RESUMO
In this study, we explore the interplay between the plant hormones gibberellins (GA), brassinosteroids (BR), and Indole-3-Acetic Acid (IAA) in their collective impact on plant shade avoidance elongation under varying light conditions. We focus particularly on low Red:Far-red (R:FR) light conditions achieved by supplementing the background light with FR. We characterized the tomato internode response to low R:FR and, with RNA-seq analysis, we were able to identify some of the potential regulatory hormonal pathways. Through a series of exogenous pharmacological modulations of GA, IAA, and BR, we demonstrate that GA and BR are sufficient but also necessary for inducing stem elongation under low R:FR light conditions. Intriguingly, while IAA alone shows limited effects, its combination with GA yields significant elongation, suggesting a nuanced hormonal balance. Furthermore, we unveil the complex interplay of these hormones under light with low R:FR, where the suppression of one hormone's effect can be compensated by the others. This study provides insights into the hormonal mechanisms governing plant adaptation to light, highlighting the intricate and adaptable nature of plant growth responses. Our findings have far-reaching implications for agricultural practices, offering potential strategies for optimizing plant growth and productivity in various lighting environments.
Assuntos
Brassinosteroides , Giberelinas , Ácidos Indolacéticos , Luz , Reguladores de Crescimento de Plantas , Solanum lycopersicum , Giberelinas/metabolismo , Brassinosteroides/metabolismo , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/efeitos da radiação , Solanum lycopersicum/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Luz VermelhaRESUMO
The effect of humic acid extracted from peat (AHt) on improving the struvite (STR) fertilizing efficiency is explored. To this end, a soil incubation study is correlated to plant assays comparing STR, STR-AHt, and superphosphate (SSP). Characterization techniques confirm the incorporation of the AHt into the STR. The P-pool distribution of STR and SSP is similar in the soil incubation, with STR-AHt presenting a higher labile P at 90 days passing from 10 to 15% P from SSP and STR to 25% P with STR-AHt. However, when applied to barley and tomato, STR yields more shoot P content, aboveground biomass, and residual P in soil than SSP. STR-AHt does not improve the STR results. The poor correlation observed between soil incubation and plant trials highlights the role of the rhizosphere in testing the fertilizer efficiency of STR. Mechanistic assays indicate the key role of rhizosphere pH. Finally, molecular modeling reveals a higher stabilization of STR with AHt, which could reduce P release decreasing the fertilizing potential of STR-AHt, as observed in the pot trials.
Assuntos
Fertilizantes , Substâncias Húmicas , Fosfatos , Solo , Solanum lycopersicum , Estruvita , Fertilizantes/análise , Solo/química , Substâncias Húmicas/análise , Estruvita/química , Fosfatos/química , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Hordeum/química , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Concentração de Íons de Hidrogênio , Fósforo/química , Fósforo/análise , Fósforo/metabolismo , Rizosfera , BiomassaRESUMO
Nitrogen deficiency in low organic matter soils significantly reduces crop yield and plant health. The effects of foliar applications of indole acetic acid (IAA), trehalose (TA), and nanoparticles-coated urea (NPCU) on the growth and physiological attributes of tomatoes in nitrogen-deficient soil are not well documented in the literature. This study aims to explore the influence of IAA, TA, and NPCU on tomato plants in nitrogen-deficient soil. Treatments included control, 2mM IAA, 0.1% TA, and 2mM IAA + 0.1% TA, applied with and without NPCU. Results showed that 2mM IAA + 0.1% TA with NPCU significantly improved shoot length (~ 30%), root length (~ 63%), plant fresh (~ 48%) and dry weight (~ 48%), number of leaves (~ 38%), and leaf area (~ 58%) compared to control (NPCU only). Additionally, significant improvements in chlorophyll content, total protein, and total soluble sugar, along with a decrease in antioxidant activity (POD, SOD, CAT, and APX), validated the effectiveness of 2mM IAA + 0.1% TA with NPCU. The combined application of 2mM IAA + 0.1% TA with NPCU can be recommended as an effective strategy to enhance tomato growth and yield in nitrogen-deficient soils. This approach can be integrated into current agricultural practices to improve crop resilience and productivity, especially in regions with poor soil fertility. To confirm the efficacy of 2mM IAA + 0.1% TA with NPCU in various crops and climatic conditions, additional field studies are required.
