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1.
BMC Plant Biol ; 19(1): 373, 2019 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-31445524

RESUMO

BACKGROUND: The ability of severed rootstocks and shoots to re-establish vascular connections is used to generate grafted plants that combine desirable traits from both scions and rootstocks. Clarifying the mechanisms of graft healing is essential for its further application. We performed RNA sequencing of internodes near the cut position, making a distinction between separated or grafted tissues above and below the cut, in order to obtain a genetic description of graft union formation. RESULTS: Using weighted gene co-expression analysis, variable transcripts were clustered into 10 distinct co-expression networks (modules) based on expression profiles, and genes with the most "hubness" ("hub" genes show the most connections in a network) within each module were predicted. A large proportion of modules were related to Position, and represent asymmetric expression networks from different pathways. Expression of genes involved in auxin and sugar transport and signaling, and brassinosteroid biosynthesis was increased above the cut, while stress response genes were up-regulated below the cut. Some modules were related to graft union formation, among which oxidative detoxification genes were co-expressed along with both wounding response and cell wall organization genes. CONCLUSIONS: The present work provides a comprehensive understanding of graft healing-related gene networks in tomato. Also, the candidate pathways and hub genes identified here will be valuable for future studies of grafting in tomato.


Assuntos
Lycopersicon esculentum/fisiologia , Regeneração/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Lycopersicon esculentum/genética , Raízes de Plantas/fisiologia , Transdução de Sinais
2.
BMC Plant Biol ; 19(1): 323, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319801

RESUMO

BACKGROUND: Exogenous 5-aminolevulinic acid (ALA) positively regulates plants chlorophyll synthesis and protects them against environmental stresses, although the protection mechanism is not fully clear. Here, we explored the effects of ALA on chlorophyll synthesis in tomato plants, which are sensitive to low temperature. We also examined the roles of the glutathione S-transferase (GSTU43) gene, which is involved in ALA-induced tolerance to oxidation stress and regulation of chlorophyll synthesis under low temperature. RESULTS: Exogenous ALA alleviated low temperature caused chlorophyll synthesis obstacle of uroporphyrinogen III (UROIII) conversion to protoporphyrin IX (Proto IX), and enhanced the production of chlorophyll and its precursors, including endogenous ALA, Proto IX, Mg-protoporphyrin IX (Mg-proto IX), and protochlorophyll (Pchl), under low temperature in tomato leaves. However, ALA did not regulate chlorophyll synthesis at the level of transcription. Notably, ALA up-regulated the GSTU43 gene and protein expression and increased GST activity. Silencing of GSTU43 with virus-induced gene silencing reduced the activities of GST, superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase, and increased the membrane lipid peroxidation; while fed with ALA significant increased all these antioxidase activities and antioxidant contents, and alleviated the membrane damage. CONCLUSIONS: ALA triggered GST activity encoded by GSTU43, and increased tomato tolerance to low temperature-induced oxidative stress, perhaps with the assistance of ascorbate- and/or a glutathione-regenerating cycles, and actively regulated the plant redox homeostasis. This latter effect reduced the degree of membrane lipid peroxidation, which was essential for the coordinated synthesis of chlorophyll.


Assuntos
Ácido Aminolevulínico/metabolismo , Clorofila/metabolismo , Genes de Plantas/fisiologia , Glutationa Transferase/metabolismo , Lycopersicon esculentum/genética , Proteínas de Plantas/metabolismo , Ácido Aminolevulínico/farmacologia , Resposta ao Choque Frio , Glutationa Transferase/genética , Homeostase/efeitos dos fármacos , Peroxidação de Lipídeos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/fisiologia , Oxirredução/efeitos dos fármacos , Proteínas de Plantas/genética
3.
BMC Plant Biol ; 19(1): 331, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357955

