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1.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445145

RESUMO

The main goal of growing plants under various photoperiods is to optimize photosynthesis for using the effect of day length that often acts on plants in combination with biotic and/or abiotic stresses. In this study, Brassica juncea plants were grown under four different day-length regimes, namely., 8 h day/16 h night, 12 h day/12 h night, 16 h day/8 h night, and continuous light, and were infected with a necrotrophic fungus Alternaria brassicicola. The development of necroses on B. juncea leaves was strongly influenced by leaf position and day length. The largest necroses were formed on plants grown under a 16 h day/8 h night photoperiod at 72 h post-inoculation (hpi). The implemented day-length regimes had a great impact on leaf morphology in response to A. brassicicola infection. They also influenced the chlorophyll and carotenoid contents and photosynthesis efficiency. Both the 1st (the oldest) and 3rd infected leaves showed significantly higher minimal fluorescence (F0) compared to the control leaves. Significantly lower values of other investigated chlorophyll a fluorescence parameters, e.g., maximum quantum yield of photosystem II (Fv/Fm) and non-photochemical quenching (NPQ), were observed in both infected leaves compared to the control, especially at 72 hpi. The oldest infected leaf, of approximately 30% of the B. juncea plants, grown under long-day and continuous light conditions showed a 'green island' phenotype in the form of a green ring surrounding an area of necrosis at 48 hpi. This phenomenon was also reflected in changes in the chloroplast's ultrastructure and accelerated senescence (yellowing) in the form of expanding chlorosis. Further research should investigate the mechanism and physiological aspects of 'green islands' formation in this pathosystem.


Assuntos
Alternaria/patogenicidade , Mostardeira/microbiologia , Mostardeira/fisiologia , Necrose/microbiologia , Necrose/patologia , Fotossíntese/fisiologia , Doenças das Plantas/microbiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Fluorescência , Mostardeira/metabolismo , Necrose/metabolismo , Fotoperíodo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
2.
Plant Physiol Biochem ; 166: 985-998, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34265697

RESUMO

Effect of triacontanol on drought-induced stress was studied in Brassica juncea L. Foliage of sixteen-days-old plants was sprayed with concentrations (0, 10, 20 and 30 µM) of triacontanol (TRIA) for 7 days. Subsequently, plants were subjected to drought stress (10% polyethylene glycol, PEG6000) for 7 days. Drought stress increased oxidative stress (TBARS, O2●- and H2O2), however, their contents were reduced by TRIA. Total soluble sugars, reduced glutathione, and proline content in stressed plants were increased by TRIA. Activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), and phenylalanine ammonia-lyase (PAL) activity were significantly increased in a dose-dependent manner with TRIA. Potassium (K+) level declined, while magnesium (Mg2+) and calcium (Ca2+) contents increased. The elevated level of lignin under drought with TRIA was significantly associated with MYB46 and PAL gene expression patterns. Altogether, our results suggest that foliar spray of 20 µM TRIA was more operative in reducing the negative impact of drought stress in B. juncea by regulating the antioxidant system, calcium, and lignification.


Assuntos
Antioxidantes , Mostardeira , Ascorbato Peroxidases/metabolismo , Cálcio , Catalase/metabolismo , Secas , Álcoois Graxos , Peróxido de Hidrogênio , Mostardeira/genética , Mostardeira/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo
3.
Int J Mol Sci ; 22(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34281271

RESUMO

The allotetraploid species Brassica juncea (mustard) is grown worldwide as oilseed and vegetable crops; the yellow seed-color trait is particularly important for oilseed crops. Here, to examine the factors affecting seed coat color, we performed a metabolic and transcriptomic analysis of yellow- and dark-seeded B. juncea seeds. In this study, we identified 236 compounds, including 31 phenolic acids, 47 flavonoids, 17 glucosinolates, 38 lipids, 69 other hydroxycinnamic acid compounds, and 34 novel unknown compounds. Of these, 36 compounds (especially epicatechin and its derivatives) accumulated significantly different levels during the development of yellow- and dark-seeded B. juncea. In addition, the transcript levels of BjuDFR, BjuANS,BjuBAN, BjuTT8, and BjuTT19 were closely associated with changes to epicatechin and its derivatives during seed development, implicating this pathway in the seed coat color determinant in B. juncea. Furthermore, we found numerous variations of sequences in the TT8A genes that may be associated with the stability of seed coat color in B. rapa, B. napus, and B. juncea, which might have undergone functional differentiation during polyploidization in the Brassica species. The results provide valuable information for understanding the accumulation of metabolites in the seed coat color of B. juncea and lay a foundation for exploring the underlying mechanism.