Assuntos
Ácidos Indolacéticos , Nitrogênio , Solo , Solanum lycopersicum , Trealose , Ureia , Óxido de Zinco , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/metabolismo , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Nitrogênio/metabolismo , Solo/química , Trealose/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Nanopartículas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , FertilizantesRESUMO
Due to the fast-changing global climate, conventional agricultural systems have to deal with more unpredictable and harsh environmental conditions leading to compromise food production. The application of phytonanotechnology can ensure safer and more sustainable crop production, allowing the target-specific delivery of bioactive molecules with great and partially explored positive effects for agriculture, such as an increase in crop production and plant pathogen reduction. In this study, the effect of free pterostilbene (PTB) and poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) loaded with pterostilbene was investigated on Solanum lycopersicum L. metabolism. An untargeted NMR-based metabolomics approach was used to examine primary and secondary metabolism whereas a targeted HPLC-MS/MS-based approach was used to explore the impact on defense response subjected to anti-oxidant effect of PTB, such as free fatty acids, oxylipins and them impact on hormone biosynthesis, in particular salicylic and jasmonic acid. In tomato leaves after treatment with PTB and PLGA NPs loaded with PTB (NPs + PTB), both NPs + PTB and free PTB treatments increased GABA levels in tomato leaves. In addition, a decrease of quercetin-3-glucoside associated with the increase in caffeic acid was observed suggesting a shift in secondary metabolism towards the biosynthesis of phenylpropanoids and other phenolic compounds. An increase of behenic acid (C22:0) and a remodulation of oxylipin metabolism deriving from the linoleic acid (i.e. 9-HpODE, 13-HpODE and 9-oxo-ODE) and linolenic acid (9-HOTrE and 9-oxoOTrE) after treatment with PLGA NPs and PLGA NPs + PTB were also found as a part of mechanisms of plant redox modulation. To the best of our knowledge, this is the first study showing the role of PLGA nanoparticles loaded with pterostilbene in modulating leaf metabolome and physiology in terms of secondary metabolites, fatty acids, oxylipins and hormones. In perspective, PLGA NPs loaded with PTB could be used to reshape the metabolic profile to allow plant to react more quickly to stresses.
Assuntos
Nanopartículas , Oxilipinas , Folhas de Planta , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solanum lycopersicum , Estilbenos , Nanopartículas/química , Oxilipinas/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Estilbenos/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Metabolômica/métodosRESUMO
One of the main abiotic stresses that affect plant development and lower agricultural productivity globally is salt in the soil. Organic amendments, such as compost and biochar can mitigate the opposing effects of soil salinity (SS) stress. The purpose of this experiment was to look at how tomato growth and yield on salty soil were affected by mineral fertilization and manure-biochar compost (MBC). Furthermore, the study looked at how biochar (organic amendments) work to help tomato plants that are stressed by salt and also a mechanism by which biochar addresses the salt stress on tomato plants. Tomato yield and vegetative growth were negatively impacted by untreated saline soil, indicating that tomatoes are salt-sensitive. MBC with mineral fertilization increased vegetative growth, biomass yield, fruit yield, chlorophyll, and nutrient contents, Na/K ratio of salt-stressed tomato plants signifies the ameliorating effects on tomato plant growth and yield, under salt stress. Furthermore, the application of MBC with mineral fertilizer decreased H2O2, but increased leaf relative water content (RWC), leaf proline, total soluble sugar, and ascorbic acid content and improved leaf membrane damage, in comparison with untreated plants, in response to salt stress. Among the composting substances, T7 [poultry manure-biochar composting (PBC) (1:2) @ 3 t/ha + soil-based test fertilizer (SBTF)] dose exhibited better-improving effects on salt stress and had maintained an order of T7 > T9 > T8 > T6 in total biomass and fruit yield of tomato. These results suggested that MBC might mitigate the antagonistic effects of salt stress on plant growth and yield of tomatoes by improving osmotic adjustment, antioxidant capacity, nutrient accumulation, protecting photosynthetic pigments, and reducing ROS production and leaf damage in tomato plant leaves.
