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1.
Nat Commun ; 12(1): 4327, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267202

RESUMO

Trivalent rare earth elements (REEs) are widely used in agriculture. Aerially applied REEs enter leaf epidermal cells by endocytosis and act systemically to improve the growth of the whole plant. The mechanistic basis of their systemic activity is unclear. Here, we show that treatment of Arabidopsis leaves with trivalent lanthanum [La(III)], a representative of REEs, triggers systemic endocytosis from leaves to roots. La(III)-induced systemic endocytosis requires AtrbohD-mediated reactive oxygen species production and jasmonic acid. Systemic endocytosis impacts the accumulation of mineral elements and the development of roots consistent with the growth promoting effects induced by aerially applied REEs. These findings provide insights into the mechanistic basis of REE activity in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Lantânio/farmacologia , NADPH Oxidases/metabolismo , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Ciclopentanos/metabolismo , Endocitose/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/genética , Minerais/metabolismo , NADPH Oxidases/genética , Oxilipinas/metabolismo , Células Vegetais/efeitos dos fármacos , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais
2.
Int J Mol Sci ; 22(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299166

RESUMO

As cell wall proteins, the hydroxyproline-rich glycoproteins (HRGPs) take part in plant growth and various developmental processes. To fulfil their functions, HRGPs, extensins (EXTs) in particular, undergo the hydroxylation of proline by the prolyl-4-hydroxylases. The activity of these enzymes can be inhibited with 3,4-dehydro-L-proline (3,4-DHP), which enables its application to reveal the functions of the HRGPs. Thus, to study the involvement of HRGPs in the development of root hairs and roots, we treated seedlings of Brachypodium distachyon with 250 µM, 500 µM, and 750 µM of 3,4-DHP. The histological observations showed that the root epidermis cells and the cortex cells beneath them ruptured. The immunostaining experiments using the JIM20 antibody, which recognizes the EXT epitopes, demonstrated the higher abundance of this epitope in the control compared to the treated samples. The transmission electron microscopy analyses revealed morphological and ultrastructural features that are typical for the vacuolar-type of cell death. Using the TUNEL test (terminal deoxynucleotidyl transferase dUTP nick end labelling), we showed an increase in the number of nuclei with damaged DNA in the roots that had been treated with 3,4-DHP compared to the control. Finally, an analysis of two metacaspases' gene activity revealed an increase in their expression in the treated roots. Altogether, our results show that inhibiting the prolyl-4-hydroxylases with 3,4-DHP results in a vacuolar-type of cell death in roots, thereby highlighting the important role of HRGPs in root hair development and root growth.


Assuntos
Apoptose , Brachypodium/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Prolina/farmacologia , Brachypodium/metabolismo , Hidroxiprolina/química , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Prolina/análogos & derivados
3.
BMC Plant Biol ; 21(1): 310, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210277

RESUMO

BACKGROUND: The ability of chickpea to obtain sufficient nitrogen via its symbiotic relationship with Mesorhizobium ciceri is of critical importance in supporting growth and grain production. A number of factors can affect this symbiotic relationship including abiotic conditions, plant genotype, and disruptions to host signalling/perception networks. In order to support improved nodule formation in chickpea, we investigated how plant genotype and soil nutrient availability affect chickpea nodule formation and nitrogen fixation. Further, using transcriptomic profiling, we sought to identify gene expression patterns that characterize highly nodulated genotypes. RESULTS: A study involving six chickpea varieties demonstrated large genotype by soil nitrogen interaction effects on nodulation and further identified agronomic traits of genotypes (such as shoot weight) associated with high nodulation. We broadened our scope to consider 29 varieties and breeding lines to examine the relationship between soilborne disease resistance and the number of nodules developed and real-time nitrogen fixation. Results of this larger study supported the earlier genotype specific findings, however, disease resistance did not explain differences in nodulation across genotypes. Transcriptional profiling of six chickpea genotypes indicates that genes associated with signalling, N transport and cellular localization, as opposed to genes associated with the classical nodulation pathway, are more likely to predict whether a given genotype will exhibit high levels of nodule formation. CONCLUSIONS: This research identified a number of key abiotic and genetic factors affecting chickpea nodule development and nitrogen fixation. These findings indicate that an improved understanding of genotype-specific factors affecting chickpea nodule induction and function are key research areas necessary to improving the benefits of rhizobial symbiosis in chickpea.