Assuntos
Mostardeira/genética , Mostardeira/metabolismo , Catequina/análogos & derivados , Catequina/metabolismo , Flavonoides/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glucosinolatos/metabolismo , Metaboloma , Mostardeira/crescimento & desenvolvimento , Fenótipo , Pigmentação/genética , Sementes/genética , Sementes/metabolismo
4.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209216

RESUMO

Dead organs enclosing embryos, such as seed coats and pericarps, are emerging as important maternally-derived components of the dispersal unit that affect seed performance and fate. In the face of climate change and increased incidents of heatwaves, we sought to investigate the effect of salinity (S), short episodes of high temperature (HS), and combination of S + HS (SHS), at the reproductive phase, on the properties of dead pericarps of Brassica juncea. Proteome and metabolome analyses revealed multiple proteins and metabolites stored in dead pericarps whose levels and composition were altered under single and combined stress conditions. The protein profile of SHS showed a higher correlation with salt than with HS indicating the dominant effect of salt over heat stress. On the other hand, the analysis of metabolites showed that the profile of SHS has better correlation with HS than with salt. The integration of metabolic and proteomic data showed that changes in TCA cycle intermediates and certain amino acids (e.g., proline) under salt treatments (S and SHS) are highly correlated with changes in proteins involved in their biosynthetic pathways. Thus, accumulation of proteins and metabolites in dead pericarps is differently affected by single and combination of salt and heat stresses. Salinity appears to dominate plant response to combined stresses at the protein level, while heat appears to be the major factor affecting metabolite accumulation in dead pericarps.


Assuntos
Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico , Mostardeira/metabolismo , Pressão Osmótica , Proteínas de Plantas/biossíntese
5.
Theor Appl Genet ; 134(10): 3167-3181, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34269830

RESUMO

KEY MESSAGE: Disomic alien chromosome addition Brassica carinata lines with super-high erucic acid content were developed through interspecific hybridization with B. juncea and characterized using molecular, cytological and biochemical techniques. Brassica carinata [A.] Braun (BBCC, 2n = 34) is a climate-resilient oilseed. Its seed oil is high in erucic acid (> 40%), rendering it well suited for the production of biofuel and other bio-based applications. To enhance the competitiveness of B. carinata with high erucic B. napus (HEAR), lines with super-high erucic acid content were developed through interspecific hybridization. To this end, a fad2B null allele from Brassica juncea (AABB, 2n = 36) was introgressed into B. carinata, resulting in a B. carinata fad2B mutant with erucic acid levels of over 50%. Subsequently, the FAE allele from B. rapa spp. yellow sarson (AA, 2n = 20) was transferred to the fad2B B. carinata line, yielding lines with erucic acid contents of up to 57.9%. Molecular analysis using the Brassica 90 K Illumina Infinium™ SNP genotyping array identified these lines as disomic alien chromosome addition lines, with two extra A08 chromosomes containing the BrFAE gene. The alien chromosomes from B. rapa were clearly distinguished by molecular cytogenetics in one of the addition lines. Analysis of microspore-derived offspring and hybrids from crosses with a CMS B. carinata line showed that the transfer rate of the A08 chromosome into male gametes was over 98%, resulting in almost completely stable transmission of an A08 chromosome copy into the progeny. The increase in erucic acid levels was accompanied by changes in the proportions of other fatty acids depending on the genetic changes that were introduced in the interspecific hybrids, providing valuable insights into erucic acid metabolism in Brassica.


Assuntos
Brassica napus/metabolismo , Cromossomos de Plantas/genética , Ácidos Erúcicos/metabolismo , Hibridização Genética , Mostardeira/metabolismo , Fenótipo , Proteínas de Plantas/metabolismo , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Mapeamento Cromossômico/métodos , Ácidos Erúcicos/análise , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Mostardeira/genética , Mostardeira/crescimento & desenvolvimento , Proteínas de Plantas/genética
6.
BMC Plant Biol ; 21(1): 301, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187365

