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1.
J Agric Food Chem ; 68(2): 523-529, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31908169

RESUMO

The present work sought to contribute to the development of new nematicides. Benzaldehydes were initially converted to nitrile oxides that underwent 1,3-dipolar cycloaddition reactions with methyl acrylate to generate 4,5-dihydroisoxazoles. In in vitro tests, methyl 3-phenyl-4,5-dihydroisoxazole-5-carboxylate (1) and methyl 3-(4-chlorophenyl)-4,5-dihydroisoxazole-5-carboxylate (4) increased the mortality of Meloidogyne exigua and Meloidogyne incognita second-stage juveniles (J2). Compounds 1 and 4 presented necessary concentrations of 398 and 501 µg mL-1, respectively, to kill 50% of M. incognita J2 (LC50 values), while the value for carbofuran (positive control) was 168 µg mL-1. In in vivo tests, compounds 1 and 4 reduced the number of M. incognita galls in tomato roots by 70 and 40%, respectively, and the number of eggs by 89 and 44%. Using an in silico approach, we showed that compounds 1 and 4 were toxic to the nematodes by binding to the allosteric binding sites of the agonist-binding domains of the nematode nicotinic acetylcholine receptors. These results opened up possibilities for further investigations aimed at developing novel commercial nematicides.


Assuntos
Antinematódeos/toxicidade , Isoxazóis/toxicidade , Doenças das Plantas/parasitologia , Tylenchoidea/efeitos dos fármacos , Animais , Antinematódeos/química , Simulação por Computador , Proteínas de Helminto/química , Proteínas de Helminto/metabolismo , Isoxazóis/química , Lycopersicon esculentum/parasitologia , Raízes de Plantas/parasitologia , Receptores Nicotínicos/química , Receptores Nicotínicos/metabolismo , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/metabolismo
2.
Microbes Environ ; 35(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-31932539

RESUMO

Diverse members of Bradyrhizobium diazoefficiens, B. japonicum, and B. ottawaense were isolated from the roots of field-grown sorghum plants in Fukushima, and classified into "Rhizobia" with nodulated soybeans, "Free-living diazotrophs", and "Non-diazotrophs" by nitrogen fixation and nodulation assays. Genome analyses revealed that B. ottawaense members possessed genes for N2O reduction, but lacked those for the Type VI secretion system (T6SS). T6SS is a new bacterial weapon against microbial competitors. Since T6SS-possessing B. diazoefficiens and B. japonicum have mainly been isolated from soybean nodules in Japan, T6SS-lacking B. ottawaense members may be a cryptic lineage of soybean bradyrhizobia in Japan.


Assuntos
Biodiversidade , Bradyrhizobium/genética , Oxirredutases/genética , Sorghum/microbiologia , Sistemas de Secreção Tipo VI/deficiência , Bradyrhizobium/classificação , Bradyrhizobium/isolamento & purificação , Variação Genética , Fixação de Nitrogênio/genética , Filogenia , Nodulação/genética , Raízes de Plantas/microbiologia , Rhizobium/classificação , Rhizobium/genética , Rhizobium/isolamento & purificação , Sistemas de Secreção Tipo VI/genética
3.
J Environ Manage ; 256: 109953, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31989980

RESUMO

The study evaluated plants with phytoremediation potential that occur spontaneously in an area of copper mining tailings in Southern of Brazil. Eleven plant species were investigated for heavy metal concentrations in its biomass. All species showed copper concentrations greater than 100 mg kg-1, and seven species highlighted for copper concentrations between 321 and 586 mg kg-1 and these species showed Cr concentrations between 25 and 440 mg kg-1. The species S. viarum Dunal and B. trimera Less were highlighted showing the highest concentrations of Cr (586 mg kg-1) and Cu (440 mg kg-1), respectively. Seven species showed Pb phytoextraction potential and four species showed Cu phytostabilization potential. It was concluded that the investigated species are adapted to low nutritional conditions and showed tolerance to heavy metals, mainly Cu, Pb and Cr in its biomass.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Brasil , Cobre , Mineração , Raízes de Plantas
4.
Microbes Environ ; 35(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-31969532

