reactive oxygen species (ROS) in leaf tissues. Tomato plants were challenged with a strain of Xanthomonas vesicatoria, Xv9, which is pathogenic on tomato. Ozone consistently increased severity of the disease by over 40% in both cultivars. In the more tolerant cultivar, O3 pollution increased disease intensity, even after applying a commercially available product to enhance resistance (acibenzolar-S-methyl, BTH). In the more susceptible cultivar, level of disease attained depended on the oxidative balance that resulted from other stress factors. The antioxidant capacity of the plant at the time of infection was relevant for controlling development of the disease. Our results suggest that development of O3 tolerance in commercial crops might impose a penalty cost in terms of disease management under projected higher O3 concentrations.


Assuntos
Interações Hospedeiro-Patógeno , Lycopersicon esculentum , Ozônio , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/microbiologia , Ozônio/toxicidade , Doenças das Plantas/prevenção & controle , Folhas de Planta/microbiologia
5.
Food Chem ; 311: 126009, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31887558

RESUMO

Proteomics and metabolomics were used to study the changes in proteins and metabolites in tomato fruits at different ripening stages and the effect of salt treatment on fruit quality. The results showed 2607 and 153 differentially expressed proteins in ripe fruits compared with mature green fruits and in NaCl-treated ripe fruits compared with control ripe fruits, respectively. KEGG analysis indicated that these proteins were mainly involved in photosynthesis, pentose and glucuronate interconversions in different ripening stages of fruits, and salt-induced proteins were involved in flavonoid biosynthesis and linoleic acid metabolism. A series of metabolites, including carbohydrates and amino acids showed significantly different accumulations between ripe and mature green fruits and between salt-treated and control fruits. Combined analysis explored glycine, L-alanine, D-xylose and sucrose and some proteins involved in multiple metabolic pathways under salt conditions. Their interactions might affect fruit development and fruit quality under salt treatment.


Assuntos
Lycopersicon esculentum/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Metabolômica , Proteômica , Cloreto de Sódio/farmacologia , Aminoácidos/metabolismo , Ácidos Graxos/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Proteínas de Plantas/metabolismo
6.
Chemosphere ; 240: 124944, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726591

RESUMO

The present study explores the potential of two chromium tolerant and plant growth promoting bacterial strains, Klebsiella sp. and Enterobacter sp. in luxuriant growth of tomato plants under chromium stress conditions. For the assessment of potentiality of the two selected strains, a pot scale experiment was setup with tomato plant under different levels of chromium contamination. In pot experiment, different plant growth parameters, oxidative stress tolerance and chromium bioremediation potential were studied upon inoculation of the selected bacterial strains. The results of pot experiment showed that both the strains were effective in promotion of plant growth and enhanced the plant biomass but Enterobacter sp. was more prominent in enhancement of root length, shoot length, fresh and dry weight, and nutrient uptake in tomato plant. The enhancement of enzymes to combat oxidative stress in tomato plant under chromium stress was also observed for both the strains. Both strains enhanced the levels of superoxide dismutase, catalase, peroxidase, total phenolic, and ascorbic acid in tomato plant under different levels of chromium stress conditions. The chromium phytoremediation potential of tomato plant upon inoculation of both the strains was also studied. The results of phytoremediation showed greater chromium accumulation in roots with poor translocation in shoot upon inoculation of Klebsiella sp. while no significant enhancement in chromium uptake by tomato plant was observed on inoculation of Enterobacter sp. compared to control. Thus, these two strains can effectively be used in luxuriant growth of tomato plant under metal stress conditions.