RESUMO

BACKGROUND: Mustard (Brassica juncea) is an important economic vegetable, and some cultivars have purple leaves and accumulate more anthocyanins than the green. The genetic and evolution of purple trait in mustard has not been well studied. RESULT: In this study, free-hand sections and metabolomics showed that the purple leaves of mustard accumulated more anthocyanins than green ones. The gene controlling purple leaves in mustard, Mustard Purple Leaves (MPL), was genetically mapped and a MYB113-like homolog was identified as the candidate gene. We identified three alleles of the MYB113-like gene, BjMYB113a from a purple cultivar, BjMYB113b and BjMYB113c from green cultivars. A total of 45 single nucleotide polymorphisms (SNPs) and 8 InDels were found between the promoter sequences of the purple allele BjMYB113a and the green allele BjMYB113b. On the other hand, the only sequence variation between the purple allele BjMYB113a and the green allele BjMYB113c is an insertion of 1,033-bp fragment in the 3'region of BjMYB113c. Transgenic assay and promoter activity studies showed that the polymorphism in the promoter region was responsible for the up-regulation of the purple allele BjMYB113a and high accumulation of anthocyanin in the purple cultivar. The up-regulation of BjMYB113a increased the expression of genes in the anthocyanin biosynthesis pathway including BjCHS, BjF3H, BjF3'H, BjDFR, BjANS and BjUGFT, and consequently led to high accumulation of anthocyanin. However, the up-regulation of BjMYB113 was compromised by the insertion of 1,033-bp in 3'region of the allele BjMYB113c. CONCLUSIONS: Our results contribute to a better understanding of the genetics and evolution of the BjMYB113 gene controlling purple leaves and provide useful information for further breeding programs of mustard.


Assuntos
Genes de Plantas/genética , Mutação com Perda de Função/genética , Mostardeira/genética , Folhas de Planta/anatomia & histologia , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Alelos , Antocianinas/metabolismo , Arabidopsis , Clonagem Molecular , Cor , Genes de Plantas/fisiologia , Mostardeira/anatomia & histologia , Mostardeira/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Fatores de Transcrição/fisiologia
7.
Molecules ; 26(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34070994

RESUMO

Ozone (O3) entry into plant leaves depends on atmospheric O3 concentration, exposure time and openness of stomata. O3 negatively impacts photosynthesis rate (A) and might induce the release of reactive volatile organic compounds (VOCs) that can quench O3, and thereby partly ameliorate O3 stress. Water stress reduces stomatal conductance (gs) and O3 uptake and can affect VOC release and O3 quenching by VOC, but the interactive effects of O3 exposure and water stress, as possibly mediated by VOC, are poorly understood. Well-watered (WW) and water-stressed (WS) Brassica nigra plants were exposed to 250 and 550 ppb O3 for 1 h, and O3 uptake rates, photosynthetic characteristics and VOC emissions were measured through 22 h recovery. The highest O3 uptake was observed in WW plants exposed to 550 ppb O3 with the greatest reduction and poorest recovery of gs and A, and elicitation of lipoxygenase (LOX) pathway volatiles 10 min-1.5 h after exposure indicating cellular damage. Ozone uptake was similar in 250 ppb WW and 550 ppb WS plants and, in both treatments, O3-dependent reduction in photosynthetic characteristics was moderate and fully reversible, and VOC emissions were little affected. Water stress alone did not affect the total amount and composition of VOC emissions. The results indicate that drought ameliorated O3 stress by reducing O3 uptake through stomatal closure and the two stresses operated in an antagonistic manner in B. nigra.


Assuntos
Mostardeira/metabolismo , Fotossíntese/fisiologia , Estresse Fisiológico/fisiologia , Transporte Biológico/fisiologia , Desidratação/metabolismo , Desidratação/fisiopatologia , Secas , Oxigênio/química , Oxigênio/metabolismo , Ozônio/metabolismo , Folhas de Planta/metabolismo , Estômatos de Plantas/metabolismo , Compostos Orgânicos Voláteis/química
8.
Theor Appl Genet ; 134(8): 2355-2365, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34173856

RESUMO

KEY MESSAGE: A candidate gene for male fertility restoration in Brassica juncea, BjRf, was isolated from a 23-kb interval on chromosome A05 using map-based cloning and BSA methods. The cytoplasmic male sterility/fertility restoration (CMS/Rf) system has been extensively used for heterosis in plants. It also provides valuable resources for studying mitochondrial-nuclear coevolution and interaction. The oxa CMS, which is a new CMS type reported in Brassica juncea (B. juncea), has been broadly used in the exploitation and application of heterosis in this species. However, the oxa CMS fertility restorer gene BjRf has not been reported. In this study, a stable restorer line was successfully constructed via continuous testcross and artificial selection. Besides, a new Rf gene was mapped in a 23-kb region on chromosome A05 in B. juncea with a genetic distance of 0.5 cM by the method incorporating bulk segregant analysis (BSA) and conventional map-based cloning. Finally, BjuA017917, a non-PPR Rf gene encoding a guanosine nucleotide diphosphate dissociation inhibitor (GDI), is proposed to be the candidate gene for fertility restoration of the oxa CMS line in B. juncea. Moreover, a functional marker, CRY3, was developed for marker-assisted selection for Brassica juncea breeding.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Mostardeira/genética , Melhoramento Vegetal/métodos , Infertilidade das Plantas , Proteínas de Plantas/genética , Mostardeira/crescimento & desenvolvimento , Mostardeira/metabolismo , Proteínas de Plantas/metabolismo
9.
Molecules ; 26(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809305