Assuntos
Cicer/genética , Resistência à Doença/efeitos dos fármacos , Nitrogênio/farmacologia , Nodulação/genética , Raízes de Plantas/fisiologia , Solo , Biomassa , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Genótipo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Nódulos Radiculares de Plantas/efeitos dos fármacos , Nódulos Radiculares de Plantas/metabolismo , Transcrição Genética/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
4.
Molecules ; 26(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070241

RESUMO

Lipoic acid (LA) and melatonin (MT) are pleiotropic molecules participating in plant stress resistance by modulating cellular biochemical changes, ion homeostasis, and antioxidant enzyme activities. However, the combined role of these two molecules in counteracting the detrimental impacts of salinity stress is still unknown. In the present study, we determined the effects of exogenous LA (0.5 µM), MT (1 µM) and their combination (LA + MT) on growth performance and biomass accumulation, photosynthetic pigments, enzymatic and non-enzymatic antioxidant activities, and ions homeostatic in canola (Brassica napus L.) seedlings under salinity stress (0, 100 mM) for 40 days. The results indicate that exogenous application of LA + MT improved the phenotypic growth (by 25 to 45%), root thickness (by 68%), number of later lateral roots (by 52%), root viability (by 44%), and root length (by 50%) under salinity stress. Moreover, total soluble protein, chlorophyll pigments, the concentration of superoxide dismutase (SOD), catalase peroxidase (CAT), and ascorbic peroxidase (ASA) increased with the presence of salt concentration into the growth media and then decreased with the addition of LA + MT to saline solution. Leaf protein contents and the degradation of photosynthetic pigments were lower when LA + MT treatments were added into NaCl media. The proline and phenol contents decreased in the exogenous application of LA + MT treatments more than individual LA or MT treatments under the salinity stress. The incorporation of LA or MT or a combination of LA + MT to saline solution decreased salinity-induced malondialdehyde and electrolyte leakage. In conclusion, the alteration of metabolic pathways, redox modulation, and ions homeostasis in plant tissues by the combined LA and MT application are helpful towards the adaptation of Brassica napus L. seedlings in a saline environment. The results of this study provide, for the first time, conclusive evidence about the protective role of exogenous LA + MT in canola seedlings under salinity stress.


Assuntos
Brassica napus/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Estresse Salino , Ácido Tióctico/farmacologia , Antioxidantes/metabolismo , Biomassa , Brassica napus/metabolismo , Produtos Agrícolas/metabolismo , Homeostase , Malondialdeído/metabolismo , Minerais/metabolismo , Fenóis/metabolismo , Fotossíntese/efeitos dos fármacos , Pigmentos Biológicos/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento
5.
Ecotoxicol Environ Saf ; 220: 112390, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34098428

RESUMO

Due to its immense capability to concentrate in rice grain and ultimately in food chain, cadmium (Cd) has become the cause of an elevated concern among agriculturists, scientists and the environmental activists. Symbiotic association of Piriformospora indica (P. indica) has been characterized as a potential aid in combating heavy metal stress in plants for sustainable crop production but our scant knowledge regarding ameliorative tendency of P. indica against Cd, specifically in rice, necessitates an in-depth investigation. This study aimed at elaborating the underlying mechanisms involved in P. indica-mediated tolerance against Cd stress in two rice genotypes, IR8 and ZX1H, varying in Cd accumulation pattern. Either colonized or un-inoculated with P. indica, seedlings of both genotypes were subjected to Cd stress. The results showed that P. indica colonization significantly supported plant biomass, photosynthetic attributes and chlorophyll contents in Cd stressed plants. P. indica colonization sustained chloroplast integrity and reduced Cd translocation (46% and 64%), significantly lowering malondialdehyde (MDA) content (11.3% and 50.4%) compared to uninoculated roots under Cd stress in IR8 and ZX1H, respectively. A genotypic difference was evident when a 2-fold enhancement in root peroxidase (POD) activity was recorded in P. indica colonized IR8 plants as compared to ZX1H. The root proteomic analysis was performed using isobaric tags for relative and absolute quantification (iTRAQ) and the results showed that P. indica alleviates Cd stress in rice via down-regulation of key glycolysis cycle enzymes in a bid to reduce energy consumption by the plants and possibly re-directing it to Cd defense response pathways; and up-regulation of glutamine synthetase, a key enzyme in the L-Arg-dependent pathway for nitric oxide (NO) production, which acts as a stress signaling molecule, thus conferring tolerance by reduction of NO-mediated modification of essential proteins in response to Cd stress. Conclusively, both the tested genotypes benefited from P. indica symbiosis at varying levels by an enhanced detoxification capacity and signaling efficiency in response to stress. Hence, a step forward towards the employment of an environmentally sound and self-renewing approach holding the hope for a healthy future.


