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2.
Bioresour Technol ; 367: 128270, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36347483

RESUMO

In this study, a novel method of coupling phytohormones with saline wastewater was proposed to drive efficient microalgal lipid production. All the six phytohormones effectively promoted microalgae growth in saline wastewater, and further increased the microalgal lipid content based on salt stress, so as to achieve a large increase in microalgal lipid productivity. Among the phytohormones used, abscisic acid had the most significant promoting effect. Under the synergistic effect of 20 g/L salt and 20 mg/L abscisic acid, the microalgal lipid productivity reached 3.7 times that of the control. Transcriptome analysis showed that differentially expressed genes (DEGs) of microalgae in saline wastewater were mainly up-regulated under the effects of phytohormones except brassinolide. Common DEGs analysis showed that phytohormones all regulated the expression of genes related to DNA repair and substance synthesis. In conclusion, synergistic effect of salt stress and phytohormones can greatly improve the microalgal lipid production efficiency.


Assuntos
Microalgas , Microalgas/metabolismo , Reguladores de Crescimento de Plantas , Águas Residuárias , Ácido Abscísico/metabolismo , Lipídeos , Estresse Salino , Biomassa
3.
Microbiol Res ; 266: 127225, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36240664

RESUMO

Salt stress poses a global challenge for agriculture, crop growth, and food production. In this study, a strain of rhizobacteria with both plant growth-promoting (PGP) traits and salt tolerance was isolated. The strain was identified as Bacillus pumilus via 16 S rDNA sequencing and was named B. pumilus JIZ13. This strain had the potential to solubilize phosphates and produce 1-aminocyclopropane-1-carboxylic acid deaminase, siderophores, and indole-3-acetic acid. After 35 days of salt stress exposure, the root length, plant height, dry weight, fresh weight, and relative water content of rice plants inoculated with strain JIZ13 were significantly higher than those without inoculation. Interestingly, the PGP properties of strain JIZ13 were significantly improved by the exogenous addition of gamma-aminobutyric acid (GABA). Moreover, GABA also enhanced the growth and development of rice plants under salt stress by providing substrates for the tricarboxylic acid cycle. Furthermore, the synergistic roles of GABA and strain JIZ13 in mitigating the damage caused by salt stress in rice plants was investigated. The results showed that the co-application of GABA and JIZ13 significantly increased photosynthetic efficiency, chlorophyll accumulation, antioxidant levels, levels of osmotic adjustment substances, and biomass of rice under salinity stress. In addition, the activities of urease, protease, invertase, and catalase enzymes in soil significantly improved under the combination of strain JIZ13 and GABA and increased by 39.65%, 36.88%, 70.21%, and 65.23%, respectively, compared to those without rhizobacterial and GABA additions. The enhancement of these four soil enzyme activities might thus improve soil quality and increase root elongation and biomass in rice plants. The results of this study provide the first evidence that PGP-rhizobacterial strain JIZ13 along with GABA can attenuate the negative effects of salt stress in rice plants.


Assuntos
Bacillus , Oryza , Oryza/microbiologia , Solo/química , Bacillus/metabolismo , Antioxidantes/metabolismo , Raízes de Plantas/microbiologia , Estresse Salino , Fotossíntese , Ácido gama-Aminobutírico
4.
BMC Plant Biol ; 22(1): 540, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414951

