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1.
Bull Environ Contam Toxicol ; 105(1): 127-133, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32548730

RESUMO

In this work the toxicity caused by explosive industries effluent (yellow water) at different levels of toxicity (genetic, cellular and organismal level) was evaluated by the Allium cepa test and the Sorghum sudanense germination. The results showed that the effluent paralyze the mitotic process, keeping the cells in the interphase, decreasing the mitotic index in A. cepa. Chromosomal abnormalities such as c-metaphases, adhesions, breaks, early ascending chromosomes and irregular nucleus were observed for this receptor species. The germination of S. sudanense was reduced, and the development of the radicles were affected, showing reduced tolerance index at the highest concentrations of the effluent. Thus, it is concluded that the effluent from the explosive industry is extremely toxic to the tested organisms, both in cellular and chromosomal level and also for seed germination.


Assuntos
Substâncias Explosivas/toxicidade , Germinação/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Aberrações Cromossômicas , Índice Mitótico , Cebolas/genética , Cebolas/fisiologia , Sorghum
2.
J Environ Manage ; 271: 110947, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32579517

RESUMO

Onion is a commonly used vegetable in the Cuyo Region, Argentina, and important in the world global vegetable production ranking. Production levels often exceed immediate markets of fresh sale, and excesses, although still edible, are currently discarded (mostly incinerated and disposed in landfill, creating numerous environmental hazards). To minimize these adverse environmental problems, this research investigates upgrading the discarded products by dehydration, hence guaranteeing their ultimate food-use. The dehydration process of discarded onion cv. Crioula Roxa was hence studied at 60 and 70 °C, temperatures selected to maintain the main physicochemical characteristics of the onions, while also creating optimum heat and mass transfer coefficients while significantly reducing the energy consumption and CO2 emissions. When using an electrically-heated convective dryer, the Specific Energy Consumption (SEC) values and the CO2 emissions during dehydration at 70 °C are 738.89 kWh.kg-1 and 264.74 kg of CO2 kg-1, respectively. These values are only 41.61 kWh.kg-1 and 2-4 kg of CO2 kg-1 if a solar dryer is applied. The thermal diffusivities were 1.86✕10-10 m2 s-1 (dehydration) and 1.08✕10-10 m2 s-1 (rehydration), showing a weak effect of the dehydration process on the solid structure and properties.


Assuntos
Desidratação , Cebolas , Argentina , Alimentos , Temperatura Alta , Humanos
3.
Sci Total Environ ; 737: 139704, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512299

RESUMO

Mycotoxin contamination of food and water is a serious global concern. Aflatoxin B1 (AFB1) is a deadly mycotoxin that contaminates both food and water bodies in the environment. AFB1 is reported to cause severe health issues, including hepatotoxicity, teratogenicity, and immunotoxicity in humans; however, the mechanistic effects on plant and aquatic animals are not fully understood. To obtain a clear understanding of the effects of AFB1 on the ecosystem, we examined the influence of AFB1 exposure on different model systems corresponding to various habitats. In the current study, AFB1 contamination consequences were studied on a human normal cell lines (HaCaT, CCD 841 CoN), meristematic Allium cepa (onion) root cells, and zebrafish embryonic development. Our results clearly indicate that concentrations of AFB1 >10 µM are toxic to HaCaT cells. Morphological changes of HaCaT and CCD 841 CoN cells were clearly observed after exposure to AFB1. Particularly in HaCaT cells, treatment with 50 µM and 100 µM AFB1induces oxidative stress by excessive endogenous free-radical production such as ROS and NO generation. These consequences accelerate the ROS-dependent DNA damage events, which subsequently result in caspase mediated programmed cell death. Exposure of A. cepa root cells to AFB1 for 24 h resulted in abnormal cell division. A. cepa root cells subjected to AFB1 treatment showed a significant concentration-dependent increase in metaphase arrest. Exposure of zebrafish embryos to AFB1 also revealed that AFB1 contamination restricts the larval growth and development, resulting in a remarkably increased zebrafish mortality rate. Collectively, results of the current study indicate that AFB1 contamination triggers the programmed cell death machinery, subsequently affecting the ecosystem.