RESUMO

The pmoA gene, encoding particulate methane monooxygenase in methanotrophs, and nirS and nirK genes, encoding bacterial nitrite reductases, were examined in the root and rhizosphere sediment of three common emergent macrophytes (Phragmites australis, Typha angustifolia, and Scirpus triqueter) and unvegetated sediment from eutrophic Wuliangsuhai Lake in China. Sequencing analyses indicated that 334 out of 351 cloned pmoA sequences were phylogenetically the most closely related to type I methanotrophs (Gammaproteobacteria), and Methylomonas denitrificans-like organisms accounted for 44.4% of the total community. In addition, 244 out of 250 cloned nirS gene sequences belonged to type I methanotrophs, and 31.2% of nirS genes were the most closely related to paddy rice soil clone SP-2-12 in Methylomonas of the total community. Three genera of type I methanotrophs, Methylomonas, Methylobacter, and Methylovulum, were common in both pmoA and nirS clone libraries in each sample. A quantitative PCR (qPCR) analysis demonstrated that the copy numbers of the nirS and nirK genes were significantly higher in rhizosphere sediments than in unvegetated sediments in P. australis and T. angustifolia plants. In the same sample, the nirS gene copy number was significantly higher than that of nirK. Furthermore, type I methanotrophs were localized in the root tissues according to catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH). Thus, nirS-carrying type I methanotrophs were enriched in macrophyte root and rhizosphere sediment and are expected to play important roles in carbon/nitrogen cycles in a eutrophic wetland.


Assuntos
Eutrofização , Gammaproteobacteria/genética , Genes Bacterianos/genética , Magnoliopsida/microbiologia , Microbiologia do Solo , Áreas Alagadas , Proteínas de Bactérias/genética , China , Gammaproteobacteria/classificação , Gammaproteobacteria/metabolismo , Dosagem de Genes , Lagos/microbiologia , Metano/metabolismo , Nitrito Redutases/genética , Oxigenases/genética , Raízes de Plantas/microbiologia , Rizosfera
5.
J Photochem Photobiol B ; 203: 111761, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31896050

RESUMO

The combination of different colors from light-emitting diodes (LEDs) may influence growth and production of secondary metabolites in plants. In the present study, the effect of light quality on morphophysiology and content of 20-hydroxyecdysone (20E), a phytoecdysteroid, was evaluated in accessions of an endangered medicinal species, Pfaffia glomerata, grown in vitro. Two accessions (Ac22 and Ac43) were cultured in vitro under three different ratios of red (R) and blue (B) LEDs: (i) 1R:1B, (ii) 1R:3B, and (iii) 3R:1B. An equal ratio of red and blue light (1R:1B) increased biomass accumulation, anthocyanin content, and 20E production (by 30-40%). Moreover, 1R:1B treatment increased the size of vascular bundles and vessel elements, as well as strengthened xylem lignification and thickening of the cell wall of shoots. The 1R:3B treatment induced the highest photosynthetic and electron transport rates and enhanced the activity of oxidative stress-related enzymes. Total Chl content, Chl/Car ratio, and NPQ varied more by accession type than by light source. Spectral quality affected primary metabolism differently in each accession. Specifically, in Ac22 plants, fructose content was higher under 1R:1B and 1R:3B treatments, whereas starch accumulation was higher under 1R:3B, and sucrose under 3R:1B. In Ac43 plants, sugars were not influenced by light spectral quality, but starch content was higher under 3R:1B conditions. In conclusion, red and blue LEDs enhance biomass and 20E production in P. glomerata grown in vitro.