Assuntos
Esterco , Fotossíntese , Estresse Salino , Solo , Solanum lycopersicum , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Solo/química , Compostagem/métodos , Osmorregulação , Fertilizantes , Salinidade , Homeostase , Clorofila/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Biomassa , Carvão VegetalRESUMO
BACKGROUND: Phosphorus-solubilizing bacteria (PSB) are vital in converting insoluble phosphorus into a soluble form that plants can readily absorb and utilize in soil. While previous studies have mainly focused on the extracellular secretion of microorganisms, few have explored the intricate intracellular metabolic processes involved in PSB-mediated phosphorus solubilization. RESULTS: Here, we uncovered that Ca3(PO4)2 could serve as a source of insoluble phosphorus for the PSB, Pseudomonas sp. NK2. High-performance liquid chromatography (HPLC) results indicated higher levels of organic acids released from insoluble phosphorus compared to a soluble phosphorus source (KH2PO4), with acetic acid released exclusively under insoluble phosphorus condition. Moreover, non-target metabolomics was employed to delve into the intracellular metabolic profile. It unveiled that insoluble phosphorus significantly enhanced the tricarboxylic acid cycle, glycolysis, glyoxylic acid metabolism, and other pathways, leading to the production of acetic acid, gluconic acid, oxalic acid, and citric acid for insoluble phosphorus solubilization. In our quest to identify suitable biochar carriers, we assessed seven types of biochar through the conjoint analysis of NBRIP medium culture and application to soil for 30 days, with cotton straw-immobilized NK2 emerging as the most potent phosphorus content provider. Lastly, NK2 after cotton straw immobilization demonstrated the ability to enhance biomass, plant height, and root development of Solanum lycopersicum L. cv. Micro Tom. CONCLUSIONS: Pseudomonas sp. NK2 with cotton straw biochar could enhance phosphorus availability and tomato growth. These findings bear significant implications for the practical application of phosphorus-solubilizing bacteria in agricultural production and the promotion of environmentally sustainable farming practices.
Assuntos
Carvão Vegetal , Fósforo , Pseudomonas , Solanum lycopersicum , Fósforo/metabolismo , Pseudomonas/metabolismo , Pseudomonas/crescimento & desenvolvimento , Solanum lycopersicum/microbiologia , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Carvão Vegetal/química , Microbiologia do Solo , Estresse Fisiológico , SolubilidadeRESUMO
Whether earthworm mucus affects Cd transport behavior in soil-plant systems remains uncertain. Consequently, this study thoroughly assessed the impacts of earthworm mucus on plant growth and physiological responses, plant Cd accumulation, translocation, and distribution, as well as soil characteristics and Cd fractionation in a soil-plant (tomato seedling) system. Results demonstrated that the earthworm inoculation considerably enhanced plant Cd uptake and decreased plant Cd translocation, the effects of which were appreciably less significant than those of the earthworm mucus. This suggested that earthworm mucus may play a crucial role in the way earthworms influence plant Cd uptake and translocation. Moreover, the artificial mucus, which contained identical inorganic nitrogen contents to those in earthworm mucus, had no significant effect on plant Cd accumulation or translocation, implying that components other than inorganic nitrogen in the earthworm mucus may have contributed significantly to the overall effects of the mucus. Compared with the control, the earthworm mucus most substantially increased the root Cd content, the Cd accumulation amount of root and whole plant, and root Cd BCF by 93.7 %, 221.3 %, 72.2 %, and 93.7 %, respectively, while notably reducing the Cd TF by 48.2 %, which may be ascribed to the earthworm mucus's significant impacts on tomato seedling growth and physiological indicators, its considerable influences on the subcellular components and chemical species of root Cd, and its substantial effects on the soil characteristics and soil Cd fractionation, as revealed by correlation analysis. Redundancy analysis further suggested that the most prominent impacts of earthworm mucus may have been due to its considerable reduction of soil pH, improvement of soil DOC content, and enhancement of the exchangeable Cd fraction in soil. This work may help better understand how earthworm mucus influences the transport behavior of metals in soil-plant systems.