RESUMO

BACKGROUND: Around the globe, salinity is one of the serious environmental stresses which negatively affect rapid seed germination, uniform seedling establishment and plant developments restricting sustainable agricultural productivity. In recent years, the concepts of sustainable agriculture and cleaner production strategy have emphasized the introduction of greener agrochemicals using biocompatible and natural sources to maximize crop yield with minimum ecotoxicological effects. Over the last decade, the emergence of nanotechnology as a forefront of interdisciplinary science has introduced nanomaterials as fast-acting plant growth-promoting agents. RESULTS: Herein, we report the preparation of nanocomposite using chitosan and green tea (CS-GTE NC) as an ecofriendly nanopriming agent to elicit salt stress tolerance through priming imprints. The CS-GTE NC-primed (0.02, 0.04 and 0.06%), hydroprimed and non-primed (control) wheat seeds were germinated under normal and salt stress (150 mM NaCl) conditions. The seedlings developed from aforesaid seeds were used for physiological, biochemical and germination studies. The priming treatments increased protein contents (10-12%), photosynthetic pigments (Chl a (4-6%), Chl b (34-36%), Total Chl (7-14%) and upregulated the machinery of antioxidants (CAT (26-42%), POD (22-43%)) in wheat seedlings under stress conditions. It also reduced MDA contents (65-75%) and regulated ROS production resulting in improved membrane stability. The priming-mediated alterations in biochemical attributes resulted in improved final germination (20-22%), vigor (4-11%) and germination index (6-13%) under both conditions. It reduced mean germination time significantly, establishing the stress-insulating role of the nanocomposite. The improvement of germination parameters validated the stimulation of priming memory in composite-treated seeds. CONCLUSION: Pre-treatment of seeds with nanocomposite enables them to counter salinity at the seedling development stage by means of priming memory warranting sustainable plant growth and high crop productivity.


Assuntos
Plântula , Triticum , Plântula/metabolismo , Germinação , Sementes , Estresse Salino
5.
Ecotoxicol Environ Saf ; 247: 114264, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334340

RESUMO

Salt stress severely affects the growth and productivity of Glycyrrhiza uralensis. Our previous research found that the endophyte Bacillus cereus G2 alleviated the osmotic and oxidative stress in G. uralensis exposed to salinity. However, the mechanism is still unclear. Here, a pot experiment was conducted to analyse the change in parameters related to osmotic adjustment and antioxidant metabolism by G2 in salt-stressed G. uralensis at the physio-biochemistry and transcriptome levels. The results showed that G2 significantly increased proline content by 48 %, glycine betaine content by 75 % due to activated expression of BADH1, and soluble sugar content by 77 % due to upregulated expression of α-glucosidase and SS, which might help to decrease the cell osmotic potential, enable the cell to absorb water, and stabilize the cell's protein and membrane structure, thereby alleviating osmotic stress. Regarding antioxidant metabolism, G2 significantly decreased malondialdehyde (MDA) content by 27 %, which might be ascribed to the increase in superoxide dismutase (SOD) activity that facilitated the decrease in the superoxide radical (O2‾) production rate; it also increased the activities of catalase (CAT), ascorbate peroxidase (APX) and glutathione peroxidase (GPX), which helped stabilize the normal level of hydrogen peroxide (H2O2). G2 also increased glutathione (GSH) content by 65 % due to increased glutathione reductase (GR) activity and GSH/GSSG ratio, but G2 decreased oxidized glutathione (GSSG) content by 13 % due to decreased activity of dehydroascorbate reductase (DHAR), which could provide sufficient substrates for the ascorbate-glutathione (AsA-GSH) cycle to eliminate excess H2O2 that was not cleared in a timely manner by the antioxidant enzyme system. Taken together, G2 alleviated osmotic stress by increasing proline, soluble sugar, and glycine betaine contents and alleviated oxidative stress by the synergistic effect of antioxidant enzymes and the AsA-GSH cycle. Therefore, the results may be useful for explaining the mechanism by which endophyte inoculation regulates the salt tolerance of crops.


Assuntos
Glycyrrhiza uralensis , Plântula , Bacillus cereus , Transcriptoma , Antioxidantes , Dissulfeto de Glutationa , Peróxido de Hidrogênio , Betaína/farmacologia , Estresse Salino , Estresse Oxidativo , Glutationa , Açúcares , Prolina
6.
Plant Physiol Biochem ; 193: 139-152, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36356545