Assuntos
Cromo/toxicidade , Enterobacter/fisiologia , Klebsiella/fisiologia , Lycopersicon esculentum/fisiologia , Poluentes do Solo/toxicidade , Biodegradação Ambiental , Biomassa , Catalase/metabolismo , Enterobacter/metabolismo , Klebsiella/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/microbiologia , Estresse Oxidativo , Desenvolvimento Vegetal , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo
7.
J Sci Food Agric ; 100(2): 732-743, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31597201

RESUMO

BACKGROUND: Using water with high salinity for plant fertigation may have detrimental effects on plant development and total yield and on the quality of the crop produced. As a possible means to alleviate the negative effects of salinity, silicon (Si) can be incorporated in the nutrient solution supplied to plants. In the present study, hydroponically grown tomato (Solanum lycopersicum Mill.) plants were subjected to two different salinity levels (0 and 50 mmol L-1 NaCl) with and without the application of Si (0 and 2 mmol L-1 K2 SiO3 ) in order to evaluate its possible positive impact on mitigation of salinity stress-induced symptoms. An additional experiment was implemented with postharvest Si application (sodium silicate) to investigate effects on the shelf-life of tomato fruit. RESULTS: Salinity (50 mmol L-1 NaCl) decreased plant size, total yield and fresh fruit weight while a high percentage of blossom end rot symptoms of tomato fruit was also observed. The application of Si in the nutrient solution counteracted these detrimental effects, generating a higher yield and healthier fruit (lower blossom end rot incidence) compared to the untreated plants (no application of Si). Salinity improved several quality-related traits in tomato fruit, resulting in higher marketability, whereas the addition of Si (pre- and postharvest) maintained fruit firmness following storage thereby increasing the shelf-life of tomato fruit. CONCLUSIONS: These findings indicate that Si application (pre- and postharvest) could provide an effective means of alleviating the unfavorable effects of using low-quality water in plant fertigation on tomato plant development, fruit yield and post-harvest quality, through increased fruit firmness. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Frutas/química , Lycopersicon esculentum/efeitos dos fármacos , Silício/farmacologia , Cloreto de Sódio/farmacologia , Flores , Frutas/efeitos dos fármacos , Frutas/metabolismo , Hidroponia , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Salinidade
8.
Food Chem ; 309: 125711, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31699561

RESUMO

A field experiment was set up to evaluate persistence behaviour of pyridalyl in tomato, cabbage and cultivated field soil over two consecutive seasons. An analytical method was developed to analyze pyridalyl residues in different matrices and duly validated, based on single laboratory method validation criteria. Pyridalyl residues were detected and quantified using a gas chromatograph equipped with an electron capture detector. The compound exhibited low persistence in tomato, cabbage and soil. A safe waiting period of 17-18 d after final insecticide application needs to be maintained before harvesting the crop. Both dietary and soil ecological risk were assessed and it was found that the harvested vegetables were toxicologically safe for consumption. However, there was concern about insecticidal toxicity against the algal population of soil which needs to be reconfirmed by further studies.


Assuntos
Brassica/química , Cromatografia Gasosa/métodos , Inseticidas/análise , Lycopersicon esculentum/química , Éteres Fenílicos/análise , Brassica/efeitos dos fármacos , Brassica/metabolismo , Inseticidas/farmacologia , Limite de Detecção , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Éteres Fenílicos/farmacologia , Reprodutibilidade dos Testes , Medição de Risco , Solo/química , Poluentes do Solo/análise
9.
Ecotoxicol Environ Saf ; 186: 109747, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31634660