Assuntos
Basidiomycota/fisiologia , Cádmio/toxicidade , Oryza/efeitos dos fármacos , Oryza/microbiologia , Raízes de Plantas/efeitos dos fármacos , Antioxidantes/metabolismo , Biomassa , Clorofila/metabolismo , Poluentes Ambientais/toxicidade , Malondialdeído/metabolismo , Oryza/metabolismo , Fotossíntese , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Proteômica , Plântula/metabolismo , Simbiose
6.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072168

RESUMO

This study aims to investigate whether the in vitro-cultured L. pumila var. alata has higher antioxidant activity than its wild plant. An 8-week-old L. pumila var. alata nodal segment and leaf explants were cultured onto Murashige and Skoog (MS) medium supplemented with various cytokinins (zeatin, kinetin, and 6-benzylaminopurine (BAP)) for shoot multiplication and auxins (2,4-dichlorophenoxyacetic acid (2,4-D) and picloram) for callus induction, respectively. The results showed that 2 mg/L zeatin produced the optimal results for shoot and leaf development, and 0.5 mg/L 2,4-D produced the highest callus induction results (60%). After this, 0.5 mg/L 2,4-D was combined with 0.25 mg/L cytokinins and supplemented to the MS medium. The optimal results for callus induction (100%) with yellowish to greenish and compact texture were obtained using 0.5 mg/L 2,4-D combined with 0.25 mg/L zeatin. Leaves obtained from in vitro plantlets and wild plants as well as callus were extracted and analyzed for their antioxidant activities (DPPH and FRAP methods) and polyphenolic properties (total flavonoid and total phenolic content). When compared with leaf extracts of in vitro plantlets and wild plants of L. pumila var. alata, the callus extract displayed significantly higher antioxidant activities and total phenolic and flavonoid content. Hence, callus culture potentially can be adapted for antioxidant and polyphenolic production to satisfy pharmaceutical and nutraceutical needs while conserving wild L. pumila var. alata.


Assuntos
Calo Ósseo/efeitos dos fármacos , Reguladores de Crescimento de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Polifenóis/química , Primulaceae/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/química , Antioxidantes/química , Compostos de Benzil/química , Compostos de Bifenilo/química , Meios de Cultura , Suplementos Nutricionais , Flavonoides/química , Técnicas In Vitro , Cinetina/química , Fenol/química , Picloram/química , Picratos/química , Folhas de Planta , Proteínas de Plantas , Raízes de Plantas/efeitos dos fármacos , Plantas/efeitos dos fármacos , Purinas/química , Zeatina/química
7.
Int J Mol Sci ; 22(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062942

RESUMO

A field experiment was established to study sweet potato growth, starch dynamic accumulation, key enzymes and gene transcription in the sucrose-to-starch conversion and their relationships under six K2O rates using Ningzishu 1 (sensitive to low-K) and Xushu 32 (tolerant to low-K). The results indicated that K application significantly improved the biomass accumulation of plant and storage root, although treatments at high levels of K, i.e., 300-375 kg K2O ha-1, significantly decreased plant biomass and storage root yield. Compared with the no-K treatment, K application enhanced the biomass accumulation of plant and storage root by 3-47% and 13-45%, respectively, through promoting the biomass accumulation rate. Additionally, K application also enhanced the photosynthetic capacity of sweet potato. In this study, low stomatal conductance and net photosynthetic rate (Pn) accompanied with decreased intercellular CO2 concentration were observed in the no-K treatment at 35 DAT, indicating that Pn was reduced mainly due to stomatal limitation; at 55 DAT, reduced Pn in the no-K treatment was caused by non-stomatal factors. Compared with the no-K treatment, the content of sucrose, amylose and amylopectin decreased by 9-34%, 9-23% and 6-19%, respectively, but starch accumulation increased by 11-21% under K supply. The activities of sucrose synthetase (SuSy), adenosine-diphosphate-glucose pyrophosphorylase (AGPase), starch synthase (SSS) and the transcription of Susy, AGP, SSS34 and SSS67 were enhanced by K application and had positive relationships with starch accumulation. Therefore, K application promoted starch accumulation and storage root yield through regulating the activities and genes transcription of SuSy, AGPase and SSS in the sucrose-to-starch conversion.


Assuntos
Glucose-1-Fosfato Adenililtransferase/genética , Glucosiltransferases/genética , Raízes de Plantas/crescimento & desenvolvimento , Potássio/farmacologia , Amilopectina/genética , Amilose/genética , Fertilização/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Amido/metabolismo , Sacarose/metabolismo
8.
Ecotoxicol Environ Saf ; 220: 112411, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111661