RESUMO

High salinity and drought stresses often cause plants to produce ROS, including hydrogen peroxide (H2O2) and superoxide (O2-), which interfere with plant growth and affect crop yield. The transcription factors of the MYB family are involved in responses to biotic and abiotic stresses. Here, we isolated the R2R3-MYB transcription factor gene SlMYB50 and found that silencing of SlMYB50 increased resistance to PEG 6000, mannitol and salt. In addition, the resistance of transgenic tomatoes increased under high salt and drought stress. After stress treatment, the relative water content, chlorophyll content (critical for carbon fixation) and root vitality of the SlMYB50-RNAi lines were higher than those of the wild-type (WT). The opposite was true the water loss rate, relative conductivity, and MDA (as a sign of cell wall disruption). Under drought stress conditions, SlMYB50-silenced lines exhibited less H2O2 and less O2- accumulation, as well as higher CAT enzyme activity, than were exhibited by the WT. Notably, after stress treatment, the expression levels of chlorophyll-synthesis-related, flavonoid-synthesis-related, carotenoid-related, antioxidant-enzyme-related and ABA-biosynthesis-related genes were all upregulated in SlMYB50-silenced lines compared to those of WT. A dual-luciferase reporter system was used to verify that SlMYB50 could bind to the CHS1 promoter. In summary, this study identified essential roles for SlMYB50 in regulating drought and salt tolerance.


Assuntos
Secas , Lycopersicon esculentum , Lycopersicon esculentum/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino/genética , Estresse Fisiológico/genética , Clorofila , Água/metabolismo
7.
Int J Mol Sci ; 23(21)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36361560

RESUMO

Heat shock transcription factors (HSF) are divided into classes A, B and C. Class A transcription factors are generally recognized as transcriptional activators, while functional characterization of class B and C heat shock transcription factors have not been fully developed in most plant species. We isolated and characterized a novel HSF transcription factor gene, TrHSFB2a (a class B HSF) gene, from the drought stress-sensitive forage crop species, white clover (Trifolium repens). TrHSFB2a was highly homologous to MtHSFB2b, CarHSFB2a, AtHSFB2b and AtHSFB2a. The expression of TrHSFB2a was strongly induced by drought (PEG6000 15% w/v), high temperature (35 °C) and salt stresses (200 mM L-1 NaCl) in white clover, while subcellular localization analysis showed that it is a nuclear protein. Overexpression of the white clover gene TrHSFB2a in Arabidopsis significantly reduced fresh and dry weight, relative water contents (RWC), maximum photosynthesis efficiency (Fv/Fm) and performance index on the absorption basis (PIABS), while it promoted leaf senescence, relative electrical conductivity (REC) and the contents of malondialdehyde (MDA) compared to a wild type under drought, heat and salt stress conditions of Arabidopsis plants. The silencing of its native homolog (AtHSFB2a) by RNA interference in Arabidopsis thaliana showed opposite trends by significantly increasing fresh and dry weights, RWC, maximum photosynthesis efficiency (Fv/Fm) and performance index on the absorption basis (PIABS) and reducing REC and MDA contents under drought, heat and salt stress conditions compared to wild type Arabidopsis plants. These phenotypic and physiological indicators suggested that the TrHSFB2a of white clover functions as a negative regulator of heat, salt and drought tolerance. The bioinformatics analysis showed that TrHSFB2a contained the core B3 repression domain (BRD) that has been reported as a repressor activator domain in other plant species that might repress the activation of the heat shock-inducible genes required in the stress tolerance process in plants. The present study explores one of the potential causes of drought and heat sensitivity in white clover that can be overcome to some extent by silencing the TrHSFB2a gene in white clover.


Assuntos
Arabidopsis , Trifolium , Secas , Arabidopsis/metabolismo , Trifolium/genética , Trifolium/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Estresse Salino , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Medicago/metabolismo
8.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362058