Assuntos
Cádmio , Muco , Oligoquetos , Plântula , Poluentes do Solo , Solo , Solanum lycopersicum , Oligoquetos/metabolismo , Oligoquetos/fisiologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Cádmio/metabolismo , Animais , Poluentes do Solo/metabolismo , Plântula/metabolismo , Plântula/crescimento & desenvolvimento , Solo/química , Muco/metabolismoRESUMO
BACKGROUND: Plants are designed to endure stress, but increasingly extreme weather events are testing the limits. Events like flooding result in submergence of plant organs, triggering an energy crisis due to hypoxia and threaten plant growth and productivity. Lipids are relevant as building blocks and energy vault and are substantially intertwined with primary metabolism, making them an ideal readout for plant stress. RESULTS: By high resolution mass spectrometry, a distinct, hypoxia-related lipid composition of Solanum lycopersicum root tissue was observed. Out of 491 lipid species, 11 were exclusively detected in this condition. Among the lipid classes observed, glycerolipids and glycerophospholipids dominated by far (78%). Differences between the lipidomic profiles of both analyzed conditions were significantly driven by changes in the abundance of triacylglycerols (TGs) whereas sitosterol esters, digalactosyldiacylglycerols, and phosphatidylcholine play a significantly negligible role in separation. Alongside, an increased level of polyunsaturation was observed in the fatty acid chains, with 18:2 and 18:3 residues showing a significant increase. Of note, hexadecatetraenoic acid (16:4) was identified in hypoxia condition samples. Changes in gene expression of enzymes related to lipid metabolism corroborate the above findings. CONCLUSION: To our knowledge, this is the first report on a hypoxia-induced increase in TG content in tomato root tissue, closing a knowledge gap in TG abiotic stress response. The results suggest that the increase in TGs and TG polyunsaturation degree are common features of hypoxic response in plant roots.
Assuntos
Raízes de Plantas , Solanum lycopersicum , Triglicerídeos , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Raízes de Plantas/metabolismo , Triglicerídeos/metabolismo , Metabolismo dos Lipídeos , LipidômicaRESUMO
BACKGROUND: To counteract soil degradation, it is important to convert conventional agricultural practices to environmentally sustainable management practices. To this end, the application of biostimulants could be considered a good strategy. Compost, produced by the composting of biodegradable organic compounds, is a source of natural biostimulants, such as humic acids, which are naturally occurring organic compounds that arise from the decomposition and transformation of organic residues, and compost tea, a compost-derived liquid formulated produced by compost water-phase extraction. This study aimed to determine the molecular responses of the roots of tomato plants (cv. Crovarese) grown under hydroponic conditions and subjected to biostimulation with humic substances (HSs) and filtered sterile compost tea (SCT). RESULTS: The 13C CPMAS NMR of humic acids (HA) and SCT revealed strong O-alkyl-C signals, indicating a high content of polysaccharides.Thermochemolysis identified over 100 molecules, predominantly from lignin, fatty acids, and biopolymers. RNA-Seq analysis of tomato roots treated with HA or SCT revealed differentially expressed genes (DEGs) with distinct patterns of transcriptional reprogramming. Notably, HA treatment affected carbohydrate metabolism and secondary metabolism, particularly phenylpropanoids and flavonoids, while SCT had a broader impact on hormone and redox metabolism. Both biostimulants induced significant gene expression changes within 24 h, including a reduction in cell wall degradation activity and an increase in the expression of hemicellulose synthesis genes, suggesting that the treatments prompted proactive cell wall development. CONCLUSIONS: The results demonstrate that HS and SCT can mitigate stress by activating specific molecular mechanisms and modifying root metabolic pathways, particularly those involved in cell wall synthesis. However, gene regulation in response to these treatments is complex and influenced by various factors. These findings highlight the biostimulatory effects of HS and SCT, suggesting their potential application in crop biofertilization and the development of innovative breeding strategies to maximize the benefits of humic substances for crops. Further research is needed to fully elucidate these mechanisms across various contexts and plant species.