RESUMO

Cadmium (Cd) contamination has generated an environmental problem worldwide, leading to harmful effects on human health and damages to plant metabolism. Selenium (Se) is non essential for plants, however it can improve plant growth and reduce the adverse effects of abiotic stress. In addition, ethylene may interplay the positive effects of Se in plants. In order to investigate the role of ethylene in Se-modulation of antioxidant defence system in response to Cd-stress, we tested the hormonal mutant Epinastic (epi) with a subset of constitutive activation of the ethylene response and Micro-Tom (MT) plants. For this purpose, Se mineral uptake, Cd and Se concentrations, pigments, malondialdeyde (MDA) and hydrogen peroxide (H2O2) contents, ethylene production, glutathione (GSH) compound, and superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GSH-Px) activities were analysed in MT and epi plants submitted to 0.5 mM CdCl2 and 1 µM of selenate or selenite. MT plants treated with both Se forms increased growth in the presence or not of 0.5 mM CdCl2, but not change epi growth. Both Se forms reduced Cd uptake in MT plants and cause reverse effect in epi plants. P, Mg, S, K and Zn uptake increased in epi plants with Se application, irrespective to Cd exposure. Chlorophylls and carotenoids contents decreased in both genotypes under Cd exposure, in contrast to what was observed in epi leaves in the presence of Se. When antioxidant enzymes activities were concerned, Se application increased Mn-SOD, Fe-SOD and APX activities. In the presence of Cd, MT and epi plants exhibited decreased SOD activity and increased CAT, APX and GR activities. MT and epi plants with Se supply exhibited increased APX and GR activities in the presence of Cd. Overall, these results suggest that ethylene may be involved in Se induced-defence responses, that triggers a positive response of the antioxidant system and improve growth under Cd stress. These results showed integrative roles of ethylene and Se in regulating the cell responses to stressful-conditions and, the cross-tolerance to stress could be used to manipulate ethylene regulated gene expression to induce heavy metal tolerance.


Assuntos
Antioxidantes/metabolismo , Cádmio/efeitos adversos , Etilenos/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Adaptação Fisiológica , Ascorbato Peroxidases/metabolismo , Cádmio/metabolismo , Catalase/metabolismo , Exposição Ambiental , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Lycopersicon esculentum/metabolismo , Mutação , Oxirredução , Folhas de Planta/metabolismo , Ácido Selênico/farmacologia , Ácido Selenioso/farmacologia , Selênio/metabolismo , Superóxido Dismutase/metabolismo
10.
Plant Physiol Biochem ; 143: 203-211, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31518851

RESUMO

Agrobiotechnology challenges involve the generation of new sustainable bioactives with emerging properties as plant biostimulants with reduced environment impact. We analyzed the potential use of recently developed chitosan microparticles (CS-MP) as growth promoters of tomato which constitutes one of the most consumed vegetable crops worldwide. Treatments of tomato seeds with CS-MP improved germination and vigor index. In addition, CS-MP sustained application triggered an improvement in root and shoot biomass reinforcing tomato performance before transplanting. The level of reactive oxygen species (ROS), antioxidant enzyme activities and defense protein markers were modulated by CS-MP treatment in tomato plantlets. Analyses of ARR5:GUS and DR5:GUS transgenic reporter tomato lines highlighted the participation of cytokinin and auxin signaling pathways during tomato root promotion mediated by CS-MP. Our findings claim a high commercial potential of CS-MP to be incorporated as a sustainable input for tomato production.


Assuntos
Quitosana/química , Quitosana/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Biomassa , Citocininas/metabolismo , Ácidos Indolacéticos/metabolismo , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
11.
Ecotoxicology ; 28(9): 1046-1055, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502144

RESUMO

This study aimed to investigate the mode of action of cadmium (Cd) toxicity at cell level, especially at early stages of plant exposure. Tomato seedlings were cultivated in growth media containing from 0.1 to 70 µM CdCl2 for 24 h. Mitotic index, chromosome abnormality, DNA integrity and organization of tubulin-based structures were assessed in root cells. As higher the Cd concentration in the growth media, higher was the DNA damage intensity and the occurrence of chromosomal abnormalities that included chromosome lost, bridges, stickiness, C-metaphase and polyploidy. The profile of chromosomal aberrations also varied with elevated Cd concentration, being observed increases in the frequency of chromosome stickiness. The mitotic index was reduced at the lowest Cd concentration, but such reduction was statistically similar to that detected at the highest concentration, suggesting that mitotic depression is a rapid outcome and, at same time, a Cd-induced effect that is limited at the first 24 h of direct root exposure to this metal. Under exposure to 20 µM CdCl2, heterogenous distribution of the spindle fibers, formation of two spindle complexes in both of the cell poles, absence of centrosome center, polarization of the spindle fibers during cell division, and non-uniform tubulin deposition in microtubule and phragmoplast were noticed. The results indicate that the tubulin-dependent components of cytoskeleton are Cd targets, and the sensitivity of tubulin-based structures to Cd exposure depends on cell cycle phase. Moreover, DNA damage intensity and chromosomal abnormality profile can be employed as markers of Cd toxicity level.