Assuntos
Aflatoxina B1 , Cebolas , Animais , Apoptose , Caspases , Divisão Celular , Ecossistema , Feminino , Humanos , Larva , Gravidez , Espécies Reativas de Oxigênio , Peixe-Zebra
4.
Allergol. immunopatol ; 48(3): 232-236, mayo-jun. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-192024

RESUMO

BACKGROUND: China and Spain are world leaders in the consumption of edible bulbs (garlic and onion), but there are few references to their capacity to cause allergic symptoms. The target was to study allergic sensitization and clinical symptoms associated with garlic and onion consumption in a large sample of allergic patients. METHODS: An observational cross-sectional study was conducted, testing garlic and onion extracts in 8109 patients of all ages seen by our allergy clinic in 2018. Forty-four aeroallergens and foods were tested, including garlic and onion, with prick test and determination of specific IgE. Oral provocation and contact tests were performed if a delayed reaction was suspected. Western Blot was performed in the serum of patients positive to garlic and onion. RESULTS: We conducted 356,798 skin tests and 4254 specific IgE determinations. Of the 8109 patients tested, 2508 (30.92%) presented with symptoms associated with food intake and, in these patients, food hypersensitivity was detected by skin test, positive specific IgE or provocation in 924 patients, and was caused by garlic or onions in 27, indicating a prevalence of 2.92%. Immunodetection showed an association between the symptoms and a specific LTP to these bulbs, without cross-reactivity with other LTPs in the Mediterranean diet (peach, wheat). CONCLUSIONS: Allergic hypersensitivity to garlic and onions should not be underestimated and, given their high consumption, should be included in the diagnostic food allergy battery


No disponible


Assuntos
Humanos , Masculino , Feminino , Lactente , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Hipersensibilidade Alimentar/diagnóstico , Alho/imunologia , Imunoglobulina E/sangue , Cebolas/imunologia , Hipersensibilidade Alimentar/imunologia , Testes Cutâneos , Teste de Radioalergoadsorção , Estudos Transversais , Western Blotting
5.
PLoS One ; 15(5): e0231753, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369481

RESUMO

Lou onion (Allium fistulosum L. var. viviparum) is an abundant source of flavonols which provides additional health benefits to diseases. Genome-wide specific length amplified fragment (SLAF) sequencing method is a rapidly developed deep sequencing technologies used for selection and identification of genetic loci or markers. This study aimed to elucidate the genetic diversity of 122 onion accessions in China using the SLAF-seq method. A set of 122 onion accessions including 107 A.fistulosum L. var. viviparum Makino, 3 A.fistulosum L. var. gigantum Makino, 3 A.mongolicum Regel and 9 A.cepa L. accessions (3 whites, 3 reds and 3 yellows) from different regions in China were enrolled. Genomic DNA was isolated from young leaves and prepared for the SLAF-seq, which generated a total of 1,387.55 M reads and 162,321 high quality SNPs (integrity >0.5 and MAF >0.05). These SNPs were used for the construction of neighbor-joining phylogenetic tree, in which 10 A.fistulosum L. var. viviparum Makino accessions from Yinchuan (Ningxia province) and Datong (Qinghai province) had close genetic relationship. The 3 A.cepa L. clusters (red, white and yellow) had close genetic relationship especially with the 97 A.fistulosum L. var. viviparum Makino accessions. Population structure analysis suggested entire population could be clustered into 3 groups, while principal component analysis (PCA) showed there were 4 genetic groups. We confirmed the SLAF-seq approach was effective in genetic diversity analysis in red onion accessions. The key findings would provide a reference to the Lou onion germplasm in China.


Assuntos
Cebolas/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma/métodos , China , Mapeamento Cromossômico , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Folhas de Planta/genética , Análise de Componente Principal , Locos de Características Quantitativas
6.
Chemosphere ; 256: 126985, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32445994

RESUMO

Biodegradable mulch films are an alternative to polyethylene films used in agriculture for weed control, improving crop productivity. This change could minimize the residue production and costs related to the final disposal. Nevertheless, the environmental safety of these biodegradable products is scarcely investigated. In this work, samples of poly(butylene adipate-co-terephthalate)-PBAT mulch films, with and without UV stabilizer additives, were prepared. Aqueous extracts of soil samples, where mulch films were disposed, were investigated using bioassays with Lactuca sativa, Allium cepa, and cell culture HepG2/C3A. As PBAT is expected to suffer photodegradation and biodegradation, soil samples mixed with films before and after these processes were evaluated. Soil aqueous extracts promoted root grown (mainly hypocotyl) of L. sativa, probably due to presence of nutrients. So, to evaluate toxicity potential, in this case it was necessary to use aqueous extract prepared with soil instead of ultrapure water as the control. After doing this analysis it was observed that no adverse impacts due to PBAT films occurred. No chromosomal abnormalities were observed in A. cepa bioassay for any of tested samples. The absence of genotoxic potential was confirmed by comet assay and micronucleus test using human hepatocarcinoma cell line HepG2/C3A. These results showed that the soil did not induce damage to the tested organisms, before and after degradation of PBAT films.