RESUMO

Cultivated soybean (Glycine max (L.)), the world's most important legume crop, has high-to-moderate salt sensitivity. Being the frontier for sensing and controlling solute transport, membrane proteins could be involved in cell signaling, osmoregulation, and stress-sensing mechanisms, but their roles in abiotic stresses are still largely unknown. By analyzing salt-induced membrane proteomic changes in the roots and leaves of salt-sensitive soybean cultivar (C08) seedlings germinated under NaCl, we detected 972 membrane proteins, with those present in both leaves and roots annotated as receptor kinases, calcium-sensing proteins, abscisic acid receptors, cation and anion channel proteins, proton pumps, amide and peptide transporters, and vesicle transport-related proteins etc. Endocytosis, linoleic acid metabolism, and fatty acid biosynthesis pathway-related proteins were enriched in roots whereas phagosome, spliceosome and soluble NSF attachment protein receptor (SNARE) interaction-related proteins were enriched in leaves. Using label-free quantitation, 129 differentially expressed membrane proteins were found in both tissues upon NaCl treatment. Additionally, the 140 NaCl-induced proteins identified in roots and 57 in leaves are vesicle-, mitochondrial-, and chloroplast-associated membrane proteins and those with functions related to ion transport, protein transport, ATP hydrolysis, protein folding, and receptor kinases, etc. Our proteomic results were verified against corresponding gene expression patterns from published C08 RNA-seq data, demonstrating the importance of solute transport and sensing in salt stress responses.


Assuntos
Proteômica , Soja , Soja/genética , Proteômica/métodos , Proteínas de Membrana/metabolismo , Cloreto de Sódio/farmacologia , Cloreto de Sódio/metabolismo , Raízes de Plantas/metabolismo , Estresse Salino , Folhas de Planta/metabolismo , Plântula/genética , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
BMC Plant Biol ; 22(1): 528, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376811

RESUMO

BACKGROUND: Soil salinization and alkalization are widespread environmental problems that limit grapevine (Vitis vinifera L.) growth and yield. However, little is known about the response of grapevine to alkali stress. This study investigated the differences in physiological characteristics, chloroplast structure, transcriptome, and metabolome in grapevine plants under salt stress and alkali stress. RESULTS: We found that grapevine plants under salt stress and alkali stress showed leaf chlorosis, a decline in photosynthetic capacity, a decrease in chlorophyll content and Rubisco activity, an imbalance of Na+ and K+, and damaged chloroplast ultrastructure. Fv/Fm decreased under salt stress and alkali stress. NPQ increased under salt stress whereas decreased under alkali stress. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed the differentially expressed genes (DEGs) induced by salt stress and alkali stress were involved in different biological processes and have varied molecular functions. The expression of stress genes involved in the ABA and MAPK signaling pathways was markedly altered by salt stress and alkali stress. The genes encoding ion transporter (AKT1, HKT1, NHX1, NHX2, TPC1A, TPC1B) were up-regulated under salt stress and alkali stress. Down-regulation in the expression of numerous genes in the 'Porphyrin and chlorophyll metabolism', 'Photosynthesis-antenna proteins', and 'Photosynthesis' pathways were observed under alkali stress. Many genes in the 'Carbon fixation in photosynthetic organisms' pathway in salt stress and alkali stress were down-regulated. Metabolome showed that 431 and 378 differentially accumulated metabolites (DAMs) were identified in salt stress and alkali stress, respectively. L-Glutamic acid and 5-Aminolevulinate involved in chlorophyll synthesis decreased under salt stress and alkali stress. The abundance of 19 DAMs under salt stress related to photosynthesis decreased. The abundance of 16 organic acids in salt stress and 22 in alkali stress increased respectively. CONCLUSIONS: Our findings suggested that alkali stress had more adverse effects on grapevine leaves, chloroplast structure, ion balance, and photosynthesis than salt stress. Transcriptional and metabolic profiling showed that there were significant differences in the effects of salt stress and alkali stress on the expression of key genes and the abundance of pivotal metabolites in grapevine plants.