Assuntos
Cádmio/toxicidade , Ciclo Celular/efeitos dos fármacos , Instabilidade Cromossômica/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Poluentes do Solo/toxicidade , Plântula/efeitos dos fármacos
12.
Environ Pollut ; 255(Pt 1): 113141, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541834

RESUMO

In this study, we investigated the physiological and photochemical influences of nanoTiO2 exposure on tomato plants (Lycopersicum esculentum Mill.). Tomato plants were exposed to 100 mg L-1 of nanoTiO2 for 90 days in a hydroponic system. Light irradiances of 135 and 550 µmolphoton m-2 s-1 were applied as environmental stressors that could affect uptake of nanoTiO2. To quantify nanoTiO2 accumulation in plant bodies and roots, we used transmission electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, and X-ray powder diffraction. Phenotypic and physiological influences such as color change, growth rate, fruit productivity, pigment concentration, and enzyme activity (SOD, CAT, APX) were monitored. We observed numerous effects caused by high irradiance and nanoTiO2 exposure, such as rapid chlorophyll decrease, increased anthocyanin and carotenoid concentrations, high enzymatic activity, and an approximately eight-fold increase in fruit production. Moreover, light absorption in the nanoTiO2-treated tomato plants, as measured by a ultraviolet-visible light spectrometer, increased by a factor of approximately 19, likely due to natural pigments that worked as sensitizers, and this resulted in an ∼120% increase in photochemical activities on A, ФPSII, ФCO2, gsw, and E.


Assuntos
Poluentes Ambientais/toxicidade , Lycopersicon esculentum/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Carotenoides/metabolismo , Clorofila/metabolismo , Poluentes Ambientais/análise , Frutas/crescimento & desenvolvimento , Hidroponia , Luz , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/efeitos da radiação , Nanopartículas Metálicas/análise , Raízes de Plantas/metabolismo , Titânio/análise
13.
Chemosphere ; 237: 124458, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31376696

RESUMO

Grape pomace (GP) from Vitis labrusca, the main byproduct from "American table wine" production, is recalcitrant to degradation, and its accumulation is a serious problem with negative environmental impacts. In this work, transformation of grape pomace using a steam pretreatment followed by incubation of GP during a 90-day period with six different fungi were evaluated. Several fungi tested reduced the phytotoxicity of water-soluble fraction (WSFd) from steam-pretreated GP after 90 days' incubation to lettuce and tomato seeds. U. botrytis caused the largest effective phytotoxicity reduction of WSFd (used in the concentration range of 10-1.25% p/v) and was the only fungus causing the removal of monoaromatic compounds. Therefore, this procedure with U. botrytis effectively reduces the availability of phytotoxic monoaromatic compounds in GP, which opens a way for the development of guidelines for the management of these wastes and their potential use as organic amendments in agricultural soil.


Assuntos
Ascomicetos/metabolismo , Indústria Alimentícia , Vitis , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Germinação/efeitos dos fármacos , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Aromáticos/metabolismo , Resíduos Industriais , Alface/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Sementes/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Testes de Toxicidade/métodos , Vinho
14.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438533

RESUMO

Nanotechnology represents an opportunity to improve the use of elements in agriculture. Selenium is an element that is beneficial to plants and essential to the human diet. The size of nanoparticles gives them characteristics that can enhance the benefits that selenium provides to plants. The objective of the present study was to determine the effects of selenium nanoparticles on the growth, antioxidant responses, and fruit quality of tomato developed under NaCl stress. Four doses of selenium nanoparticles (1, 5, 10, and 20 mg L-1) under NaCl stress, only NaCl, and a control were evaluated. The results showed that the impact of salinity on the growth of the tomato crop can be reduced with the application of selenium nanoparticles. However, the amount of both enzymatic and non-enzymatic compounds significantly increased in the leaves and fruits of tomato. The results suggest that the application of selenium nanoparticles generated a positive effect against salinity in the tomato crop; moreover, it had a positive impact on the content of beneficial biocompounds for human health in tomato fruits.