RESUMO

Plant growth-promoting rhizobacteria (PGPR) mediate heavy metal tolerance and improve phytoextraction potential in plants. The present research was conducted to find the potential of bacterial strains in improving the growth and phytoextraction abilities of Brassica nigra (L.) K. Koch. in chromium contaminated soil. In this study, a total of 15 bacterial strains were isolated from heavy metal polluted soil and were screened for their heavy metal tolerance and plant growth promotion potential. The most efficient strain was identified by 16S rRNA gene sequencing and was identified as Bacillus cereus. The isolate also showed the potential to solubilize phosphate and synthesize siderophore, phytohormones (indole acetic acid, cytokinin, and abscisic acid), and osmolyte (proline and sugar) in chromium (Cr+3) supplemented medium. The results of the present study showed that chromium stress has negative effects on seed germination and plant growth in B. nigra while inoculation of B. cereus improved plant growth and reduced chromium toxicity. The increase in seed germination percentage, shoot length, and root length was 28.07%, 35.86%, 19.11% while the fresh and dry biomass of the plant increased by 48.00% and 62.16%, respectively, as compared to the uninoculated/control plants. The photosynthetic pigments were also improved by bacterial inoculation as compared to untreated stress-exposed plants, i.e., increase in chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid was d 25.94%, 10.65%, 20.35%, and 44.30%, respectively. Bacterial inoculation also resulted in osmotic adjustment (proline 8.76% and sugar 28.71%) and maintained the membrane stability (51.39%) which was also indicated by reduced malondialdehyde content (59.53% decrease). The antioxidant enzyme activities were also improved to 35.90% (superoxide dismutase), 59.61% (peroxide), and 33.33% (catalase) in inoculated stress-exposed plants as compared to the control plants. B. cereus inoculation also improved the uptake, bioaccumulation, and translocation of Cr in the plant. Data showed that B. cereus also increased Cr content in the root (2.71-fold) and shoot (4.01-fold), its bioaccumulation (2.71-fold in root and 4.03-fold in the shoot) and translocation (40%) was also high in B. nigra. The data revealed that B. cereus is a multifarious PGPR that efficiently tolerates heavy metal ions (Cr+3) and it can be used to enhance the growth and phytoextraction potential of B. nigra in heavy metal contaminated soil.


Assuntos
Bacillus cereus/fisiologia , Cromo/farmacocinética , Mostardeira/metabolismo , Mostardeira/microbiologia , Poluentes do Solo/farmacocinética , Antioxidantes/metabolismo , Bacillus cereus/genética , Biodegradação Ambiental , Clorofila/metabolismo , Genes Bacterianos , Mostardeira/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Rhizobiaceae/fisiologia , Microbiologia do Solo , Estresse Fisiológico , Simbiose
10.
Plant Cell Environ ; 44(1): 234-246, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32978825

RESUMO

Spontaneous fertility reversion has been documented in cytoplasmic male sterile (CMS) plants of several species, influenced in frequency by nuclear genetic background. In this study, we found that MutS HOMOLOG1 (MSH1) mediates fertility reversion via substoichiometric shifting (SSS) of the CMS-associated mitochondrial Open Reading Frame 220 (ORF220), a process that may be regulated by pollination signalling in Brassica juncea. We show that plants adjust their growth and development in response to unsuccessful pollination. Measurable decrease in MSH1 transcript levels and evidence of ORF220 SSS under non-pollination conditions suggest that this nuclear-mitochondrial interplay influences fertility reversion in CMS plants in response to physiological signals. Suppression of MSH1 expression induced higher frequency SSS in CMS plants than occurs normally. Transcriptional analysis of floral buds under pollination and non-pollination conditions, and the response of MSH1 expression to different sugars, supports the hypothesis that carbon flux is involved in the pollination signalling of fertility reversion in CMS plants. Our findings suggest that facultative gynodioecy as a reproductive strategy may incorporate environmentally responsive genes like MSH1 as an "on-off" switch for sterility-fertility transition under ecological conditions of reproductive isolation.