Assuntos
Amaranthaceae/efeitos da radiação , Ecdisterona/análise , Luz , Amaranthaceae/crescimento & desenvolvimento , Amaranthaceae/metabolismo , Antocianinas/análise , Biomassa , Carotenoides/análise , Catalase/metabolismo , Clorofila/análise , Cromatografia Líquida de Alta Pressão , Folhas de Planta/química , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Caules de Planta/química , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/metabolismo , Plantas Medicinais/efeitos da radiação , Amido/metabolismo , Superóxido Dismutase/metabolismo
6.
Plant Mol Biol ; 102(3): 323-337, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900819

RESUMO

KEY MESSAGE: There is a link between PAP/SAL retrograde pathway, ethylene signaling and Fe metabolism in Arabidopsis. Nuclear gene expression is regulated by a diversity of retrograde signals that travel from organelles to the nucleus in a lineal or classical model. One such signal molecule is 3'-phosphoadenisine-5'-phosphate (PAP) and it's in vivo levels are regulated by SAL1/FRY1, a phosphatase enzyme located in chloroplast and mitochondria. This metabolite inhibits the action of a group of exorribonucleases which participate in post-transcriptional gene expression regulation. Transcriptome analysis of Arabidopsis thaliana mutant plants in PAP-SAL1 pathway revealed that the ferritin genes AtFER1, AtFER3, and AtFER4 are up-regulated. In this work we studied Fe metabolism in three different mutants of the PAP/SAL1 retrograde pathway. Mutant plants showed increased Fe accumulation in roots, shoots and seeds when grown in Fe-sufficient condition, and a constitutive activation of the Strategy I Fe uptake genes. As a consequence, they grew more vigorously than wild type plants in Fe-deficient medium. However, when mutant plants grown in Fe-deficient conditions were sprayed with Fe in their leaves, they were unable to deactivate root Fe uptake. Ethylene synthesis inhibition revert the constitutive Fe uptake phenotype. We propose that there is a link between PAP/SAL pathway, ethylene signaling and Fe metabolism.


Assuntos
Difosfato de Adenosina/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ferro/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Transdução de Sinais , Difosfato de Adenosina/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Clorofila , Cloroplastos/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Homeostase , Mitocôndrias/metabolismo , Mutação , Monoéster Fosfórico Hidrolases/genética , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
7.
World J Microbiol Biotechnol ; 36(2): 26, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31997078

RESUMO

Salinity stress is one of the key constraints for sustainable crop production. It has gained immense importance in the backdrop of climate change induced imbalanced terrestrial water budgets. The traditional agronomic approaches and breeding salt-tolerant genotypes have often proved insufficient to alleviate salinity stress. Newer approaches like the use of bacterial endophytes associated with agricultural crops have occupied center place recently, owing to their advantageous role in improving crop growth, health and yield. Research evidences have revealed that bacterial endophytes can promote plant growth by accelerating availability of mineral nutrients, helping in production of phytohormones, siderophores, and enzymes, and also by activating systemic resistance against insect pest and pathogens in plants. These research developments have opened an innovative boulevard in agriculture for capitalizing bacterial endophytes, single species or consortium, to enhance plant salt tolerance capabilities, and ultimately lead to translational refinement of crop-production business under salty environments. This article reviews the latest research progress on the identification and functional characterization of salt tolerant endophytic bacteria and illustrates various mechanisms triggered by them for plant growth promotion under saline environment.


Assuntos
Bactérias/metabolismo , Endófitos/fisiologia , Desenvolvimento Vegetal/fisiologia , Tolerância ao Sal/fisiologia , Plantas Tolerantes a Sal/microbiologia , Produtos Agrícolas/metabolismo , Produtos Agrícolas/microbiologia , Microbiota , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/microbiologia , Salinidade , Sideróforos/metabolismo , Microbiologia do Solo
8.
J Agric Food Chem ; 68(5): 1480-1493, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31899641