Assuntos
Biodegradação Ambiental , Alface/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Adipatos , Agricultura , Alcenos , Ecotoxicologia , Humanos , Alface/fisiologia , Cebolas/fisiologia , Ácidos Ftálicos , Poliésteres/química , Poluentes do Solo
7.
Environ Monit Assess ; 192(6): 360, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32399591

RESUMO

Hospital laundries are responsible for a significant part of the amount of wastewater that is generated in hospitals. Hospital laundry wastewater represents a complex mixture of chemicals that arouse concerns about possible environmental risks. The objective of the present study was to evaluate the cytotoxicity of different laundry effluents from the Regional University Hospital of Maringá, Paraná, Brazil, on Allium cepa L. meristematic root cells. The effluents were characterised as rinsing, wetting, prewashing, washing, softening, wastewater (the effluent generated at the end of the washing process), the wastewater that was treated by physicochemical (PC) processes and the wastewater that was treated by advanced oxidation processes (PC + UV, PC + H2O2 and PC + UV/H2O2). The mitotic indexes were calculated by scoring 5000 cells per group and the statistical analyses were performed by one-way ANOVA, followed by Tukey's post-test (α = 0.05). Results showed that the rinsing, wetting, prewashing and wastewater laundry effluents were cytotoxic at 24 h of exposure, significantly reducing the mitotic index. Despite the slight cytotoxicity of the PC + UV/H2O2 treatment, physicochemical and advanced oxidation processes efficiently reduced the critical parameters of wastewater, such as the biochemical and chemical oxygen demands, to tolerable levels of effluent discharge. It is essential to perform constant monitoring of these effluents in order to reduce the possible occurrence of environmental impacts.


Assuntos
Cebolas , Poluentes Químicos da Água , Brasil , Monitoramento Ambiental , Hospitais , Peróxido de Hidrogênio , Oxirredução , Águas Residuárias
8.
Environ Sci Pollut Res Int ; 27(22): 28066-28076, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32405953

RESUMO

Effects of imidacloprid and iprodione, isolated and in mixture, were assessed by using seed germination and root growth test, flow cytometry, and chromosomal aberrations test on Allium cepa root meristem. The highest concentrations of imidacloprid, including field concentration, increased the frequency of sub-G1 particles, decreased the frequency of nuclei in G2/M, increased the coefficient of variation of G1 (CVG1) and the frequency of aberrant cells, and inhibited the mitotic index culminating in the reduction in root length. All doses of iprodione also presented cytogenotoxic action. The highest concentration of the fungicide affected the growth of A. cepa roots. In response to exposure to pesticide mixtures, the cell cycle of A. cepa was blocked in the G1 phase. The mixtures with low doses of the pesticides significantly decreased the mitotic index, and as a consequence, the genotoxicity was reduced. In the mixtures with the highest doses of the agrochemicals, the blockage of the cell cycle was insufficient for damage repair, resulting in a significant increase of chromosomal aberrations. The results suggest caution in the use of pesticides doses that induce cytological abnormalities in non-target organisms.


Assuntos
Cebolas , Praguicidas , Aminoimidazol Carboxamida/análogos & derivados , Aberrações Cromossômicas , Dano ao DNA , Humanos , Hidantoínas , Meristema , Índice Mitótico , Neonicotinoides , Nitrocompostos , Raízes de Plantas
9.
Pestic Biochem Physiol ; 165: 104553, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359535