RESUMO

This study focused on the effects of eight medicinal plant extracts on Solanum nigrum L. potential to accumulate Cd and Pb from soil. These medicinal plants were common and relatively cheap. The eight 10% water extracts were made from the peel of Citrus reticulata Blanco (PCR), fruit of Phyllanthus emblica L. (FPE), root of Pueraria Lobata (Willd.) Ohwi (RPL), rhizome of Polygonatum sibiricum Red (RPS), root of Astragalus propinquus Schischkin (RAP), bud of Hemerocallis citrina Baroni (BHC), seed of Nelumbo nucifera Gaertn (SNN) and fruit of Prunus mume (Sieb.) Sieb.etZuce (FPM). The results showed that among all exposures, the treatment with FPE resulted in the significant increase (p < 0.05) of Cd and Pb concentration in shoots and roots of S. nigrum by 32.5% and 65.2% for Cd, and 38.7% and 39.6% for Pb. The biomasses of S. nigrum in all plant extract treatments were not significantly changed (p < 0.05) compared to the control (CK). The Cd and Pb extraction rates of S. nigrum in FPE treatment were increased respectively by 60.5% and 40.5% compared to CK. Though the treatment with EDTA significantly improved (p < 0.05) the concentration of Cd and Pb of S. nigrum, the Cd and Pb masses (ug plant-1) of S. nigrum did not show any significant difference compared to the CK due to the significant decrease in the shoot (20.4%) and root (22.0%) biomasses. The chelative role of FPE might be relation with its higher polyphenolic compounds. However, not sure if the contents of polyphenolic compounds was the only differences between FPE and other additives. Thus, some unknown organic matters might also play active role. This study provided valuable information on improving the phytoremediation potential of hyperaccumulator.


Assuntos
Metais Pesados/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Poluentes do Solo/metabolismo , Solanum nigrum/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Biomassa , Quelantes/química , Quelantes/farmacologia , Extratos Vegetais/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Solanum nigrum/metabolismo
9.
Ecotoxicol Environ Saf ; 220: 112410, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126303

RESUMO

Lead (Pb) toxicity is a growing serious environmental pollution that threatens human health and crop productivity. Poplar, as an important economic and ecological forest species, has the characteristics of fasting growth and accumulating heavy metals, which is a powerful model plant for phytoremediation. Here, a novel label-free quantitative proteomic platform of SWATH-MS was applied to detect proteome changes in poplar seedling roots following Pb treatment. In total 4388 unique proteins were identified and quantified, among which 542 proteins showed significant abundance changes upon Pb(II) exposure. Functional categorizations revealed that differentially expressed proteins (DEPs) primarily distributed in specialized biological processes. Particularly, lignin and flavonoid biosynthesis pathway were strongly activated upon Pb exposure, implicating their potential roles for Pb detoxification in poplar. Furthermore, hemicellulose and pectin related cell wall proteins exhibited increased abundances, where may function as a sequestration reservoir to reduce Pb toxicity in cytoplasm. Simultaneously, up-regulation of glutathione metabolism may serve as a protective role for Pb-induced oxidative damages in poplar. Further correlation investigation revealed an extra layer of post-transcriptional regulation during Pb response in poplar. Overall, our work represents multiply potential regulators in mediating Pb tolerance in poplar, providing molecular targets and strategies for phytoremediation.


Assuntos
Chumbo/toxicidade , Metais Pesados/toxicidade , Populus/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Biodegradação Ambiental , Vias Biossintéticas/efeitos dos fármacos , Chumbo/metabolismo , Metais Pesados/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Populus/metabolismo , Proteoma/metabolismo , Proteômica , Plântula/efeitos dos fármacos , Plântula/metabolismo
10.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068646

RESUMO

Nowadays, the use of biostimulants to reduce agrochemical input is a major trend in agriculture. In this work, we report on calcium phosphate particles (CaP) recovered from the circular economy, combined with natural humic substances (HSs), to produce a plant biostimulant. CaPs were obtained by the thermal treatment of Salmo salar bones and were subsequently functionalized with HSs by soaking in a HS water solution. The obtained materials were characterized, showing that the functionalization with HS did not sort any effect on the bulk physicochemical properties of CaP, with the exception of the surface charge that was found to get more negative. Finally, the effect of the materials on nutrient uptake and translocation in the early stages of development (up to 20 days) of two model species of interest for horticulture, Valerianella locusta and Diplotaxis tenuifolia, was assessed. Both species exhibited a similar tendency to accumulate Ca and P in hypogeal tissues, but showed different reactions to the treatments in terms of translocation to the leaves. CaP and CaP-HS treatments lead to an increase of P accumulation in the leaves of D. tenuifolia, while the treatment with HS was found to increase only the concentration of Ca in V. locusta leaves. A low biostimulating effect on both plants' growth was observed, and was mainly scribed to the low concentration of HS in the tested materials. In the end, the obtained material showed promising results in virtue of its potential to elicit phosphorous uptake and foliar translocation by plants.