RESUMO

Licorice (Glycyrrhiza uralensis Fisch) possesses a substantial share of the global markets for its unique sweet flavor and diverse pharmacological compounds. Cultivated licorice is widely distributed in northwest regions of China, covered with land with a broad range of salinities. A preliminary study indicated that suitable salt stress significantly increased the content of bioactive constituents in licorice. However, the molecular mechanisms underlying the influence of salinity on the accumulation of these constituents remain unclear, which hinders quality breeding of cultivated licorice. In our study, flavonoid-related structural genes were obtained, and most of them, such as phenylalanine ammonia-lyases, cinnamate 4-hydroxylases, 4-coumarate: CoA ligases, chalcone synthases, chalcone-flavanone isomerase, and flavonol synthase, showed high levels after salt treatment. In the biosynthesis of glycyrrhizin, three key enzymes (bAS, CYP88D6, and CYP72A154) were identified as differentially expressed proteins and remarkably upregulated in the salt-stressed group. Combining these results with the contents of 14 bioactive constituents, we also found that the expression patterns of those structural proteins were logically consistent with changes in bioactive constituent profiles. Thus, we believe that suitable salt stress increased the accumulation of bioactive constituents in licorice by upregulating proteins involved in the related biosynthesis pathways. This work provided valuable proteomic information for unraveling the molecular mechanism of flavonoid and glycyrrhizin metabolism and offered fundamental resources for quality breeding in licorice.


Assuntos
Glycyrrhiza uralensis/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/metabolismo , Cloreto de Sódio/metabolismo , Flavonoides/metabolismo , Glycyrrhiza uralensis/genética , Glycyrrhiza uralensis/metabolismo , Ácido Glicirrízico/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raízes de Plantas/química , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteômica , Estresse Salino
9.
Fitoterapia ; 140: 104434, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760067

RESUMO

Fritillaria cirrhosa bulbus is a Chinese folk herb famous for its antitussive, expectorant, anti-asthma and anti-inflammatory properties, and is widely used to treat respiratory diseases. However, the impacts of F. cirrhosa bulbus on oxidative stress are still unkown. In the present study, we investigated the potential effect and mechanism of six isosteroid alkaloids with different chemical structures from F. cirrhosa bulbus on protection against cigarette smoke-induced oxidative stress in RAW264.7 macrophages. The results showed that six isosteroid alkaloids reduced reactive oxygen species (ROS) production, elevated glutathione (GSH) level and promoted heme oxygenase (HO-1) expression, which is in association with induction of NF-E2-related factor 2 (Nrf2) nuclear translocation and up-regulation of Nrf2 expression. Among these alkaloids, verticinone, verticine, imperialine-3-ß-D-glucoside, delavine and peimisine exhibited more potent effect against CSE-induced oxidative stress than that of imperialine. These findings for the first time demonstrated that F. cirrhosa bulbus may play a protective role in cellular oxidative stress by activating Nrf2-mediated antioxidant pathway. Furthermore, the differences in antioxidant effects of these alkaloids were compared, as well as the corresponding structure-activity relationships were preliminarily elucidated. This suggested that F. cirrhosa bulbus might be a promising therapeutic treatment for the prevent of oxidative stress-related diseases.


Assuntos
Alcaloides/farmacologia , Fritillaria/química , Estresse Oxidativo/efeitos dos fármacos , Fumaça/efeitos adversos , Alcaloides/isolamento & purificação , Animais , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Plantas Medicinais/química , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Produtos do Tabaco
10.
J Photochem Photobiol B ; 202: 111705, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812087

RESUMO

The procurance of gold nanoparticles in the plant extracts is an excellent way to attain nanomaterials natural and eco-friendly nanomaterials. The Dehydrated roots of Chinese Euphorbia fischeriana flowering plant are called "Lang-Du". In this study, the retrieving of gold nanoparticles from Euphorbia fischeriana root was amalgamated by standard procedure. Fabricated gold nanoparticles were portrayed through the investigations of ultraviolet and visible spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FTIR), High resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The UV-Vis and FTIR results explicated the obtained particles were sphere-shaped and the terpenoids of Euphorbia fischeriana had strong communications with gold surface. The HRTEM and XRD images exposed the produced gold nanoparticles had an extreme composition of crystal arrangement and excellent uniformed size of particles. In our study, the Isoprenaline induced myocardial damage established the elevation in TBARS, LOOH of heart tissues and notable decline in antioxidant enzymes SOD, CAT, GPx, and GSH. This biochemical result was additionally proved by histopathological assessment. Remarkably, the pretreatment with EF-AuNps(50 mg/kg b.w) illustrated stabilized levels of serum creatine and cardiotropins in myocardial infarcted animals. And further we understood the essential function of NF-ƙB, TNF-α, IL-6 signaling molecules and its way progression in the development of vascular tenderness.