RESUMO

Thrips tabaci is a key pest of onions, especially in the Pacific Northwestern USA. Management of T. tabaci is dominated by the application of various insecticides. However, T. tabaci is known to develop insecticide resistance which possibly leads to control failures, crop loss, and environmental concern. Here, we evaluated resistance status of T. tabaci populations from conventional and organic commercial onion fields to three widely used insecticides: oxamyl, methomyl, and abamectin with on-field concentration-mortality bioassays. The biochemistry and molecular mechanisms underlying resistance to these insecticides were also investigated by using enzymatic assays and detecting resistance-associated mutations. Field-evolved resistance to oxamyl, methomyl and abamectin were detected in most of the T. tabaci populations collected from conventional onion farms. At the labeled field rate, all the tested insecticides, particularly methomyl and oxamyl, had significantly reduced efficacy. Enzymatic assays of insecticide target and detoxification enzymes indicated that T. tabaci populations in Western USA onions harbor multiple mechanisms of resistance including enhanced activities of detoxification enzymes and target site insensitivity. Our results provide new information in understanding the dynamics of T. tabaci adaptation to multiple insecticides, which will help to design sustainable insecticide resistance management strategies for T. tabaci. Furthermore, this study provides the foundation for future research in identifying the biochemical and molecular markers associated with insecticide resistance in T. tabaci.


Assuntos
Inseticidas , Tisanópteros , Animais , Resistência a Inseticidas , Metomil , Cebolas
10.
J Environ Sci Health B ; 55(7): 604-612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32274963

RESUMO

A supercritical fluid extraction (SFE) method was presented for the determination of neonicotinoid pesticides in green onion. We optimized the SFE parameters, namely the pressure, temperature, type and concentration of the modifier solvent, and extraction time, by testing on the incurred green onion applied with four commercial neonicotinoid formulations at the harvesting stage. The analytical values of the four neonicotinoids, obtained by 5 min dynamic SFE with a 25% (v/v) methanol/supercritical carbon dioxide mixture at 80 °C and 25 MPa, were in good agreement with those obtained by solid-liquid extraction using a homogenizer. This latter homogenization method is employed as a Japanese official method for the analysis of pesticide residues in food. The SFE-to-homogenization analytical value ratios were in the range 98.8-100.0%. Spike-and-recovery testing with spiked green onion was also performed by optimized SFE. The ratios of the analytical-to-spiked concentrations for six neonicotinoids obtained by the SFE method were 96.1-102.1% for 0.4 mg/kg and 93.9-104.1% for 4.0 mg/kg spiking levels. These values satisfied the Japanese validation guidelines for the testing method of pesticides in food. These results indicate that SFE is applicable for the analysis of neonicotinoids in green onion and enables automatic extraction with a small amount of solvent.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Contaminação de Alimentos/análise , Neonicotinoides/análise , Cebolas/química , Praguicidas/análise , Dióxido de Carbono/química , Análise de Alimentos/métodos , Liofilização , Metanol/química , Resíduos de Praguicidas/análise
11.
Mol Plant Microbe Interact ; 33(5): 718-720, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32237963

RESUMO

Peronospora destructor is an obligate biotrophic oomycete that causes downy mildew on onion (Allium cepa). Onion is an important crop worldwide, but its production is affected by this pathogen. We sequenced the genome of P. destructor using the PacBio sequencing platform, and de novo assembly resulted in 74 contigs with a total contig size of 29.3 Mb and 48.48% GC content. Here, we report the first high-quality genome sequence of P. destructor and its comparison with the genome assemblies of other oomycetes. The genome is a very useful resource to serve as a reference for analysis of P. destructor isolates and for comparative genomic studies of the biotrophic oomycetes.


Assuntos
Cebolas/microbiologia , Peronospora/genética , Doenças das Plantas/microbiologia , Genoma
12.
PLoS One ; 15(4): e0231082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240261

RESUMO

Increased periods of prolonged droughts followed by severe precipitation events are expected throughout South America due to climate change. Freshwater sediments are especially sensitive to these changing climate conditions. The increased oscillation of water levels in aquatic ecosystems causes enhanced cycles of sediment drying and rewetting. Here we experimentally evaluate the effects of induced drought followed by a rewetting event on the release of carbon dioxide (CO2), methane (CH4), nutrients (nitrogen and phosphorus), and trace elements (iron, manganese, and zinc) from the sediment of a tropical reservoir in southeastern Brazil. Furthermore, we used bulb onions (Allium cepa) to assess the potential cytogenotoxicity of the water overlying sediments after rewetting. We found peaks in CO2 and CH4 emissions when sediments first transitioned from wet to dry, with fluxes declining as sediments dried out. CO2 emissions peaked again upon rewetting, whereas CH4 emissions remained unaltered. Our experiment also revealed average increases by up to a factor of ~5000 in the release rates of nutrients and trace elements in water overlying sediments after rewetting. These increased release rates of potentially toxic compounds likely explain the lower replication of Allium cepa cells (up to 22% reduction) exposed to water overlying sediments after rewetting. Our findings suggest that increased events of drought followed by rewetting may lead to a range of changes in freshwater ecosystems, including nutrient enrichment, increased toxicity following resuspension of contaminants, and higher emission of greenhouse gases to the atmosphere.