Assuntos
Vitis , Vitis/metabolismo , Regulação da Expressão Gênica de Plantas , Álcalis/metabolismo , Proteínas de Plantas/genética , Perfilação da Expressão Gênica , Estresse Salino/genética , Transcriptoma , Clorofila/metabolismo
10.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430224

RESUMO

Salt stress is one the most destructive abiotic stressors, causing yield losses in wheat worldwide. A prerequisite for improving salt tolerance is the identification of traits for screening genotypes and uncovering causative genes. Two populations of F3 lines developed from crosses between sensitive and tolerant parents were tested for salt tolerance at the seedling stage. Based on their response, the offspring were classified as salt sensitive and tolerant. Under saline conditions, tolerant genotypes showed lower Na+ and proline content but higher K+, higher chlorophyll content, higher K+/Na+ ratio, higher PSII activity levels, and higher photochemical efficiency, and were selected for further molecular analysis. Five stress responsive QTL identified in a previous study were validated in the populations. A QTL on the short arm of chromosome 1D showed large allelic effects in several salt tolerant related traits. An expression analysis of associated candidate genes showed that TraesCS1D02G052200 and TraesCS5B02G368800 had the highest expression in most tissues. Furthermore, qRT-PCR expression analysis revealed that ZIP-7 had higher differential expressions under saline conditions compared to KefC, AtABC8 and 6-SFT. This study provides information on the genetic and molecular basis of salt tolerance that could be useful in development of salt-tolerant wheat varieties.


Assuntos
Tolerância ao Sal , Triticum , Tolerância ao Sal/genética , Triticum/fisiologia , Estresse Salino , Genótipo , Cromossomos
11.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36430691

RESUMO

Increased soil salinity is one of the main concerns in agriculture and food production, and it negatively affects plant growth and crop productivity. In order to mitigate the adverse effects of salinity stress, plant biostimulants (PBs) have been indicated as a promising approach. Indeed, these products have a beneficial effect on plants by acting on primary and secondary metabolism and by inducing the accumulation of protective molecules against oxidative stress. In this context, the present work is aimed at comparatively investigating the effects of microbial (i.e., Azospirillum brasilense) and plant-derived biostimulants in alleviating salt stress in tomato plants by adopting a multidisciplinary approach. To do so, the morphological and biochemical effects were assessed by analyzing the biomass accumulation and root characteristics, the activity of antioxidant enzymes and osmotic stress protection. Furthermore, modifications in the metabolomic profiles of both leaves and root exudates were also investigated by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS). According to the results, biomass accumulation decreased under high salinity. However, the treatment with A. brasilense considerably improved root architecture and increased root biomass by 156% and 118% in non-saline and saline conditions, respectively. The antioxidant enzymes and proline production were enhanced in salinity stress at different levels according to the biostimulant applied. Moreover, the metabolomic analyses pointed out a wide set of processes being affected by salinity and biostimulant interactions. Crucial compounds belonging to secondary metabolism (phenylpropanoids, alkaloids and other N-containing metabolites, and membrane lipids) and phytohormones (brassinosteroids, cytokinins and methylsalicylate) showed the most pronounced modulation. Overall, our results suggest a better performance of A. brasilense in alleviating high salinity than the vegetal-derived protein hydrolysates herein evaluated.


Assuntos
Azospirillum brasilense , Lycopersicon esculentum , Lycopersicon esculentum/metabolismo , Azospirillum brasilense/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Raízes de Plantas/metabolismo , Plantas/metabolismo , Estresse Salino
12.
An Acad Bras Cienc ; 94(suppl 3): e20211117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417604

RESUMO

The object of this study can be found among the various ornamental rocks used in historic buildings in the city of Rio de Janeiro. It is a degraded Leptinito Gneiss that makes up one of the support columns of the kitchen of the Mosteiro de São Bento (Monastery of Saint Benedict) in Rio de Janeiro. The main aim of the present study is to identify the causes of the high degree of degradation of said column. Non-destructive tests were performed, and laboratory evaluation of the disintegrated fragments may help restore and conserve this column in the future. Results obtained from the tests performed on the altered column were compared to those obtained from another column in the monastery, also built in Leptinito, which is more intact and is a sound Leptinito Gneiss. The results showed that degradation of the column is caused by the crystallization of salts (halite) inside the rock, which is reducing its mechanical strength and causing an imminent risk of collapse.