Assuntos
Euphorbia/química , Ouro/química , Nanopartículas Metálicas/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Animais , Antioxidantes/química , Catalase/genética , Catalase/metabolismo , Creatina Quinase/sangue , Citocinas/metabolismo , Euphorbia/metabolismo , Química Verde , Isoproterenol/toxicidade , Nanopartículas Metálicas/química , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , ATPase Trocadora de Sódio-Potássio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
11.
Plant Dis ; 104(1): 246-254, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31644390

RESUMO

Species within clade 2 of the Fusarium solani species complex (FSSC) are significant pathogens of dry bean (Phaseolus vulgaris) and soybean (Glycine max), causing root rot and/or sudden death syndrome (SDS). These species are morphologically difficult to distinguish and often require molecular tools for proper diagnosis to a species level. Here, a TaqMan probe-based quantitative PCR (qPCR) assay was developed to distinguish Fusarium brasiliense from other closely related species within clade 2 of the FSSC. The assay displays high specificity against close relatives and high sensitivity, with a detection limit of 100 fg. This assay was able to detect F. brasiliense from purified mycelia, infected dry bean roots, and soil samples throughout Michigan. When multiplexed with an existing qPCR assay specific to Fusarium virguliforme, accurate quantification of both F. brasiliense and F. virguliforme was obtained, which can facilitate accurate diagnoses and identify coinfections with a single reaction. The assay is compatible with multiple qPCR thermal cycling platforms and will be helpful in providing accurate detection of F. brasiliense. Management of root rot and SDS pathogens in clade 2 of the FSSC is challenging and must be done proactively, because no midseason management strategies currently exist. However, accurate detection can facilitate management decisions for subsequent growing seasons to successfully manage these pathogens.


Assuntos
Fusarium , Doenças das Plantas , Reação em Cadeia da Polimerase , Soja , Fusarium/genética , Michigan , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Microbiologia do Solo , Soja/microbiologia , Especificidade da Espécie
12.
Plant Dis ; 104(1): 116-120, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31644392

RESUMO

Clubroot, caused by Plasmodiophora brassicae, is an important disease on canola in Alberta, Canada. The pathogen is grouped into pathotypes according to their virulence reaction on differential hosts. Multiple pathotypes or strains are known exist in one field, one plant, or even one gall. This study was conducted with the objective of testing the prevalence of the coexistence of multiple strains in a single gall. In all, 79 canola clubroot galls were collected from 22 fields across Northern Alberta in 2018. Genomic DNA extracted from these single galls was analyzed using RNase H-dependent PCR (rhPCR). The rhPCR primers were designed to amplify a partial sequence of a dimorphic gene, with one primer pair specific to one sequence and the other primer pair specific to the alternative sequence. The amplification of both sequences from DNA obtained from a single gall would indicate that it contains two different P. brassicae strains. The rhPCR analyses indicated that the P. brassicae populations in 50 of the 79 galls consisted of more than one strain. This result emphasizes the need for cautious interpretation of results when a single-gall population is subject to pathotyping or being used as inoculum in plant pathology research. It also confirms that the maintenance of pathotype diversity within single root galls is a common occurrence which has implications for the durability, and stewardship, of single-gene host resistance.