Assuntos
Dessecação , Sedimentos Geológicos/química , Gases de Efeito Estufa/análise , Mutagênicos/toxicidade , Oligoelementos/análise , Água/química , Dióxido de Carbono/análise , Morte Celular/efeitos dos fármacos , Difusão , Metano/análise , Índice Mitótico , Nitrogênio/análise , Cebolas/citologia , Fósforo/análise
13.
Int J Syst Evol Microbiol ; 70(5): 3018-3026, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32228807

RESUMO

Five Gram-reaction-negative, aerobic, motile with one to three polar flagella, rod-shaped bacterial strains, MAFF 212408T, MAFF 212409, MAFF 212410, MAFF 301498 and MAFF 730085, were isolated from diseased Welsh onion (Allium fistulosum L.) in Japan. Analysis of their 16S rRNA gene sequences showed that they belong to the genus Pseudomonas with the highest similarity to Pseudomonas extremaustralis 14-3T (99.86 %), Pseudomonas antarctica CMS 35T (99.79 %) and Pseudomonas poae DSM 14936T (99.72%). The genomic DNA G+C content was 59.5 mol% and the major fatty acids (>5 %) were summed feature 3, C16 : 0, summed feature 8 and C12 : 0 2-OH. Multilocus sequence analysis using the rpoD, gyrB and rpoB gene sequences and phylogenomic analysis based on the 90 core genes demonstrated that the strains are members of the P. fluorescens subgroup, but are distant from all closely related species. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) analysis confirmed low genomic relatedness to their closest relatives [below the recommended thresholds of 95 % (ANI) and 70 % (dDDH) for prokaryotic species delineation]. The strains were characterized by using API 20NE and Biolog GEN III tests, and inoculation tests in Welsh onion, showing that they are phenotypically differentiated from their closest relatives. Based on the genetic and phenotypic evidence, the strains should be classified as representing a novel species, for which the name Pseudomonas kitaguniensis sp. nov. is proposed. The type strain is MAFF 212408T (=ICMP 23530T).


Assuntos
Cebolas/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Pseudomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Japão , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Environ Sci Pollut Res Int ; 27(16): 20335-20343, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32242316

RESUMO

Imazalil (IMZ), a fungicide containing imidazole group, is extensively used for the prevention and treatment of fungal diseases in plants. Current study was performed to examine cyto-genotoxic potential of IMZ on Allium cepa roots by following Allium ana-telophase and single cell gel electrophoresis (comet) assays. The concentration which reduced the growth of the root tips of IMZ by 50% compared to the negative control group (EC50) was found to be 1 µg/mL by Allium root growth inhibition test. 0.5, 1, and 2 µg/mL concentrations of IMZ were exposed to Allium roots for intervals of 24, 48, 72, and 96 h. 10 µg/mL of methyl methane sulfonate (MMS) and distilled water were used as control groups, both positive and negative. Statistical analysis was performed by using one-way ANOVA with Duncan's multiple comparison tests at p ≤ 0.05 and Pearson correlation test at p = 0.01. IMZ showed cytotoxic effect by statistically decreasing root growth and mitotic index (MI) and also genotoxic effect by statistically increasing chromosomal aberrations (CAs) and DNA damage compared to the negative control group. With these cyto-genotoxic effects, it should be used carefully and further cyto-genotoxic mechanisms should be investigated along with other toxicity tests.