Assuntos
Agricultura/economia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Substâncias Húmicas/análise , Plantas/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Peixes , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plântula/anatomia & histologia , Plântula/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Valerianella/química , Difração de Raios X
11.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068829

RESUMO

Cassia abbreviata is widely used in Sub-Saharan Africa for treating many diseases, including HIV-1 infection. We have recently described the chemical structures of 28 compounds isolated from an alcoholic crude extract of barks and roots of C. abbreviata, and showed that six bioactive compounds inhibit HIV-1 infection. In the present study, we demonstrate that the six compounds block HIV-1 entry into cells: oleanolic acid, palmitic acid, taxifolin, piceatannol, guibourtinidol-(4α→8)-epiafzelechin, and a novel compound named as cassiabrevone. We report, for the first time, that guibourtinidol-(4α→8)-epiafzelechin and cassiabrevone inhibit HIV-1 entry (IC50 of 42.47 µM and 30.96 µM, respectively), as well as that piceatannol interacts with cellular membranes. Piceatannol inhibits HIV-1 infection in a dual-chamber assay mimicking the female genital tract, as well as HSV infection, emphasizing its potential as a microbicide. Structure-activity relationships (SAR) showed that pharmacophoric groups of piceatannol are strictly required to inhibit HIV-1 entry. By a ligand-based in silico study, we speculated that piceatannol and norartocarpetin may have a very similar mechanism of action and efficacy because of the highly comparable pharmacophoric and 3D space, while guibourtinidol-(4α→8)-epiafzelechin and cassiabrevone may display a different mechanism. We finally show that cassiabrevone plays a major role of the crude extract of CA by blocking the binding activity of HIV-1 gp120 and CD4.


Assuntos
Cassia/química , Infecções por HIV/tratamento farmacológico , Extratos Vegetais/farmacologia , Internalização do Vírus/efeitos dos fármacos , Catequina/farmacologia , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Ácido Oleanólico/farmacologia , Ácido Palmítico/farmacologia , Extratos Vegetais/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/virologia , Quercetina/análogos & derivados , Quercetina/farmacologia , Estilbenos/farmacologia
12.
Int J Mol Sci ; 22(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066536

RESUMO

Plant food production is severely affected by fungi; to cope with this problem, farmers use synthetic fungicides. However, the need to reduce fungicide application has led to a search for alternatives, such as biostimulants. Rare-earth elements (REEs) are widely used as biostimulants, but their mode of action and their potential as an alternative to synthetic fungicides have not been fully studied. Here, the biostimulant effect of gadolinium (Gd) is explored using the plant-pathosystem Arabidopsis thaliana-Botrytis cinerea. We determine that Gd induces local, systemic, and long-lasting plant defense responses to B. cinerea, without affecting fungal development. The physiological changes induced by Gd have been related to its structural resemblance to calcium. However, our results show that the calcium-induced defense response is not sufficient to protect plants against B. cinerea, compared to Gd. Furthermore, a genome-wide transcriptomic analysis shows that Gd induces plant defenses and modifies early and late defense responses. However, the resistance to B. cinerea is dependent on JA/ET-induced responses. These data support the conclusion that Gd can be used as a biocontrol agent for B. cinerea. These results are a valuable tool to uncover the molecular mechanisms induced by REEs.


Assuntos
Arabidopsis/imunologia , Arabidopsis/microbiologia , Botrytis/fisiologia , Ciclopentanos/metabolismo , Etilenos/metabolismo , Gadolínio/farmacologia , Oxilipinas/metabolismo , Substâncias Protetoras/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
13.
BMC Plant Biol ; 21(1): 227, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020594

RESUMO

BACKGROUND: Root hypoxia has detrimental effects on physiological processes and growth in most plants. The effects of hypoxia can be partly alleviated by ethylene. However, the tolerance mechanisms contributing to the ethylene-mediated hypoxia tolerance in plants remain poorly understood. RESULTS: In this study, we examined the effects of root hypoxia and exogenous ethylene treatments on leaf gas exchange, root hydraulic conductance, and the expression levels of several aquaporins of the plasma membrane intrinsic protein group (PIP) in trembling aspen (Populus tremuloides) seedlings. Ethylene enhanced net photosynthetic rates, transpiration rates, and root hydraulic conductance in hypoxic plants. Of the two subgroups of PIPs (PIP1 and PIP2), the protein abundance of PIP2s and the transcript abundance of PIP2;4 and PIP2;5 were higher in ethylene-treated trembling aspen roots compared with non-treated roots under hypoxia. The increases in the expression levels of these aquaporins could potentially facilitate root water transport. The enhanced root water transport by ethylene was likely responsible for the increase in leaf gas exchange of the hypoxic plants. CONCLUSIONS: Exogenous ethylene enhanced root water transport and the expression levels of PIP2;4 and PIP2;5 in hypoxic roots of trembling aspen. The results suggest that ethylene facilitates the aquaporin-mediated water transport in plants exposed to root hypoxia.