Assuntos
Brassica napus , Plasmodioforídeos , Alberta , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Tumores de Planta/microbiologia , Plasmodioforídeos/classificação , Plasmodioforídeos/genética , Plasmodioforídeos/patogenicidade , Virulência
13.
J Sci Food Agric ; 100(3): 1064-1071, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31713870

RESUMO

BACKGROUND: Glucosinolates (GSLs) are secondary metabolites, mainly existing in Brassica vegetables. Their breakdown products have health benefits and contribute to the distinctive taste of these vegetables. Because of their high value, there is a lot of interest in developing breeding strategies to increase the content of beneficial GSLs in Brassica species. GSLs are synthesized from certain amino acids and their biological roles depend largely on the structure of their side chains. Flavin-containing monooxygenase (FMOGS-OX ) genes are involved in the synthesis of these side chains. To better understand GSL biosynthesis, we sequenced the transcriptomes of turnip (Brassica rapa var. rapa) tubers at four developmental stages (S1-S4) and determined their GSL content. RESULTS: The total GSL content was high at the early stage (S1) of tuber development and increased up to S3, then decreased at S4. We detected 61 differentially expressed genes, including five FMOGS-OX genes, that were related for GSL biosynthesis among the four developmental stages. Most of these genes were highly expressed at stages S1 to S3, but their expression was much lower at S4. We estimated the effect of the five FMOGS-OX genes on GSL content by overexpressing them in turnip hairy roots and found that the amount of aliphatic GSLs increased significantly in the transgenic plants. CONCLUSION: The transcriptome data and characterization of genes involved in GSL biosynthesis, particularly the FMOGS-OX genes, will be valuable for improving the yield of beneficial GSLs in turnip and other Brassica crops. © 2019 Society of Chemical Industry.


Assuntos
Brassica rapa/enzimologia , Brassica rapa/crescimento & desenvolvimento , Glucosinolatos/biossíntese , Oxigenases de Função Mista/metabolismo , Proteínas de Plantas/metabolismo , Vias Biossintéticas , Brassica rapa/genética , Brassica rapa/metabolismo , Dinitrocresóis/metabolismo , Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista/genética , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Transcriptoma
14.
Arch Microbiol ; 202(1): 1-16, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31552478

RESUMO

The acerbic elevation of toxic metal ions in arable lands, enhance the risk of their accumulation and biomagnification in crops as well as in humans. Phytoremediation is an eco-friendly approach to clear metal-contaminated lands by making use of metal accumulation potential of plants; which are referred to as hyperaccumulators. This phytoremediation potential can be enhanced with the symbiotic association between the root of hyperaccumulators and arbuscular mycorrhizae. Modification of root morphology, enhancement of antioxidants biosynthesis, and the increase in shoot biomass are the changes observed in plants as a result of indirect influence of arbuscular mycorrhizae. Direct influence of arbuscular mycorrhizae on enhancing metal tolerance of plants includes immobilization strategies, adsorption of metals on to the hyphal wall and glomalin exudation. Furthermore, we have discussed arbuscular mycorrhizal induced increment in the metal tolerance potential of plants through the alteration in various metabolic processes with special emphasis to the phenylpropanoid pathway.


Assuntos
Biodegradação Ambiental , Metais/toxicidade , Micorrizas/metabolismo , Raízes de Plantas/microbiologia , Plantas/efeitos dos fármacos , Plantas/microbiologia , Simbiose/fisiologia , Biomassa , Poluentes do Solo/toxicidade
15.
Arch Microbiol ; 202(1): 143-151, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31535159