Assuntos
Fungicidas Industriais/farmacologia , Cebolas/genética , Aberrações Cromossômicas , Análise Citogenética , Dano ao DNA , Humanos , Imidazóis/farmacologia , Meristema/efeitos dos fármacos , Índice Mitótico , Raízes de Plantas/efeitos dos fármacos
15.
Chemosphere ; 253: 126675, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278918

RESUMO

The carbamazepine (CBZ) is one of the most frequently detected anticonvulsant drugs in water bodies. Although there are reports of its ecotoxicological effects in the scientific literature, toxicity studies have not focused on establishing the mechanism by which CBZ produces its effect at environmentally relevant concentrations. The objective of this work was to evaluate cyto-genotoxicity and its relationship with oxidative stress produced by carbamazepine in the Allium cepa model. The cytotoxicity and genotoxicity, as well as the biomarkers of oxidative stress were analyzed in the roots of A. cepa, exposed to 1 and 31.36 µg L-1 after 2, 6, 12, 24, 48 and 72 h. The results show that genotoxic capacity of this drug in the roots of A. cepa is related to the generation of oxidative stress, in particular with production of hydroperoxides and oxidized proteins. Also, the cytotoxic effect has a high correlation with DNA damage. The results of the present study clearly indicate that bioassays with sensitive plants such as A. cepa are useful and complementary tools to evaluate the environmental impact of emerging contaminants.


Assuntos
Carbamazepina/toxicidade , Poluentes Ambientais/toxicidade , Cebolas/fisiologia , Allium , Bioensaio , Dano ao DNA , Biomarcadores Ambientais , Cebolas/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Raízes de Plantas/efeitos dos fármacos
16.
Sci Total Environ ; 725: 138387, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32298898

RESUMO

With the exponential growth of nanomaterial production in the last years, nano copper (Cu)-based compounds are gaining more consideration in agriculture since they can work as pesticides or fertilizers. Chinese scallions (Allium fistulosum), which are characterized by their high content of the antioxidant allicin, were the chosen plants for this study. Spectroscopic and microscopic techniques were used to evaluate the nutrient element, allicin content, and enzyme antioxidant properties of scallion plants. Plants were harvested after growing for 80 days at greenhouse conditions in soil amended with CuO particles [nano (nCuO) and bulk (bCuO)] and CuSO4 at 75-600 mg/kg]. Two-photon microscopy images demonstrated the particulate Cu uptake in nCuO and bCuO treated roots. In plants exposed to 150 mg/kg of the Cu-based compounds, root Cu content was higher in plants treated with nCuO compared with bCuO, CuSO4, and control (p ≤ 0.05). At 150 mg/kg, nCuO increased root Ca (86%), root Fe (71%), bulb Ca (74%), and bulb Mg (108%) content, compared with control (p ≤ 0.05). At the same concentration, bCuO reduced root Ca (67%) and root Mg (33%), compared with control (p ≤ 0.05). At all concentrations, nCuO and CuSO4 increased leaf allicin (56-187% and 42-90%, respectively), compared with control (p ≤ 0.05). The antioxidant enzymes were differentially affected by the Cu-based treatments. Overall, the data showed that nCuO enhances nutrient and allicin contents in scallion, which suggests they might be used as a nanofertilizer for onion production.


Assuntos
Allium , Nanopartículas Metálicas , Nanopartículas , Cobre , Nutrientes , Cebolas , Raízes de Plantas , Ácidos Sulfínicos
17.
Chemosphere ; 254: 126716, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32334246

RESUMO

Cyanobacteria are prokaryotes involved in the contamination of aquatic environments since they release toxins that are highly potent and dangerous for living organisms. Prokaryotes produce endo and exotoxins, among others. Exotoxins are highly toxic, while endotoxins have milder toxic effects. The present study evaluated the cytotoxicogenetic potency of both toxins studying them in different concentrations of cyanobacterial biomasses (1 µg/L, 1.5 µg/L, 2 µg/L), to assess the amount of exotoxin present in the cultured medium in which the cyanobacteria were grown. For this evaluation, we used an extract taken from the medium in a concentration of 10%. Our results showed that genotoxic and mutagenic changes in Allium cepa could be observed in all of the varying concentrations of biomass (endotoxin action) and also in the medium induced with exotoxin. Even at low concentrations, these toxins were highly effective at triggering changes in the DNA molecules of organisms exposed to them. This information is highly significant when considering environmental contamination caused by cyanobacteria blooms, since the results of this study show that these toxins may not only kill organisms when found in high concentrations, but also induce mutations when found in low concentrations. Since these mutations are expressed later on in the organisms, it is impossible to associate the observed effect with the event that induced the damage.