Assuntos
Antioxidantes/química , Frutas/química , Lycopersicon esculentum/química , Nanopartículas/química , Selênio/química , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Frutas/efeitos dos fármacos , Humanos , Licopeno/química , Lycopersicon esculentum/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Superóxido Dismutase/metabolismo , beta Caroteno/química
15.
Molecules ; 24(17)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461965

RESUMO

ß-glucans, heterogeneous glucose polymers present in many organisms, have the capability to activate the innate immune system. Efficacy of activation depends on purity of the compound, molecular structure, polymerization degree, and source. One of the purest forms of crystallized ß-(1-3)-glucan present in nature is the paramylon extracted from the WZSL non-chloroplastic mutant of Euglena gracilis, which can be processed to produce linear nanofibers capable of interacting with specific receptors present on cell membranes. The effects of these nanofibers, already investigated on plants, animals, and humans, will be analyzed.


Assuntos
Euglena gracilis/genética , Glucanos/química , Fatores Imunológicos/química , Mutação , Animais , Artemia/efeitos dos fármacos , Artemia/crescimento & desenvolvimento , Secas , Euglena gracilis/química , Glucanos/farmacologia , Humanos , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/imunologia , Camundongos , Estrutura Molecular , Nanofibras , Multimerização Proteica , Proteínas de Protozoários/genética
16.
Ecotoxicol Environ Saf ; 182: 109410, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284122

RESUMO

Cerium oxide nanoparticles (nanoceria) were synthesized by a novel, simple green chemistry procedure using Elaeagnus angustifolia leaf extract as a reducing and capping agent. The crystalline nature of nanoceria was confirmed by XRD analysis. FTIR analysis revealed that phytochemicals are present on the surface of nanoceria. SEM and TEM images revealed that the nanoceria are well dispersed, spherical in shape with a particle size range in between 30 and 75 nm. Thereafter, the effects of various concentrations of cerium oxide (CeO2) and green synthesized nanoceria on growth and metabolism of Solanum lycopersicum (tomato) were investigated. The bio-accumulation of Ce in tomato seedlings was found to be dose dependent and the results showed that with the increase in exposure concentrations, the accumulation of Ce contents in both root and shoots augmented. However, unlike nanoceria treated seedlings, Ce contents in the roots with CeO2 treatments were negligible than that in the shoots at lower concentrations and this suggested the immobilization of Ce in CeO2 treatment at lower concentrations. Nanoceria at 500 and 1000 mg/L resulted in inhibitory effect on growth of test plant as compared to CeO2 component. The exposure of plants to nanoceria and CeO2 has resulted in significant reduction in pigment content, increased LP, EL and H2O2 content. The activities of antioxidant enzymes viz. SOD, CAT, APX and GPX were significantly up regulated on exposure of nanoceria and CeO2. It is concluded that plant exposure with nanoceria at concentrations of 20 and 100 mg/L were more beneficial for growth and metabolism of tomato plants than that of CeO2 at equivalent concentrations.