RESUMO

A gram-stain-negative, aerobic, non-spore-forming, rod-shaped, non-motile bacterium strain R4HLG17T was isolated from Tamarix ramosissima roots growing in Kumtag desert. The strain grew at salinities of 0-16% (w/v) NaCl (optimum 5-6%), pH 5-9 (optimum 7) and at 16-45 °C. Based on 16S rRNA gene sequence similarity, strain R4HLG17T belonged to the family Halomonadaceae and was most closely related to Halomonas lutea DSM 23508T(95.1%), followed by Halotalea alkalilenta AW-7T(94.8%), Salinicola acroporae S4-41T(94.8%), Salinicola halophilus CG4.1T(94.6%), and Larsenimonas salina M1-18T(94.4%). Multilocus sequence analysis (MLSA) based on the partial sequences of 16S rRNA, atpA, gyrB, rpoD, and secA genes indicated that the strain R4HLG17T formed an independent and monophyletic branch related to other genera of Halomonadaceae, supporting its placement as a new genus in this family. The draft genome of strain R4HLG17T was 3.6 Mb with a total G + C content of 55.1%. The average nucleotide identity to Halomonas lutea DSM 23508T was 83.5%. Q-9 was detected as the major respiratory quinone and summed feature 8 (C18:1ω7c/C18:1ω6c), summed feature 3 (C16:1ω7c/C16:1ω6c), and C16:0 as predominant cellular fatty acids. On the basis of chemotaxonomic, phylogenetic, and phenotypic evidence, strain R4HLG17T is concluded to represent a novel species of a new genus within Halomonadaceae, for which the name Phytohalomonas tamaricis gen. nov., sp. nov., is proposed. The type strain is R4HLG17T (=ACCC 19929T=KCTC 52415T).


Assuntos
Halomonadaceae/classificação , Raízes de Plantas/microbiologia , Tamaricaceae/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Clima Desértico , Ácidos Graxos/análise , Halomonadaceae/química , Halomonadaceae/genética , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
16.
J Agric Food Chem ; 68(1): 67-76, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31710472

RESUMO

Nanoparticles (NPs) are known to significantly alter plant metabolism in a dose-dependent manner, with effects ranging from stimulation to toxicity. The metabolic adjustment and ionomic balance of bean (Phaseolus vulgaris L.) roots and leaves gained from plants grown in a solid medium added with relatively low dosages (0, 25, 50, and 100 mg/L) of CeO2 NPs were investigated. Ce accumulated in the roots (up to 287.91 mg/kg dry weight) and translocated to the aerial parts (up to 2.78% at the highest CeO2 dosage), and ionomic analysis showed that CeO2 NPs interfered with potassium, molybdenum, and zinc. Unsupervised hierarchical clustering analysis from metabolomic profiles suggested a dose-dependent and tissue-specific metabolic reprogramming induced by NPs. The majority of differential metabolites belonged to flavonoids and other phenolics, nitrogen-containing low molecules (such as alkaloids and glucosinolates), lipids, and amino acids.


Assuntos
Cério/farmacologia , Phaseolus/efeitos dos fármacos , Metabolismo Secundário/efeitos dos fármacos , Aminoácidos/análise , Aminoácidos/metabolismo , Cério/análise , Flavonoides/análise , Flavonoides/metabolismo , Nanopartículas/análise , Phaseolus/química , Phaseolus/metabolismo , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo
17.
J Chem Ecol ; 46(1): 63-75, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832894

RESUMO

Plants experience seasonal fluctuations in abiotic and biotic factors such as herbivore attack rates. If and how root defense expression co-varies with seasonal fluctuations in abiotic factors and root herbivore attack rates is not well understood. Here, we evaluated seasonal changes in defensive root latex chemistry of Taraxacum officinale plants in the field and correlated the changes with seasonal fluctuations in abiotic factors and damage potential by Melolontha melolontha, a major natural enemy of T. officinale. We then explored the causality and consequences of these relationships under controlled conditions. The concentration of the defensive sesquiterpene lactone taraxinic acid ß-D glucopyranosyl ester (TA-G) varied substantially over the year and was most strongly correlated to mean monthly temperature. Both temperature and TA-G levels were correlated with annual fluctuations in potential M. melolontha damage. Under controlled conditions, plants grown under high temperature produced more TA-G and were less attractive for M. melolontha. However, temperature-dependent M. melolontha feeding preferences were not significantly altered in TA-G deficient transgenic lines. Our results suggest that fluctuations in temperature leads to variation in the production of a root defensive metabolites that co-varies with expected attack of a major root herbivore. Temperature-dependent herbivore preference, however, is likely to be modulated by other phenotypic alterations.