Assuntos
Aquaporinas/genética , Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Populus/metabolismo , Água/metabolismo , Aquaporinas/metabolismo , Transporte Biológico , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Populus/efeitos dos fármacos , Populus/genética
14.
Ecotoxicol Environ Saf ; 219: 112312, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33989917

RESUMO

Copper (Cu) pollution is common in the soil. Due to the widespread application of TiO2 NPs, there is a high propensity for the co-occurrence of TiO2 nanoparticles (NPs) and Cu in agricultural soils. It is therefore imperative to evaluate the joint effects of TiO2 NPs and Cu on crops. In this study, the mutual effects of TiO2 NPs and Cu on their toxicity and accumulation in soybean seedlings and on their fates in a hydroponic system were determined. When Cu was at levels of 1 and 2 mg/L, the co-occurring TiO2 NPs at a non-toxic concentration (10 mg/L) significantly enhanced the toxicity and accumulation of Cu and Ti in soybeans, and inhibited the translocation of Cu from soybean roots to shoots. However, when the Cu concentration for co-exposure was ≥ 5 mg/L, such mutual effects disappeared. The amount of Cu ions adsorbed onto TiO2 NPs after 48 h of co-exposure gradually increased from 31 to 118 mg/g when the Cu concentration was increased from 1 to 20 mg/L. The aggregation and sedimentation of TiO2 NPs were significantly increased after 48 h of co-exposure with the Cu at a concentration higher than 5 mg/L, as compared to the single TiO2 NPs exposure. The increasing aggregation and sedimentation might reduce the bioavailability of TiO2 NPs associated with the adsorbed Cu to soybeans, and consequently alleviate or even neutralize the enhanced toxicity and accumulation of Cu in soybeans exerted by the co-existing TiO2 NPs. Our results thus suggest that consideration of the impact of TiO2 NPs on the phytotoxicity of heavy metals, and specifically Cu, needs to be interpreted with care, and highlight the importance of integrating the interaction and fates of TiO2 NPs and metals into their risk assessment.


Assuntos
Cobre/metabolismo , Nanopartículas/toxicidade , Titânio/toxicidade , Adsorção , Disponibilidade Biológica , Cobre/toxicidade , Produtos Agrícolas , Fabaceae , Hidroponia , Metais Pesados/farmacologia , Raízes de Plantas/efeitos dos fármacos , Plântula/efeitos dos fármacos , Solo , Soja
15.
Methods Mol Biol ; 2290: 271-284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34009596

RESUMO

Various steps of micropropagation include selection of suitable explant, establishment of adventitious shoot induction cultures, proliferation, rooting, and acclimatization of the resulting plantlets. A systematic protocol is provided for the micropropagation and Agrobacterium tumefaciens-mediated genetic transformation of a fast growing, multipurpose tree, Paulownia elongata. Our studies show that optimum shoot induction is on half leaf with petiole explant on MS medium supplemented with 25 µM thidiazuron and 10 µM indole-3 acetic acid. Micropropagation protocols provided here are applicable to explants collected from the primed in vitro raised seedlings on MS medium containing 2.5 µM 6-benzylaminopurine (BAP) or actively growing shoots collected from greenhouse or field growing plants. We also discuss a possible role of "Python" script guided protocol optimization for higher and consistent multiplication of shoots that can be very helpful for scaled up production in commercial settings. To facilitate future plant improvement and gene editing possibilities, an A. tumefaciens based genetic transformation protocol and molecular identification of transgenic plants using Polymerase Chain Reaction (PCR) and Reverse Transcriptase-PCR (RT-PCR) techniques have also been optimized.


Assuntos
Lamiales/genética , Melhoramento Vegetal/métodos , Agrobacterium tumefaciens/efeitos dos fármacos , Meios de Cultura , Ácidos Indolacéticos/farmacologia , Lamiales/crescimento & desenvolvimento , Compostos de Fenilureia/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Plântula/efeitos dos fármacos , Tiadiazóis/farmacologia , Técnicas de Cultura de Tecidos/métodos , Transformação Genética/genética , Transformação Genética/fisiologia , Árvores/genética
16.
Genes (Basel) ; 12(3)2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803672

RESUMO

Iris lactea var. chinensis (I. lactea var. chinensis) is a perennial herb halophyte with salt and drought tolerance. In this study, full-length transcripts of I. lactea var. chinensis were sequenced using the PacBio RSII sequencing platform. Moreover, the transcriptome was investigated under NaCl or polyethylene glycol (PEG) stress. Approximately 30.89 G subreads were generated and 31,195 unigenes were obtained by clustering the same isoforms by the PacBio RSII platform. A total of 15,466 differentially expressed genes (DEGs) were obtained under the two stresses using the Illumina platform. Among them, 9266 and 8390 DEGs were obtained under high concentrations of NaCl and PEG, respectively. In total, 3897 DEGs with the same expression pattern under the two stresses were obtained. The transcriptome expression profiles of I. lactea var. chinensis under NaCl or PEG stress obtained in this study may provide a resource for the same and different response mechanisms against different types of abiotic stress. Furthermore, the stress-related genes found in this study can provide data for future molecular breeding.