Assuntos
Mostardeira/metabolismo , Proteína MutS de Ligação de DNA com Erro de Pareamento/metabolismo , Infertilidade das Plantas , Proteínas de Plantas/metabolismo , Frutose/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucose/metabolismo , Mostardeira/genética , Polinização , Sacarose/metabolismo
11.
Plant Mol Biol ; 105(1-2): 161-175, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32997301

RESUMO

KEY MESSAGE: Genome wide association studies allowed prediction of 17 candidate genes for association with nitrogen use efficiency. Novel information obtained may provide better understanding of genomic controls underlying germplasm variations for this trait in Indian mustard. Nitrogen use efficiency (NUE) of Indian mustard (Brassica juncea (L.) Czern & Coss.) is low and most breeding efforts to combine NUE with crop performance have not succeeded. Underlying genetics also remain unexplored. We tested 92 SNP-genotyped inbred lines for yield component traits, N uptake efficiency (NUPEFF), nitrogen utilization efficiency (NUTEFF), nitrogen harvest index (NHI) and NUE for two years at two nitrogen doses (No without added N and N100 added @100 kg/ha). Genotypes IC-2489-88, M-633, MCP-632, HUJM 1080, GR-325 and DJ-65 recorded high NUE at low N. These also showed improved crop performance under high N. One determinate mustard genotype DJ-113 DT-3 revealed maximum NUTEFF. Genome wide association studies (GWAS) facilitated recognition of 17 quantitative trait loci (QTLs). Environment specificity was high. B-genome chromosomes (B02, B03, B05, B07 and B08) harbored many useful loci. We also used regional association mapping (RAM) to supplement results from GWAS. Annotation of the genomic regions around peak SNPs helped to predict several gene candidates for root architecture, N uptake, assimilation and remobilization. CAT9 (At1g05940) was consistently envisaged for both NUE and NUPEFF. Major N transporter genes, NRT1.8 and NRT3.1 were predicted for explaining variation for NUTEFF and NUPEFF, respectively. Most significant amino acid transporter gene, AAP1 appeared associated with NUE under limited N conditions. All these candidates were predicted in the regions of high linkage disequilibrium. Sequence information of the predicted candidate genes will permit development of molecular markers to aid breeding for high NUE.


Assuntos
Mostardeira/genética , Mostardeira/metabolismo , Nitrogênio/metabolismo , Genes de Plantas , Estudo de Associação Genômica Ampla , Genótipo , Desequilíbrio de Ligação , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
12.
Chemosphere ; 262: 128384, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182105

RESUMO

Arsenic (As) polluted food chain has become a serious issue for the growth and development of humans, animals and plants. Nitric oxide (NO) or silicon (Si) may mitigate As toxicity. However, the combined application of NO and Si in mitigating As uptake and phytotoxicity in Brassica juncea is unknown. Hence, the collegial effect of sodium nitroprusside (SNP), a NO donor and Si application on B. juncea growth, gas exchange parameters, antioxidant system and As uptake was examined in a greenhouse experiment. Arsenic toxicity injured cell membrane as signposted by the elevated level of malondialdehyde (MDA) and hydrogen peroxide (H2O2), thus decreasing the growth of stressed plants. Moreover, As stress negatively affected gas exchange parameters and antioxidative system of plants. However, NO or/and Si alleviated As induced oxidative stress through increasing the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione S-transferase (GST), glutathione (GSH), along with thiol and proline synthesis. Furthermore, plants treated with co-application of NO and Si showed improved growth, gas attributes and decreased As uptake under As regimes. The current study highlights that NO and Si synergistically interact to mitigate detrimental effects of As stress through reducing As uptake. Our findings recommend combined NO and Si application in As spiked soils for improvement of plant growth and stress alleviation.