Assuntos
Antioxidantes/metabolismo , Cério/farmacologia , Química Verde/métodos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/enzimologia , Nanopartículas/química , Transporte Biológico , Cério/química , Cério/metabolismo , Elaeagnaceae/química , Peróxido de Hidrogênio/metabolismo , Tamanho da Partícula , Extratos Vegetais/química
17.
Int J Mol Sci ; 20(13)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284415

RESUMO

Seedling overgrowth always develops in undernourished plants due to biotic or abiotic stresses, which significantly decrease the yield of crops and vegetables. It is known that the plant growth retardants paclobutrazol (PBZ) and chlormequat chloride (CCC) are the most commonly used chemicals in controlling seedling height in plants by regulating the gibberellin (GA) biosynthesis pathway. However, the exact molecular regulation mechanism remains largely unknown. This study performed a comprehensive transcriptome profile to identify significantly differentially expressed genes after adding CCC and PBZ to the water culture seedling raising system for the first time. According to the obviously restrained shoots and roots, the GA biosynthesis genes were significantly decreased, as well as the endogenous GA content being reduced. Intriguingly, the GA signaling pathway genes were affected in opposite ways, increasing in roots but decreasing in shoots, especially regarding the phytochrome interacting factor SlPIF1 and the downstream genes expansins (SlEXPs), which promote cell wall remodeling. Further study found that the most down-regulated genes SlEXPA5 and SlEXPA15 were expressed specifically in shoot tissue, performing the function of repressing elongation, while the up-regulated genes SlEXPB2 and SlEXPB8 were proven to be root-specific expressed genes, which may promote horizontal elongation in roots. This research reported the comprehensive transcriptome profiling of plant growth retardants in controlling seedling overgrowth and restraining GA biosynthesis through the regulation of the GA signaling-related genes SlPIF1 and SlEXPs, with an opposite expression pattern between roots and shoots.


Assuntos
Desenvolvimento Vegetal/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Transcriptoma/genética , Clormequat/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Giberelinas/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Desenvolvimento Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Plântula/anatomia & histologia , Plântula/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Triazóis/farmacologia
18.
Molecules ; 24(13)2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31284667

RESUMO

Salinity stress limited the production in over 30% of irrigated crops and 7% of dryland agriculture worldwide. The objective was to evaluate the effects of NaCl-stress on the enzymatic activity in tomato. Two experiments were carried out in germination and early vegetative growth stages. The activity of proline and peroxidase of eight varieties (Missouri, Yaqui, Vita, Feroz, Rio Grande, Tropic, Ace, and Floradade) submitted to NaCl concentrations (0, 50, 100, 150 and 200 mM de NaCl) and the semi-quantitative activity of 19 enzymes APY ZYM® were measured under a completely randomized design with four replications. Data were analyzed using univariate-multivariate analysis of variance, Tukey's HSD (p = 0.05), canonical discriminant and cluster analysis. The results showed significant differences between varieties and NaCl in proline content. Proline increased as the NaCl concentration increased. Peroxidase did no show significant differences. Eight enzymes were included within the model to properly classify the varieties and NaCl. In shoots, varieties and NaCl showed that enzymatic activity was higher in the order of alkaline-phosphatase > leucine arylamidase > acid phosphatase > naphthol-AS-BI-phosphohydrolase > n-acetyl-ß-glucosaminidase > ß-galactosidase, while in roots was higher in the order of alkaline-phosphatase > naphthol-AS-BI-phosphohydrolase > acid phosphatase > n-acetyl-ß-glucosaminidase. Acid and alkali phosphatase, lipase, esterase, ß-galactosidase, and trypsin can be a potential biomarker for NaCl-stress tolerance in tomato.


Assuntos
Esterases/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/fisiologia , N-Glicosil Hidrolases/metabolismo , Peptídeo Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Tolerância ao Sal , Cloreto de Sódio/farmacologia , Biomarcadores , Análise por Conglomerados , Ativação Enzimática , Brotos de Planta/fisiologia , Prolina/metabolismo , Proteoma , Proteômica , Plântula/fisiologia
19.
Plant Physiol Biochem ; 142: 84-93, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31277045