Assuntos
Estresse Salino , Brasil , Cidades
13.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364324

RESUMO

In this study, Scenedesmus sp. FSP3 was cultured using a two-stage culture strategy for CO2 fixation and lutein production. During the first stage, propylene carbonate was added to the medium, with 5% CO2 introduced to promote the rapid growth and CO2 fixation of the microalgae. During the second stage of cultivation, a NaCl concentration of 156 mmol L-1 and a light intensity of 160 µmol m-2 s-1 were used to stimulate the accumulation of lutein in the microalgal cells. By using this culture method, high lutein production and CO2 fixation were simultaneously achieved. The biomass productivity and carbon fixation rate of Scenedesmus sp. FSP3 reached 0.58 g L-1 d-1 and 1.09 g L-1 d-1, with a lutein content and yield as high as 6.45 mg g-1 and 2.30 mg L-1 d-1, respectively. The results reveal a commercially feasible way to integrate microalgal lutein production with CO2 fixation processes.


Assuntos
Microalgas , Scenedesmus , Luteína , Dióxido de Carbono , Biomassa , Estresse Salino
14.
Braz J Biol ; 82: e265069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36327399

RESUMO

Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.


Assuntos
Lycopersicon esculentum , Ácido Salicílico/farmacologia , Salinidade , Estresse Salino , Água
15.
Sci Rep ; 12(1): 20439, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443368

RESUMO

Brassinolide (BR) is a sterol compound, which can regulate plant seed germination, flowering, senescence, tropism, photosynthesis, stress resistance, and is closely related to other signaling molecules. This study aimed to evaluate the ability of soaking with BR to regulate growth quality at rice seedling stage under salt stress. Results demonstrated that salt stress increases the contents of ROS, MDA, Na+ and ABA, reduces the the SPAD value, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), maximum fluorescence (Fm), variable fluorescence (Fv), the effective photochemical efficiency of PSII (Fv/Fo) and the maximum photochemical efficiency of PSII (Fv/Fm), reduces the biomass production and inhabits plant growth. All of these responses were effectively alleviated by BR soaking treatment. Soaking with BR could increase the activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and the contents of ascorbic acid, glutathione as well as soluble protein and proline, while BR soaking treatment inhibited the accumulation of ROS and reduced the content of MDA. BR soaking significantly reduced the contents of Na+ and increased the contents of K+ and Ca2+, indicating that soaking with BR is beneficial to the excretion of Na+, the absorption of K+ and Ca2+ and the maintenance of ion balance in rice seedlings under salt stress. BR also maintained endogenous hormone balance by increasing the contents of indoleacetic acid (IAA), zeatin (ZT), salicylic acid (SA), and decreasing the ABA content. Soaking with BR significantly increased the SPAD value, Pn and Tr and enhanced the Fm, Fv/Fm and Fv/Fo of rice seedlings under NaCl stress, protected the photosythetic system of plants, and improved their biomass. It is suggested that BR was beneficial to protect membrane lipid peroxidation, the modulation of antioxidant defense systems, ion balance and endogenous hormonal balance with imposition to salt stress.


Assuntos
Oryza , Plântula , Espécies Reativas de Oxigênio , Estresse Salino
16.
World J Microbiol Biotechnol ; 38(12): 253, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36316429

RESUMO

Salt stress is one of the major abiotic stresses that severely affect plant growth and yield, and also affect the livelihood of people all around the world. Arbuscular mycorrhizal fungi (AMF) colonize majority of terrestrial plants, including halophytes, xerophytes and glycophytes, and facilitate their functioning by various physiological, biochemical and molecular processes. In the past two decades, significant progress has been made to understand the role of AMF in mitigating salt stress and improving plant growth and productivity under saline conditions. Several studies focusing on the biochemical and physiological mechanisms that mycorrhizal plants employ to combat salt stress have been carried out. This review reinforces such studies and gives further insights into the molecular aspects of tolerance to salt stress in the plants colonized by AMF. It emphasises on the role of AMF in sensing and signalling salt stress, expression of aquaporin-encoding genes, Na+/H+ antiporters and transporters involved in Na+ exclusion, CNGCs and late embryogenesis abundant proteins in relation to salt stress tolerance. Further, this paper also reviews the accrual of compatible osmolytes, phytohormones and nitric oxide for understanding the benefits of this symbiosis under saline environment, and provides a benchmark information to understand the contribution of mycorrhizal symbiosis at molecular level and will attract attention of researchers to develop and highlight the future research programs in this field.