Assuntos
Arsênio/metabolismo , Mostardeira/fisiologia , Óxido Nítrico/química , Silício/química , Poluentes do Solo/metabolismo , Antioxidantes/metabolismo , Arsênio/toxicidade , Ascorbato Peroxidases/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Mostardeira/metabolismo , Doadores de Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Plântula/efeitos dos fármacos , Poluentes do Solo/toxicidade , Superóxido Dismutase/metabolismo
13.
Bull Environ Contam Toxicol ; 105(3): 411-421, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32725326

RESUMO

Phytoremediation is an ecologically and economically feasible technique to remove heavy metal from soil. The aim of the study was to examine cadmium (Cd) toxicity and phytoremediation aptitude of Brassica juncea. In the present study, plants survived when exposed to different levels of Cd (0, 25, 50 and 100 mg/kg soil) and accumulated a large amount of Cd in its root and shoot. Translocation factor (TF) of Cd from root to shoot was > 1 at both 45 and 60-day stage of growth suggesting that B. juncea is a hyperaccumulator and strong candidate for phytoextraction of Cd. Alongside, Cd impaired photolysis of water, PSII activity, nutrient uptake, photosynthesis and sugar accumulation in the plant. Cd-generated oxidative stress restricts the growth of B. juncea. The toxic effect of Cd was more pronounced at 45-day stage of growth signifying the drifting of plant towards acquirement of exclusion strategy.


Assuntos
Biodegradação Ambiental , Cádmio/metabolismo , Mostardeira/metabolismo , Poluentes do Solo/metabolismo , Cádmio/análise , Metabolismo dos Carboidratos , Gases , Metais Pesados/metabolismo , Mostardeira/efeitos dos fármacos , Mostardeira/crescimento & desenvolvimento , Oxirredução , Solo , Poluentes do Solo/análise
14.
IET Nanobiotechnol ; 14(5): 423-427, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32691746

RESUMO

Due to unique physiochemical properties, nanoparticles (NPs) have acquired substantial attention in the field of research. However, threats of ecotoxicity and phytotoxicity have limited their biological applications. In this study in vivo experiments were performed to determine the effect of CuO (12.5, 25 and 50 mg/kg) and ZnO (200, 400 and 600 mg/kg) NPs on growth, and antioxidant activities of Brassica nigra. The results showed that CuO NPs did not affect the seed germination while presence of ZnO NPs in the soil generated an inhibitory effect. Both CuO and ZnO NPs positively influenced the growth of stem and other physiological parameters i.e. stem height increased (23%) at 50 mg/kg CuO while root length decreased (up to 44%) with an increase in the concentration of NPs. Phytochemical screening of apical, middle and basal leaves showed elevated phenolic and flavonoid contents in the range of 15.3-59 µg Gallic Acid Equivalent (GAE)/mg Dry Weight (DW) and 10-35 µg Querceitin Equivalent (QE)/mg DW, respectively, in NPs-treated plants. Antioxidant activity was higher in CuO NPs-treated plants as compared to ZnO and control plants. Results conclude that CuO and ZnO NPs at low concentrations can be exploited as nanofertilisers in agriculture fields.


Assuntos
Antioxidantes/metabolismo , Cobre/toxicidade , Nanopartículas Metálicas/toxicidade , Mostardeira/efeitos dos fármacos , Óxido de Zinco/toxicidade , Flavonoides/análise , Flavonoides/metabolismo , Germinação/efeitos dos fármacos , Mostardeira/química , Mostardeira/metabolismo , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Solo/química
15.
Environ Microbiol ; 22(11): 4545-4556, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32656968

RESUMO

Agricultural production is dependent on inputs of nitrogen (N) whose cycle relies on soil and crop microbiomes. Crop diversification has increased productivity; however, its impact on the expression of microbial genes involved in N-cycling pathways remains unknown. Here, we assessed N-cycling gene expression patterns in the root and rhizosphere microbiomes of five oilseed crops as influenced by three 2-year crop rotations. The first phase consisted of fallow, lentil or wheat, and the second phase consisted of one of five oilseed crops. Expression of bacterial amoA, nirK and nirS genes showed that the microbiome of Ethiopian mustard had the lowest and that of camelina the highest potential for N loss. A preceding rotation phase of lentil significantly increased the expression of nifH gene by 23% compared with wheat and improved nxrA gene expression by 51% with chemical fallow in the following oilseed crops respectively. Lentil substantially increased biological N2 fixation and reduced denitrification in the following oilseed crops. Our results also revealed that most N-cycling gene transcripts are more abundant in the microbiomes associated with roots than with the rhizosphere. The outcome of our investigation brings a new level of understanding on how crop diversification and rotation sequences are related to N-cycling in annual cropping systems.