Assuntos
Compostagem , Substâncias Húmicas , Raízes de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacosRESUMO
Enhancing drought tolerance in crops and understanding the underlying mechanisms have been subject of intense research. The precise function and molecular mechanisms of B-box zinc finger proteins (BBX) remain elusive. Here, we report a natural allele of BBX18 (BBX18TT) that encodes a C-terminal truncated protein. While most wild tomato germplasms contain the BBX18CC allele and show more drought tolerant, modern cultivated tomatoes mostly carry BBX18TT allele and are more drought sensitive. Knockout of BBX18 leads to improved drought tolerance in transgenic plants of cultivated tomato. Ascorbate peroxidase 1 (APX1) is identified as a BBX18-interacting protein that acts as a positive regulator of drought resistance in tomato. Chromatin immunoprecipitation sequencing analyses reveal that BBX18 binds to a unique cis-acting element of the APX1 promoter and represses its gene expression. This study provides insights into the molecular mechanism underlying drought resistance mediated by the BBX18-APX1 module in plants.
Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Solanum lycopersicum , Fatores de Transcrição , Dedos de Zinco , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Dedos de Zinco/genética , Regiões Promotoras Genéticas/genética , Ascorbato Peroxidases/metabolismo , Ascorbato Peroxidases/genética , AlelosRESUMO
Abiotic stresses, such as drought, salinity, and extreme temperatures, limit plant growth and development, reducing crop yields. Therefore, a more comprehensive understanding of the signaling mechanisms and responses of plants to changing environmental conditions is crucial for improving sustainable agricultural productivity. Chemical screening was conducted to find novel small compounds that act as regulators of the abiotic stress signaling pathway using the ABA-inducible transgenic reporter line. Small molecules called stress response regulators (SRRs) were isolated by screening a synthetic library composed of 14,400 small compounds, affecting phenotypes such as seed germination, root growth, and gene expression in response to multiple abiotic stresses. Seeds pretreated with SRR compounds positively affected the germination rate and radicle emergence of Arabidopsis and tomato plants under abiotic stress conditions. The SRR-priming treatment enhanced the transcriptional responses of abiotic stress-responsive genes in response to subsequent salt stress. The isolation of the novel molecules SRR1 and SRR2 will provide a tool to elucidate the complex molecular networks underlying the plant stress-tolerant responses.
Assuntos
Arabidopsis , Regulação da Expressão Gênica de Plantas , Germinação , Transdução de Sinais , Estresse Fisiológico , Estresse Fisiológico/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Bibliotecas de Moléculas Pequenas/farmacologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismoRESUMO
Ascorbic acid (AsA), an essential non-enzymatic antioxidant in plants, regulates development growth and responses to abiotic and biotic stresses. However, research on AsA's role in cold tolerance remains largely unknown. Here, our study uncovered the positive role of AsA in improving cold stress tolerance in tomato seedlings. Physiological analysis showed that AsA significantly enhanced the enzyme activity of the antioxidant defense system in tomato seedling leaves and increased the contents of proline, sugar, abscisic acid (ABA), and endogenous AsA. In addition, we found that AsA is able to protect the photosynthetic system of tomato seedlings, thereby relieving the declining rate of chlorophyll fluorescence parameters. qRT-PCR analysis indicated that AsA significantly increased the expression of genes encoding antioxidant enzymes and involved in AsA synthesis, ABA biosynthesis/signal transduction, and low-temperature responses in tomato. In conclusion, the application of exogenous AsA enhances cold stress tolerance in tomato seedlings through various molecular and physiological responses. This provides a theoretical foundation for exploring the regulatory mechanisms underlying cold tolerance in tomato and offers practical guidance for enhancing cold tolerance in tomato cultivation.