Assuntos
Micorrizas , Humanos , Micorrizas/fisiologia , Tolerância ao Sal , Estresse Salino , Simbiose , Plantas Tolerantes a Sal/genética
17.
BMC Genomics ; 23(1): 735, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316643

RESUMO

BACKGROUND: Soil salinity is a problem in more than 100 countries across all continents. It is one of the abiotic stress that threatens agriculture the most, negatively affecting crops and reducing productivity. Transcriptomics is a technology applied to characterize the transcriptome in a cell, tissue, or organism at a given time via RNA-Seq, also known as full-transcriptome shotgun sequencing. This technology allows the identification of most genes expressed at a particular stage, and different isoforms are separated and transcript expression levels measured. Once determined by this technology, the expression profile of a gene must undergo validation by another, such as quantitative real-time PCR (qRT-PCR). This study aimed to select, annotate, and validate stress-inducible genes-and their promoters-differentially expressed in the leaves of oil palm (Elaeis guineensis) plants under saline stress. RESULTS: The transcriptome analysis led to the selection of 14 genes that underwent structural and functional annotation, besides having their expression validated using the qRT-PCR technique. When compared, the RNA-Seq and qRT-PCR profiles of those genes resulted in some inconsistencies. The structural and functional annotation analysis of proteins coded by the selected genes showed that some of them are orthologs of genes reported as conferring resistance to salinity in other species. There were those coding for proteins related to the transport of salt into and out of cells, transcriptional regulatory activity, and opening and closing of stomata. The annotation analysis performed on the promoter sequence revealed 22 distinct types of cis-acting elements, and 14 of them are known to be involved in abiotic stress. CONCLUSION: This study has helped validate the process of an accurate selection of genes responsive to salt stress with a specific and predefined expression profile and their promoter sequence. Its results also can be used in molecular-genetics-assisted breeding programs. In addition, using the identified genes is a window of opportunity for strategies trying to relieve the damages arising from the salt stress in many glycophyte crops with economic importance.


Assuntos
Arecaceae , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Estresse Salino/genética , Perfilação da Expressão Gênica , Arecaceae/genética , Transcriptoma
18.
BMC Plant Biol ; 22(1): 479, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209052

RESUMO

BACKGROUND: As the king of all herbs, the medicinal value of ginseng is self-evident. The perennial nature of ginseng causes its quality to be influenced by various factors, one of which is the soil environment. During plant growth and development, MYB transcription factors play an important role in responding to abiotic stresses and regulating the synthesis of secondary metabolites. However, there are relatively few reports on the MYB transcription factor family in Panax ginseng. RESULTS: This study identified 420 PgMYB transcripts under 117 genes ID in the Jilin ginseng transcriptome database. Phylogenetic analysis showed that PgMYB transcripts in Jilin ginseng were classified into 19 functional subclasses. The GO annotation result indicated that the functional differentiation of PgMYB transcripts was annotated to 11 functional nodes at GO Level 2 in ginseng. Expression pattern analysis of PgMYB transcripts based on the expression data (TPM) that PgMYB transcripts were revealed spatiotemporally specific in expression patterns. We performed a weighted network co-expression network analysis on the expression of PgMYB transcripts from different samples. The co-expression network containing 51 PgMYB transcripts was formed under a soft threshold of 0.85, revealing the reciprocal relationship of PgMYB in ginseng. Treatment of adventitious roots of ginseng with different concentrations of NaCl revealed four up-regulated expression of PgMYB transcripts that can candidate genes for salt resistance studies in ginseng. CONCLUSIONS: The present findings provide data resources for the subsequent study of the functions of MYB transcription factor family members in ginseng, and provide an experimental basis for the anti-salt functions of MYB transcription factors in Panax ginseng.