Assuntos
Camellia/metabolismo , Produtos Agrícolas/microbiologia , Lens (Planta)/metabolismo , Mostardeira/metabolismo , Ciclo do Nitrogênio/fisiologia , Triticum/metabolismo , Agricultura/métodos , Bactérias/genética , Camellia/microbiologia , Produção Agrícola/métodos , Lens (Planta)/microbiologia , Microbiota/fisiologia , Mostardeira/microbiologia , Nitrogênio/metabolismo , Ciclo do Nitrogênio/genética , Raízes de Plantas/microbiologia , Rizosfera , Solo , Microbiologia do Solo , Triticum/microbiologia
16.
PLoS One ; 15(6): e0234738, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544205

RESUMO

Tuber mustard, which is the raw material of Fuling pickle, is a crop with great economic value. However, during growth and development, tuber mustard is frequently attacked by the pathogen Plasmodiophora brassicae and frequently experiences salinity stress. Jasmonic acid (JA) is a hormone related to plant resistance to biotic and abiotic stress. Jasmonate ZIM domain proteins (JAZs) are crucial components of the JA signaling pathway and play important roles in plant responses to biotic and abiotic stress. To date, no information is available about the characteristics of the JAZ family genes in tuber mustard. Here, 38 BjJAZ genes were identified in the whole genome of tuber mustard. The BjJAZ genes are located on 17 of 18 chromosomes in the tuber mustard genome. The gene structures and protein motifs of the BjJAZ genes are conserved between tuber mustard and Arabidopsis. The results of qRT-PCR analysis showed that BjuA030800 was specifically expressed in root, and BjuA007483 was specifically expressed in leaf. In addition, 13 BjJAZ genes were transiently induced by P. brassicae at 12 h, and 7 BjJAZ genes were induced by salt stress from 12 to 24 h. These results provide valuable information for further studies on the role of BjJAZ genes in the regulation of plant growth and development and in the response to biotic and abiotic stress.


Assuntos
Genoma de Planta , Mostardeira/genética , Proteínas de Plantas/genética , Proteínas Repressoras/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Família Multigênica , Mostardeira/metabolismo , Oxilipinas/metabolismo , Filogenia , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Domínios Proteicos , RNA de Plantas/metabolismo , Proteínas Repressoras/classificação , Proteínas Repressoras/metabolismo , Estresse Fisiológico
17.
Environ Pollut ; 261: 114213, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32408418

RESUMO

Brassica juncea L. is an attractive species in PTMs contaminated soil remediation ascribing to its high tolerance under stress and great accumulation capacity of metals. To identify the potential Cd/Zn accumulators from numerous different Chinese mustard cultivars for practical phytoremediation is a promising strategy in China. In present work, a pot experiment involving elevated Cd/Zn concentrations was performed among 21 cultivars. Regarding physiological and biochemical indicators under Cd/Zn stress, principal component analysis and cluster analysis were used for cultivar tolerance evaluation and classification. Results showed that BJ (Bao Jie, var. involutus) cultivar was distinguished as a potential phytoremediation candidate comparing with other cultivars. Moreover, BJ accumulated the maximum Cd content of 63.85 and 77.29 mg kg-1 DW in shoots and roots, respectively, and the maximum Zn uptake by BJ were 6693 and 4777 mg kg-1 DW in shoots and roots, respectively. Accordingly, BJ had the highest Cd/Zn tolerance, remarkable accumulation and translocation capacity (accumulation factor (AF) > 1 for Cd and Zn; translocation factor (TF) > 0.8 for Cd and TF > 1 for Zn). In addition, the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities of the mustard increased initially under low Cd/Zn stress as compared to the control and then declined dramatically with the increasing metals exposure concentration. Therefore, the antioxidant enzymes may play a protective role against reactive oxygen species (ROS) under low Cd/Zn stress, whereas the defense system might be collapsed under relatively high Cd/Zn stress. Furthermore, the enhanced Cd/Zn exposure led to an increase in malondialdehyde (MDA) content in the mustard cultivars, indicating that Cd/Zn had induced more severe oxidative stress and higher degree of lipid peroxidation had occurred. The present investigation results indicated that BJ (Bao Jie, var. involutus), as a native cultivar, can be further applied in the field trials of phytoremediation practices in contaminated soil.