RESUMO

S-nitrosylation, regulated by S-nitrosoglutathione reductase (GSNOR), is considered as an important route for nitric oxide (NO)-modulated stress tolerance in plants. However, genetic evidence for the GSNOR-mediated integrated regulation of S-nitrosylation and plant stress response remains elusive until now. In the present study, we used a site-specific nitrosoproteomic approach to identify 334 endogenously S-nitrosylated proteins with 425 S-nitrosylated sites from the wild type (WT) and GSNOR-knockdown (G) tomato plants under both control (C) and sodic alkaline stress (S) conditions. In detail, the results revealed 68, 92, 54 and 56 up-regulated, as well as 10, 36, 14 and 10 down-regulated S-nitrosylated proteins in G-C/WT-C, G-S/WT-S, WT-S/WT-C, and G-S/G-C, which is the first dataset for S-nitrosylated proteins in Solanaceae. These S-nitrosylated proteins are involved in a wide range of various metabolic, cellular and catalytic processes. Based on this data, proteins involving in NO homeostasis control, signaling of Ca2+, ethylene and MAPK, reactive oxygen species (ROS) scavenging, osmotic regulation, as well as energy support pathway have been identified and selected as the key and sensitive targets that were regulated by GSNOR-modulated S-nitrosylation in response to sodic alkaline stress. Taken together, GSNOR is actively involved in the regulation of sodic alkaline stress tolerance by S-nitrosylation. And the present study provided valuable resources and new clues for the study of S-nitrosylation-regulated metabolism in tomato plants.


Assuntos
Aldeído Oxirredutases/metabolismo , Lycopersicon esculentum/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico/fisiologia , Aldeído Oxirredutases/genética , Técnicas de Silenciamento de Genes , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/fisiologia , Óxido Nítrico/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteômica/métodos , Interferência de RNA , Reprodutibilidade dos Testes , Bicarbonato de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos
20.
BMC Plant Biol ; 19(1): 323, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319801

RESUMO

BACKGROUND: Exogenous 5-aminolevulinic acid (ALA) positively regulates plants chlorophyll synthesis and protects them against environmental stresses, although the protection mechanism is not fully clear. Here, we explored the effects of ALA on chlorophyll synthesis in tomato plants, which are sensitive to low temperature. We also examined the roles of the glutathione S-transferase (GSTU43) gene, which is involved in ALA-induced tolerance to oxidation stress and regulation of chlorophyll synthesis under low temperature. RESULTS: Exogenous ALA alleviated low temperature caused chlorophyll synthesis obstacle of uroporphyrinogen III (UROIII) conversion to protoporphyrin IX (Proto IX), and enhanced the production of chlorophyll and its precursors, including endogenous ALA, Proto IX, Mg-protoporphyrin IX (Mg-proto IX), and protochlorophyll (Pchl), under low temperature in tomato leaves. However, ALA did not regulate chlorophyll synthesis at the level of transcription. Notably, ALA up-regulated the GSTU43 gene and protein expression and increased GST activity. Silencing of GSTU43 with virus-induced gene silencing reduced the activities of GST, superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase, and increased the membrane lipid peroxidation; while fed with ALA significant increased all these antioxidase activities and antioxidant contents, and alleviated the membrane damage. CONCLUSIONS: ALA triggered GST activity encoded by GSTU43, and increased tomato tolerance to low temperature-induced oxidative stress, perhaps with the assistance of ascorbate- and/or a glutathione-regenerating cycles, and actively regulated the plant redox homeostasis. This latter effect reduced the degree of membrane lipid peroxidation, which was essential for the coordinated synthesis of chlorophyll.


Assuntos
Ácido Aminolevulínico/metabolismo , Clorofila/metabolismo , Genes de Plantas/fisiologia , Glutationa Transferase/metabolismo , Lycopersicon esculentum/genética , Proteínas de Plantas/metabolismo , Ácido Aminolevulínico/farmacologia , Resposta ao Choque Frio , Glutationa Transferase/genética , Homeostase/efeitos dos fármacos , Peroxidação de Lipídeos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/fisiologia , Oxirredução/efeitos dos fármacos , Proteínas de Plantas/genética
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