Assuntos
Besouros/fisiologia , Glucosídeos/metabolismo , Lactonas/metabolismo , Sesquiterpenos/metabolismo , Taraxacum/química , Animais , Biomassa , Besouros/crescimento & desenvolvimento , Glucosídeos/química , Glucosídeos/farmacologia , Herbivoria/efeitos dos fármacos , Lactonas/química , Lactonas/farmacologia , Larva/efeitos dos fármacos , Larva/fisiologia , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/parasitologia , Estações do Ano , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Taraxacum/metabolismo , Taraxacum/parasitologia , Temperatura Ambiente
18.
Int J Phytoremediation ; 22(2): 134-139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31379204

RESUMO

In this study, different soil Pb concentrations [24 (control), 80, 136, 362, and 1150 mg kg-1] were used to analyze the tolerance threshold and accumulation potential of Brassica juncea L. in a pot experiment under greenhouse conditions. In addition to growth and Pb accumulation, the following contamination indices were calculated: transfer coefficient (TC), translocation factor (TF), and tolerance index (TI). Growth and Pb accumulation were determined at 60 days after emergence. The Pb concentrations were determined using the flame atomic absorption spectrometry (FAAS). The plant height was affected by soil Pb contamination, and it decreased from 1.37 to 0.83 m when the soil Pb concentration increased from 24 (control) to 1150 mg kg-1, respectively. The Pb concentration in the shoots and roots increased as the Pb concentration in the soil increased, reaching 94 mg kg-1 in shoots and 783 mg kg-1 in roots when was grown under 1150 mg kg-1 of Pb. TF was <1 at all levels of contamination. The TI values suggested that B. juncea presented Pb tolerance in Pb contaminated soils. Our findings indicate that B. juncea has the potential to accumulate Pb in soil under tropical conditions.


Assuntos
Mostardeira , Poluentes do Solo , Biodegradação Ambiental , Chumbo , Raízes de Plantas , Brotos de Planta
19.
Chemosphere ; 240: 124916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563104

RESUMO

Cadmium contamination in greenhouse vegetable fields greatly limited the sustainable production especially of leafy vegetables. Hydroxyapatite (HAP), as a common soil amendment, has been widely used in the remediation of Cd-contaminated soils, while its remediation efficiency greatly depends on its particle sizes. In this study, a rhizobag pot experiment was conducted to investigate the effects of HAP (<60 nm, <12 µm and <80 µm) on bioavailability of Cd to celery grown in acidic and slightly Cd-contaminated greenhouse soil. The results suggested that HAP with the largest particle size (<80 µm) had the best effectiveness in reducing Cd uptake especially by the edible part of celery. Specifically, the increase in HAP (<80 µm) addition from 0.5% to 3% prominently reduced Cd concentrations in celery shoot by 19.6%-76.8% as compared with the untreated group. Also, adding HAP (<80 µm) especially at 3% significantly decreased translocation factor (TF) of Cd from celery root to shoot by 30.6% and reduced bioconcentration factor (BCF) of Cd from rhizosphere soil to celery shoot by 76.4%. These were predominantly associated with the significantly increased soil pH and the subsequently decreased soil CaCl2-Cd concentration after adding HAP (<80 µm). Overall, although rhizosphere soil pH was the key factor in controlling Cd uptake by edible celery and regulating BCF and TF of Cd, insignificant root-induced acidification had limited effect on the immobilization efficiency of Cd by HAP (<80 µm). In conclusion, HAP (<80 µm) has good potential for the remediation of Cd-contaminated greenhouse soils.


Assuntos
Apium/efeitos dos fármacos , Apium/metabolismo , Cádmio/farmacocinética , Durapatita/farmacologia , Poluentes do Solo/farmacocinética , Solo/química , Apium/crescimento & desenvolvimento , Biodegradação Ambiental , Disponibilidade Biológica , Cádmio/análise , Durapatita/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Rizosfera , Poluentes do Solo/análise
20.
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
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