Assuntos
Perfilação da Expressão Gênica/métodos , Iris (Planta)/crescimento & desenvolvimento , Proteínas de Plantas/genética , Polietilenoglicóis/efeitos adversos , Cloreto de Sódio/efeitos adversos , Embaralhamento de DNA , Secas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Iris (Planta)/efeitos dos fármacos , Iris (Planta)/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Estresse Salino , Sequenciamento Completo do Exoma
17.
Environ Geochem Health ; 43(6): 2317-2330, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33866466

RESUMO

Toxic metal phytoextraction potential of some higher plants, the white mustard (Sinapis alba L.), perennial rye grass (Lolium perenne L.) and also two cultivated plants, as green pea (Pisum sativum L. var. Rajnai törpe), radish (Raphanus sativus L. var. Szentesi óriás vaj), was studied in a field experiment, along the river Danube in close vicinity of an industrial town, Dunaújváros, Hungary. Soil/sediment and the various plant organs (leaves, stems and roots) were assessed for the contamination with some potentially toxic elements (PTE), such as the cadmium (Cd), nickel (Ni), copper (Cu), and zinc (Zn). It was found that Cd and Ni concentration was below, while the Cu and Zn elements were above the Hungarian permissible limits in each of the studied soil/sediment samples. Bioconcentration factor (BAF) was less than 1 in the shoot biomass of test plant samples and followed the order of Cu > Zn > Cd and Ni. Phytoremediation potential of selected test plants was found to be rather limited. The translocation factor (TF) was more than 1 for Cu and Zn elements, at each test plants. Cadmium was translocated into the leaves in case of the radish, only. Considering of the potential human daily intake of metals (DIM), it was less than 1 both for the adults and for the children. Health risk index (HRI) values of children, however, were higher than 1 for the Cd in case of radish, and for Zn and Cu in case of the pea. Results suggest that consumption of these plants grown in gardens of contaminated sediments can result in some risks for citizens in the industrial town of Dunaújváros. Further studies are required to identify appropriate plants with greater toxic metal phytoextraction potential.


Assuntos
Biodegradação Ambiental , Metais Pesados/isolamento & purificação , Ervilhas , Raphanus , Poluentes do Solo/isolamento & purificação , Biomassa , Exposição Dietética/efeitos adversos , Contaminação de Alimentos , Sedimentos Geológicos , Hungria , Lolium/química , Lolium/efeitos dos fármacos , Metais Pesados/análise , Metais Pesados/toxicidade , Ervilhas/química , Ervilhas/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/química , Brotos de Planta/efeitos dos fármacos , Raphanus/química , Raphanus/efeitos dos fármacos , Rios , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/análise
18.
Mutat Res ; 865: 503338, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33865544

RESUMO

Quantum Dots (QDs), are considered as promising tools for biomedical applications. They have potential applications in agricultural industries, novel pesticide formulations, use in bio-labels and devices to aid genetic manipulation and post-harvest management. Since interactions with higher plants are of important environmental and ecological concern we investigated the cytotoxicity and genotoxicity of CdSe QDs in a model plant (Allium cepa) and established relationships between QDs genotoxic activity and oxidative stress. Allium cepa bulbs with intact roots were exposed to three concentrations of CdSe QDs (12.5, 25 and 50 nM). Cell viability and mitotic frequencies was measured for cytotoxicity, and to assess the genotoxicity DNA lesions, chromosome aberrations and micronuclei were evaluated. We report that QDs exerted significant genotoxic effects, associated with oxidative stress. This could be correlated with the retention of Cd in Allium roots as a dose-dependent increase with the highest uptake at 50 nM of CdSe QD. Oxidative stress induced by CdSe QD treatment activated both, antioxidant (SOD, CAT) scavengers and antioxidant (GPOD, GSH) enzymes. Concentrations as low as 25 nM CdSe QDs were cytotoxic and 50 nM CdSe QDs was found to be genotoxic to the plant. These findings enable to determine the concentrations to be used when practical applications using nanodevices of this type on plants are being considered.