Assuntos
Panax , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Panax/genética , Panax/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Salino/genética , Cloreto de Sódio/metabolismo , Solo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Int J Mol Sci ; 23(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36232881

RESUMO

As one of the largest transcription factor families in plants, bZIP transcription factors play important regulatory roles in different biological processes, especially in the process of stress response. Salt stress inhibits the growth and yield of sugar beet. However, bZIP-related studies in sugar beet (Beta vulgaris L.) have not been reported. This study aimed to identify the bZIP transcription factors in sugar beet and analyze their biological functions and response patterns to salt stress. Using bioinformatics, 48 BvbZIP genes were identified in the genome of sugar beet, encoding 77 proteins with large structural differences. Collinearity analysis showed that three pairs of BvbZIP genes were fragment replication genes. The BvbZIP genes were grouped according to the phylogenetic tree topology and conserved structures, and the results are consistent with those reported in Arabidopsis. Under salt stress, the expression levels of most BvbZIP genes were decreased, and only eight genes were up-regulated. GO analysis showed that the BvbZIP genes were mainly negatively regulated in stress response. Protein interaction prediction showed that the BvbZIP genes were mainly involved in light signaling and ABA signal transduction, and also played a certain role in stress responses. In this study, the structures and biological functions of the BvbZIP genes were analyzed to provide foundational data for further mechanistic studies and for facilitating the efforts toward the molecular breeding of stress-resilient sugar beet.


Assuntos
Arabidopsis , Beta vulgaris , Arabidopsis/genética , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Salino/genética , Estresse Fisiológico/genética , Açúcares/metabolismo , Fatores de Transcrição/metabolismo
20.
BMC Plant Biol ; 22(1): 502, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36289462

RESUMO

BACKGROUND: Soil salinization has become a global problem restricting the seed yield and quality of crops, including wheat (Triticum aestivum L.). Salinity significantly alters plant morphology and severely disrupts physiological homeostasis. Salt tolerance of wheat has been widely studied whereas core ion transporters responsive to salt stress remain elusive. RESULTS: In this study, the wheat seedlings were subjected to salinity toxicity for morpho-physiological and transcriptomic analysis of wheat salt tolerance. There was a inversely proportional relationship between salt concentrations and morpho-physiological parameters. Under the condition of 100 mM NaCl, the H2O2, O2-, MDA content and membrane permeability were significantly increased whereas the chlorophyll content was markedly decreased. Under salt stress, a larger proportion of Na+ was partitioned in the roots than in the shoots, which had a lower Na+/K+ ratio and proline content. Salt stress also obviously affected the homeostasis of other cations. Genome-wide transcriptomic analysis showed that a total of 2,807 and 5,570 differentially expressed genes (DEGs) were identified in the shoots and roots, respectively. Functionality analysis showed that these DEGs were mainly enriched in the KEGG pathways related to carbon metabolism, phenylalanine, and amino acid biosynthesis, and were primarily enriched in the GO terms involving proline metabolism and redox processes. The Na+ transporter genes were upregulated under salt stress, which repressed the gene expression of the K+ transporters. Salt stress also significantly elevated the expression of the genes involved in osmoregulation substances biosynthesis, and obviously affected the expression profiling of other cation transporters. Co-expression network analysis identified TaNHX6-D5/TaNHX4-B7 and TaP5CS2-B3 potentially as core members regulating wheat salt tolerance. CONCLUSIONS: These results might help us fully understand the morpho-physiological and molecular responses of wheat seedlings to salt stress, and provide elite genetic resources for the genetic modification of wheat salt tolerance.


Assuntos
Plântula , Triticum , Triticum/metabolismo , Plântula/genética , Plântula/metabolismo , Osmorregulação , Peróxido de Hidrogênio/metabolismo , Cloreto de Sódio/metabolismo , Estresse Salino/genética , Salinidade , Sódio/metabolismo , Clorofila/metabolismo , Prolina/metabolismo , Carbono/metabolismo , Nutrientes , Solo , Fenilalanina/metabolismo , Aminoácidos/metabolismo , Estresse Fisiológico/genética
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