Assuntos
Cianobactérias/patogenicidade , Dano ao DNA , Endotoxinas/toxicidade , Exotoxinas/toxicidade , Biomassa , Microcistinas/toxicidade , Mutagênicos/toxicidade , Cebolas/efeitos dos fármacos
18.
Pest Manag Sci ; 76(8): 2720-2725, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170784

RESUMO

BACKGROUND: Onion maggot (Delia antiqua) is a pest of onions worldwide. Current means of managing this pest rely heavily on prophylatic insecticide treatments at planting. These options may not be viable in organic production systems or situations where insecticide-resistant populations occur. Here we explore the efficacy of an attract and kill strategy for control of D. antiqua evaluating the ability of attractive, spinosad containing spheres to kill adult D. antiqua and reduce crop losses. RESULTS: Spinosad containing spheres were able to consistently kill D. antiqua adults over the course of the field season (mortality range: between 49% and 59% on average). Pairing spinosad spheres with Delia Lure increased efficacy by 72% compared with the spheres alone. Performance of this attract and kill strategy also can reduce damage by D. antiqua larvae in the field, but it did not achieve a level of control comparable to the level provided by a conventional insecticide treatment. CONCLUSION: Implementation of this attract and kill strategy could be a valuable tool in situations where conventional pesticides are either not available or desired, where additional control techniques are needed, or to provide a season-long option for control of D. antiqua populations. © 2020 Society of Chemical Industry.


Assuntos
Macrolídeos/farmacologia , Animais , Dípteros , Combinação de Medicamentos , Controle de Insetos , Inseticidas , Larva , Cebolas
19.
PLoS One ; 15(3): e0228485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130211

RESUMO

Fifty four Trichoderma strains were isolated from soil samples collected from garlic and onion crops in eight different sites in Brazil and were identified using phylogenetic analysis based on combined ITS region, tef1-α, cal, act and rpb2 sequences. The genetic variability of the recovered Trichoderma species was analysed by AFLP and their phenotypic variability determined using MALDI-TOF. The strain clusters from both typing techniques coincided with the taxonomic determinations made from phylogenetic analysis. The phylogenetic analysis showed the occurrence of Trichoderma asperellum, Trichoderma asperelloides, Trichoderma afroharzianum, Trichoderma hamatum, Trichoderma lentiforme, Trichoderma koningiopsis, Trichoderma longibrachiatum and Trichoderma erinaceum, in the soil samples. We also identified and describe two new Trichoderma species, both in the harzianum clade of section Pachybasium, which we have named Trichoderma azevedoi sp. nov. and Trichoderma peberdyi sp. nov. The examined strains of both T. azevedoi (three strains) and T. peberdyi (12 strains) display significant genotypic and phenotypic variability, but form monophyletic clades with strong bootstrap and posterior probability support and are morphologically distinct from their respective most closely related species.


Assuntos
Alho/microbiologia , Cebolas/microbiologia , Microbiologia do Solo , Trichoderma/classificação , Trichoderma/isolamento & purificação , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Biodiversidade , Brasil , DNA Fúngico/análise , DNA Fúngico/genética , Técnicas de Tipagem Micológica/métodos , Filogenia , Análise de Sequência de DNA/métodos , Especificidade da Espécie , Trichoderma/citologia , Trichoderma/genética
20.
Environ Sci Pollut Res Int ; 27(14): 17382-17392, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32157539

RESUMO

In this study, the hyperthermophilic dark fermentation of onion wastes (OW) for hydrogen production was investigated. OW were used at different proportions in mixed fruit and vegetable wastes (FVW) to evaluate their effect on hydrogen production by Thermotoga maritima. Fermentations were performed in a pH-controlled batch stirred tank reactor (BSTR) using seawater as a simplified reaction medium. Results showed that increasing OW proportions in total fruit and vegetable wastes (tFVW) improved H2 production. Therefore, increasing the OW to tFVW ratio from 0 to 0.8 increased the cumulative H2 production from 109 to 223.6 mmol/L. The H2 productivity was also improved from 7.3 to 28.82 mmol/h.L. In fact, OW contain carbohydrates, sulfur compounds, and other nutrients, which were used as a carbon source and energetic substrate for H2 production by the halophilic bacterium T. maritima in seawater without additional chemical compounds. Then, a H2 yield of 3.36 mol H2/mol hexose was achieved using 200 mL of OW, containing 55 mmol/L of carbohydrates. A concept of H2 production from FVW at high proportions of OW in a simplified reaction medium was proposed. It allowed a H2 yield of 209 LH2/kg volatile solids which could be an interesting future alternative to the current fossil fuel.


Assuntos
Carbono , Cebolas , Reatores Biológicos , Fermentação , Hidrogênio , Enxofre
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