Assuntos
Compostos de Cádmio/toxicidade , Cebolas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pontos Quânticos/toxicidade , Compostos de Selênio/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ensaio Cometa , Dano ao DNA , Peroxidação de Lipídeos/efeitos dos fármacos , Testes para Micronúcleos , Testes de Mutagenicidade , Cebolas/genética , Cebolas/crescimento & desenvolvimento , Cebolas/metabolismo , Estresse Oxidativo/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
19.
Molecules ; 26(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806398

RESUMO

Bruguiera gymnorhiza (L.) Lam is a mangrove plant that spread in many parts of the world. Though mangrove plant polyphenols have been reported to exhibit many biological activities, little is known about mangrove plant tannins. To explore the application value of tannins from B. gymnorhiza, analyses on the structure and biological activity of condensed tannins (CTs) from Bruguiera gymnorhiza (L.) Lam were carried out. The results from 13C nuclear magnetic resonance (13C-NMR) and reversed-phase, high-performance liquid chromatography (RP-HPLC) showed that the CTs were dominated by procyanidins, with a small quantity of prodelphinidins and propelargonidins; and that the monomeric constituents of B. gymnorhiza tannins were catechin/epicatechin, gallocatechin/epigallocatechin and afzelechin/epiafzelechin. The CTs were reversible and mixed competitive inhibitors of tyrosinase and the 50% inhibiting concentration (IC50) was estimated to be 123.90 ± 0.140 µg/mL. The antioxidant activities of CTs from B. gymnorhiza leaves were evaluated, the IC50 for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid diammonium salt) (ABTS) scavenging activities were 88.81 ± 0.135 and 105.03 ± 0.130 µg/mL, respectively, and the ferric ion reducing antioxidant power (FRAP) value was 1052.27 ± 4.17 mgAAE/g. In addition, the results from fresh-keeping assays on fresh-cut lotus root reveal that CTs from B. gymnorhiza had excellent effects on inhibiting the activities of polyphenol oxidase (PPO) and peroxidase (POD), protecting fresh-cut lotus root from the oxidation of total phenolics and malondialdehyde (MDA) content and slowing the increase in total phenol content (TPC) at 4 °C during the whole storage period. Therefore, CTs showed good effects against the browning of fresh-cut lotus root. Together, these results suggested that B. gymnorhiza CTs are promising antibrowning agents for fresh-cut fruits.


Assuntos
Antioxidantes/farmacologia , Lotus/efeitos dos fármacos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Raízes de Plantas/efeitos dos fármacos , Rhizophoraceae/química , Taninos/farmacologia , Agaricales/enzimologia , Oxirredução , Proantocianidinas/análise , Taninos/isolamento & purificação
20.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800748

RESUMO

The plant hormone indole-3-acetic acid (IAA) is one of the main signals playing a role in the communication between host and endophytes. Endophytes can synthesize IAA de novo to influence the IAA homeostasis in plants. Although much is known about IAA biosynthesis in microorganisms, there is still less known about the pathway by which IAA is synthesized in fungal endophytes. The aim of this study is to examine a possible IAA biosynthesis pathway in Cyanodermella asteris. In vitro cultures of C. asteris were incubated with the IAA precursors tryptophan (Trp) and indole, as well as possible intermediates, and they were additionally treated with IAA biosynthesis inhibitors (2-mercaptobenzimidazole and yucasin DF) to elucidate possible IAA biosynthesis pathways. It was shown that (a) C. asteris synthesized IAA without adding precursors; (b) indole-3-acetonitrile (IAN), indole-3-acetamide (IAM), and indole-3-acetaldehyde (IAD) increased IAA biosynthesis; and (c) C. asteris synthesized IAA also by a Trp-independent pathway. Together with the genome information of C. asteris, the possible IAA biosynthesis pathways found can improve the understanding of IAA biosynthesis in fungal endophytes. The uptake of fungal IAA into Arabidopsis thaliana is necessary for the induction of lateral roots and other fungus-related growth phenotypes, since the application of the influx inhibitor 2-naphthoxyacetic acid (NOA) but not the efflux inhibitor N-1-naphtylphthalamic acid (NPA) were altering these parameters. In addition, the root phenotype of the mutation in an influx carrier, aux1, was partially rescued by C. asteris.


Assuntos
Arabidopsis/microbiologia , Ascomicetos/metabolismo , Endófitos/metabolismo , Adaptação ao Hospedeiro , Ácidos Indolacéticos/metabolismo , Indóis/farmacologia , Raízes de Plantas/microbiologia , Triptofano/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Benzimidazóis/farmacologia , Meios de Cultivo Condicionados , Genoma Fúngico , Glicolatos/farmacologia , Especificidade de Hospedeiro , Ácidos Indolacéticos/farmacologia , Indóis/metabolismo , Redes e Vias Metabólicas/genética , Ftalimidas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Triazóis/farmacologia , Triptofano/metabolismo
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