Assuntos
Ácido Ascórbico , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Plântula , Solanum lycopersicum , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/fisiologia , Ácido Ascórbico/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Temperatura Baixa , Antioxidantes/metabolismo , Clorofila/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genéticaRESUMO
Contamination of agricultural products with Cadmium (Cd) is a global problem that should be considered for minimizing the risks to human health. Considering the potential effects of SiNPs in decreasing abiotic stress, a study was conducted to investigate the effect of SiNPs in the reduction of Cd stress on Solanum lycopersicum. SiNPs was used at 0, 25, 50 and 100 mg/l and CdCl2 at 0, 100 and 200 µM concentrations. The results showed that Cd stress caused a significant decrease in dry weight, content of GSH, ASA, significently increasing the activity of GR, APX, GST, SOD, as well as content of H2O2, MDA, proline, and GABA in shoots and roots compared to the control. SiNPs significantly increased shoot and root dry weight compared to the control. As a coenzyme, SiNPs induced the activity of antioxidant enzymes and significantly increased GST and GR gene expression compared to the control. SiNPs also caused a substantial increase in the content of ASA, GSH, proline and GABA compared to the control. By inducing the activity of antioxidant enzymes and metabolites of the ascorbate-glutathione (ASA-GSH) cycle, SiNPs removed a large content of H2O2 and significantly reduced the MDA content, and as a result led to the stability of cell membrane under Cd stress. Induction of ASA-GSH, GABA and SOD cycle by SiNPs clearly showed that SiNPs could be a potential tool to alleviate Cd stress in plants cultivated in areas contaminated with this heavy metal.
Assuntos
Cádmio , Glutationa , Silício , Solanum lycopersicum , Estresse Fisiológico , Ácido gama-Aminobutírico , Glutationa/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo , Silício/farmacologia , Silício/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Antioxidantes/metabolismo , Nanopartículas/química , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácido Ascórbico/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacosRESUMO
Understanding the trophic transfer and ecological cascade effects of nanofertilizers and nanopesticides in terrestrial food chains is crucial for assessing their nanotoxicity and environmental risks. Herein, the trophic transfer of La2O3 (nLa2O3) and CuO (nCuO) nanoparticles from tomato leaves to Helicoverpa armigera (Lepidoptera: Noctuidae) caterpillars and their subsequent effects on caterpillar growth and intestinal health were investigated. We found that 50 mg/L foliar nLa2O3 and nCuO were transferred from tomato leaves to H. armigera, with particulate trophic transfer factors of 1.47 and 0.99, respectively. While nCuO exposure reduced larval weight gain more (34.7%) than nLa2O3 (11.3%), owing to higher oxidative stress (e.g., MDA and H2O2) and more serious intestinal pathological damage (i.e., crumpled columnar cell and disintegrated goblet cell) by nCuO. Moreover, nCuO exposure led to a more compact antagonism between the phyllosphere and gut microbiomes compared to nLa2O3. Specifically, nCuO exposure resulted in a greater increase in pathogenic bacteria (e.g., Mycobacterium, Bacillus, and Ralstonia) and a more significant decrease in probiotics (e.g., Streptomyces and Arthrobacter) than nLa2O3, ultimately destroying larval intestinal immunity. Altogether, our findings systematically revealed the cascade effect of metal oxide nanomaterials on higher trophic consumers through alteration in the phyllosphere and insect gut microbiome interaction, thus providing insights into nanotoxicity and environmental risk assessment of nanomaterials applied in agroecosystems.
Assuntos
Cadeia Alimentar , Microbioma Gastrointestinal , Nanopartículas Metálicas , Estresse Oxidativo , Solanum lycopersicum , Animais , Solanum lycopersicum/microbiologia , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Nanopartículas Metálicas/química , Mariposas/efeitos dos fármacos , Mariposas/microbiologia , Óxidos/química , Óxidos/farmacologia , Folhas de Planta/metabolismo , Cobre/farmacologia , Cobre/química , Helicoverpa armigeraRESUMO
Traditional substrate cultivation is now a routine practice in vegetable facility breeding. However, finding renewable substrates that can replace traditional substrates is urgent in today's production. In this study, we used the 'Pindstrup' substrate as control and two types of composite substrates made from fermented corn straw (i.e. 0-3 and 3-5 mm) to identify appropriate substrate conditions for tomato seedling growth under winter greenhouse conditions. Seedling growth potential related data and substrate water content related data were tested to carry out data-oriented support. Since the single physiological data cannot well explain the mechanism of tomato seedlings under winter greenhouse condition, transcriptomic analysis of tomato root and leaf tissues were conducted to provide theoretical basis. The physiological data of tomato seedlings and substrate showed that compared with 0-3 mm and Pindstrup substrate, tomato seedlings planted in 3-5 mm had stronger growth potential and stronger water retention, and were more suitable for planting tomato seedlings. Transcriptome analysis revealed a greater number of DEGs between the Pindstrup and the 3-5 mm. The genes in this group contribute to tomato growth as well as tomato stress response mechanisms, such as ABA-related genes, hormone-related genes and some TFs. The simulation network mechanism diagram adds evidence to the above conclusions. Overall, these results demonstrate the potential benefits of using the fermented corn straw of 3-5 mm for growing tomato seedlings and present a novel method of utilizing corn straw.
Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Plântula , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/genética , Plântula/metabolismo , Perfilação da Expressão Gênica/métodos , Transcriptoma , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Melhoramento Vegetal/métodos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/genéticaRESUMO
Transcription factors (TFs) are crucial for regulating fruit ripening in tomato (Solanum lycopersicum). The GRAS (GAI, RGA, and SCR) TFs are involved in various physiological processes, but their role in fruit ripening has seldom been reported. We have previously identified a gene encoding GRAS protein named SlFSR (Fruit Shelf-life Regulator), which is implicated in fruit ripening by regulating cell wall metabolism; however, the underlying mechanism remains unclear. Here, we demonstrate that SlFSR proteins are localized to the nucleus, where they could bind to specific DNA sequences. SlFSR acts downstream of the master ripening regulator RIN and could collaborate with RIN to control the ripening process by regulating expression of ethylene biosynthesis genes. In SlFSR-CR (CRISPR/Cas9) mutants, the initiation of fruit ripening was not affected but the reduced ethylene production and a delayed coloring process occurred. RNA-sequencing (RNA-seq) and promoter analysis reveal that SlFSR directly binds to the promoters of two key ethylene biosynthesis genes (SlACO1 and SlACO3) and activates their expression. However, SlFSR-CR fruits displayed a significant down-regulation of key rate-limiting genes (SlDXS1 and SlGGPPS2) in the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway, which may account for the impaired lycopene synthesis. Altogether, we propose that SlFSR positively regulates ethylene biosynthesis and lycopene accumulation, providing valuable insights into the molecular mechanisms underlying fruit ripening.
Assuntos
Etilenos , Frutas , Regulação da Expressão Gênica de Plantas , Licopeno , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Etilenos/metabolismo , Etilenos/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Frutas/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Licopeno/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Heat stress inhibits plant growth and productivity. Among the main regulators, B-box zinc-finger (BBX) proteins are well-known for their contribution to plant photomorphogenesis and responses to abiotic stress. Our research pinpoints that SlBBX31, a BBX protein harboring a conserved B-box domain, serves as a suppressor of plant growth and heat tolerance in tomato (Solanum lycopersicum L.). Overexpressing (OE) SlBBX31 in tomato exhibited yellowing leaves due to notable reduction in chlorophyll content and net photosynthetic rate (Pn). Furthermore, the pollen viability of OE lines obviously decreased and fruit bearing was delayed. This not only affected the fruit setting rate and the number of plump seeds but also influenced the size of the fruit. These results indicate that SlBBX31 may be involved in the growth process of tomato, specifically in terms of photosynthesis, flowering, and the fruiting process. Conversely, under heat-stress treatment, SlBBX31 knockout (KO) plants displayed superior heat tolerance, evidenced by their improved membrane stability, heightened antioxidant enzyme activities, and reduced accumulation of reactive oxygen species (ROS). Further transcriptome analysis between OE lines and KO lines under heat stress revealed the impact of SlBBX31 on the expression of genes linked to photosynthesis, heat-stress signaling, ROS scavenging, and hormone regulation. These findings underscore the essential role of SlBBX31 in regulating tomato growth and heat-stress resistance and will provide valuable insights for improving heat-tolerant tomato varieties.