Assuntos
Cádmio/metabolismo , Mostardeira/metabolismo , Poluentes do Solo/metabolismo , Zinco/metabolismo , Antioxidantes , Biodegradação Ambiental , Cádmio/análise , China , Raízes de Plantas , Poluentes do Solo/análise , Zinco/análise
18.
Sci Rep ; 10(1): 8531, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444606

RESUMO

The present work describes the in vitro synthesis and characterization of Zinc oxide nanoparticles (ZnO NPs) using an enzyme alpha amylase, the synthesized nanoparticles were used to study their beneficial effect in the growth and development of Brassica juncea. Transmission Electron Microscope (TEM) image reveals the average size of ZnO NPs was 11 nm and X-ray powder diffraction (XRD) suggests nanoparticles were crystalline in nature. In-silico study confirmed lysine, glutamine and tyrosine present in alpha amylase enzyme, plays a crucial role in the reduction of Zinc acetate dihydrate to ZnO NPs. The biochemical parameters and oxidative enzymes of Brassica juncea were compared with ZnO NPs treated plants. The effect of ZnO NPs on the cellular expression of metal tolerant protein (BjMTP) and cation efflux transporter gene (BjCET2) was also studied. The results indicate that nanoparticles can be used as a replacement for traditional harmful chemical fertilizers.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Mostardeira/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Óxido de Zinco/química , Óxido de Zinco/metabolismo , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Mostardeira/efeitos dos fármacos , Mostardeira/metabolismo , Mostardeira/ultraestrutura , Oxirredução , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo
19.
Arch Insect Biochem Physiol ; 104(4): e21690, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32394499

RESUMO

The harlequin bug (HB), Murgantia histrionica, is a major pest of cabbage family plants throughout its range in the United States. RNA interference (RNAi) is a posttranscriptional gene silencing mechanism that is showing promise as a biopesticide due to the ability to target species-specific genes necessary for growth and/or survival with synthetic double-stranded RNA (dsRNA). In the present study, dsRNA stability assays revealed that nucleases present in the saliva of harlequin bugs did not rapidly degrade dsRNA. We tracked the movement and localization of radioactively labeled dsRNA in both mustard plant seedlings and harlequin bug nymphs that fed on treated host plants. Movement of 32 P-labeled-dsRNA from soil to plant and plant to insect was detected. The efficacy of RNAi in inducing mortality in harlequin bug adults and nymphs injected or fed with dsRNA targeting inhibitor of apoptosis (IAP), ATPase N2B (ATPase), serine/threonine-protein phosphatase PP1-ß catalytic subunit (PP1), signal recognition particle 54 kDa protein (SRP), and G protein-coupled receptor 161-like (GPCR) genes was evaluated. Injection of dsRNA targeting candidate genes into adults caused between 40% and 75% mortality and induced significant knockdown of target gene expression. Feeding dsRNA targeting the IAP gene to nymphs by plant-mediated and droplet feeding methods induced knockdown of the target gene and caused 40-55% mortality. These findings suggest that RNAi may be a viable approach for managing this pest.


Assuntos
Heterópteros/genética , Mostardeira/metabolismo , Interferência de RNA , Animais , Perfilação da Expressão Gênica , Heterópteros/crescimento & desenvolvimento , Heterópteros/metabolismo , Proteínas Inibidoras de Apoptose/genética , Controle de Insetos/métodos , Mostardeira/parasitologia , Ninfa/genética , Ninfa/metabolismo , Fenômenos Fisiológicos Vegetais , RNA de Cadeia Dupla , Ribonucleases , Saliva/enzimologia , Solo/química
20.
Molecules ; 25(5)2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182961

RESUMO

Plant-based foods are characterized by significant amounts of bioactive molecules with desirable health benefits beyond basic nutrition. The Brassicaceae (Cruciferae) family consists of 350 genera; among them, Brassica is the most important one, which includes some crops and species of great worldwide economic importance. In this work, the metabolite content of three different cultivars of Brassica juncea, namely ISCI Top, "Broad-leaf," and ISCI 99, was determined using comprehensive two-dimensional liquid chromatography coupled with a photodiode array and mass spectrometry detection. The analyses were carried out under reversed-phase conditions in both dimensions, using a combination of a 250-mm microbore cyano column and a 50-mm RP-Amide column in the first and second dimension (2D), respectively. A multi (three-step) segmented-in-fraction gradient for the 2D separation was advantageously investigated here for the first time, leading to the identification of 37 metabolites. In terms of resolving power, orthogonality values ranged from 62% to 69%, whereas the corrected peak capacity values were the highest for B. juncea ISCI Top (639), followed by B. juncea "Broad-leaf" (502). Regarding quantification, B. juncea cv. "Broad-leaf" presented the highest flavonoid content (1962.61 mg/kg) followed by B. juncea cv. ISCI Top (1002.03 mg/kg) and B. juncea cv. ISCI 99 (211.37 mg/kg).


Assuntos
Metaboloma , Mostardeira/química , Extratos Vegetais/química , Folhas de Planta/química , Cromatografia Líquida , Espectrometria de Massas , Mostardeira/classificação , Mostardeira/metabolismo
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