Assuntos
Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fotossíntese , Termotolerância/genética , Espécies Reativas de Oxigênio/metabolismo , Plantas Geneticamente Modificadas/genética , Clorofila/metabolismoRESUMO
Tomato plants favor warmth, making them particularly susceptible to cold conditions, especially their reproductive development. Therefore, understanding how pollen reacts to cold stress is vital for selecting and improving cold-resistant tomato varieties. The programmed cell death (PCD) in the tapetum is particularly susceptible to cold temperatures which could hinder the degradation of the tapetal layer in the anthers, thus affecting pollen development. However, it is not clear yet how genes integral to tapetal degradation respond to cold stress. Here, we report that SlHB8, working upstream of the conserved genetic module DYT1-TDF1-AMS-MYB80, is crucial for regulating cold tolerance in tomato anthers. SlHB8 expression increases in the tapetum when exposed to low temperatures. CRISPR/Cas9-generated SlHB8-knockout mutants exhibit improved pollen cold tolerance due to the reduced temperature sensitivity of the tapetum. SlHB8 directly upregulates SlDYT1 and SlMYB80 by binding to their promoters. In normal anthers, cold treatment boosts SlHB8 levels, which then elevates the expression of genes like SlDYT1, SlTDF1, SlAMS, and SlMYB80; however, slhb8 mutants do not show this gene activation during cold stress, leading to a complete blockage of delayed tapetal programmed cell death (PCD). Furthermore, we found that SlHB8 can interact with both SlTDF1 and SlMYB80, suggesting the possibility that SlHB8 might regulate tapetal PCD at the protein level. This study sheds light on molecular mechanisms of anther adaptation to temperature fluctuations.
Assuntos
Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resposta ao Choque Frio/genética , Morte Celular/genética , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Pólen/genética , Pólen/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The bHLH transcription factors are important plant regulators against abiotic stress and involved in plant growth and development. In this study, SlALC, a gene coding for a prototypical DNA-binding protein in the bHLH family, was isolated, and SlALC-overexpression tomato (SlALC-OE) plants were generated by Agrobacterium-mediated genetic transformation. SlALC transgenic lines manifested higher osmotic stress tolerance than the wild-type plants, estimated by higher relative water content and lower water loss rate, higher chlorophyll, reducing sugar, starch, proline, soluble protein contents, antioxidant enzyme activities, and lower MDA and reactive oxygen species contents in the leaves. In SlALC-OE lines, there were more significant alterations in the expression of genes associated with stress. Furthermore, SlALC-OE fruits were more vulnerable to dehiscence, with higher water content, reduced lignin content, SOD/POD/PAL enzyme activity, and lower phenolic compound concentrations, all of which corresponded to decreased expression of lignin biosynthetic genes. Moreover, the dual luciferase reporter test revealed that SlTAGL1 inhibits SlALC expression. This study revealed that SlALC may play a role in controlling plant tolerance to drought and salt stress, as well as fruit lignification, which influences fruit dehiscence. The findings of this study have established a foundation for tomato tolerance breeding and fruit quality improvement.
Assuntos
Secas , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Tolerância ao Sal , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Tolerância ao Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Frutas/genética , Frutas/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Estresse FisiológicoRESUMO
Mechanical stimuli can affect plant growth, development, and defenses. The role of water spray stimulation, as a prevalent mechanical stimulus in the environment, in crop growth and defense cannot be overlooked. In this study, the effects of water spray on tomato plant growth and defense against the chewing herbivore Helicoverpa armigera and necrotrophic fungus Botrytis cinerea were investigated. Suprathreshold water spray stimulus (LS) was found to enhance tomato plant defenses against pests and pathogens while concurrently modifying plant architecture. The results of the phytohormone and chemical metabolite analysis revealed that LS improved the plant defense response via jasmonic acid (JA) signaling. LS significantly elevated the level of a pivotal defensive metabolite, chlorogenic acid, and reduced the emissions of volatile organic compounds (VOCs) from tomato plants, thereby defending against pest and pathogen attacks. The most obvious finding to emerge from this study is that LS enhances tomato plant defenses against biotic stresses, which will pave the way for further work on the application of mechanical stimuli for pest management.