RESUMO

BACKGROUND: Salt stress is one of the environmental factors that greatly limits crop production worldwide because high salt concentrations in the soil affect morphological responses and physiological and metabolic processes, including root morphology and photosynthetic characteristics. Soil aeration has been reported to accelerate the growth of plants and increase crop yield. The objective of this study was to examine the effects of 3 NaCl salinity levels (28, 74 and 120 mM) and 3 aeration volume levels (2.3, 4.6 and 7.0 L/pot) versus non-aeration and salinity treatments on the root morphology, photosynthetic characteristics and chlorophyll content of potted tomato plants. RESULTS: The results showed that both aeration volume and salinity level affected the root parameters, photosynthetic characteristics and chlorophyll content of potted tomato plants. The total length, surface area and volume of roots increased with the increase in aeration volume under each NaCl stress level. The effect was more marked in the fine roots (especially in ≤1 mm diameter roots). Under each NaCl stress level, the photosynthetic rate and chlorophyll content of tomato significantly increased in response to the aeration treatments. The net photosynthetic rate and chlorophyll a and t content increased by 39.6, 26.9, and 17.9%, respectively, at 7.0 L/pot aeration volume compared with no aeration in the 28 mM NaCl treatment. We also found that aeration could reduce the death rate of potted tomato plants under high salinity stress conditions (120 mM NaCl). CONCLUSIONS: The results suggest that the negative effect of NaCl stress can be offset by soil aeration. Soil aeration can promote root growth and increase the photosynthetic rate and chlorophyll content, thus promoting plant growth and reducing the plant death rate under NaCl stress conditions.


Assuntos
Lycopersicon esculentum/fisiologia , Fotossíntese , Raízes de Plantas/anatomia & histologia , Clorofila/metabolismo , Lycopersicon esculentum/anatomia & histologia , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Raízes de Plantas/fisiologia , Salinidade , Estresse Salino , Solo
4.
Sci Total Environ ; 687: 601-609, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220714

RESUMO

Coastal saline soil is an important reserve land resource that has high potential for agricultural utilization. The present study adopted a high-throughput absolute quantification 16S rRNA sequencing method to investigate the effect of four different fertilization regimes (namely 100% of bio-organic fertilizer, 70% of bio-organic fertilizer +30% of chemical fertilizer, 30% of bio-organic fertilizer +70% of chemical fertilizer, and 100% of chemical fertilizer) on bacterial community assembly in a tomato cultivated saline soil. The results from the field experiment showed that a combination of 70% bio-organic fertilizer plus 30% of chemical fertilizer was the optimal dose to develop tomato cultivation (for improving yield and fruit quality) in this coastal tidal zone. The pot experiment gave the similar results on tomato growth and indicated the application of 70% bio-organic fertilizer plus 30% of chemical fertilizer as the best treatment to active the soil microbiome. The input of nutrients by fertilizers increased the total abundance of bacteria (to >3 fold compared to the initial soil) and simultaneously led to a significant loss of bacterial diversity in soil. The predominant phyla including Proteobacteria, Bacteroidetes and Firmicutes were the main contributors in the microbiome shift especially shown by their remarkable enrichment in the soil that treated by 70% of bio-organic fertilizer and those by the 100% chemical fertilizer. The RDA and Pearson correlation analyses indicated that the soil nutrient availability, especially available P and K, and soil salinity were the key environmental factors that shaped the bacterial community in this ecosystem, though the organic matter content and soil pH also played important roles in microbiome assembly.


Assuntos
Fertilizantes , Lycopersicon esculentum/fisiologia , Microbiologia do Solo , Agricultura , Monitoramento Ambiental , Salinidade , Solo/química
5.
Food Chem ; 295: 300-310, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174762

RESUMO

While fleshy fruit softening has long been mechanistically linked to cell wall disassembly, the importance of the fruit cuticle in water relations and firmness has been suggested through studies of the long-shelf life delayed fruit deterioration (dfd) tomato genotype. We tested the hypothesis that dynamic cuticle properties and composition affect tomato fruit transpiration and firmness and are influenced by environmental water availability, using dfd and two normally softening fruit cultivars, Ailsa Craig (AC) and M82, grown under control and water stress (WS) conditions. The effect of WS was also assessed following fruit detachment. WS increased fruit firmness, cuticle load, and the expression of cuticle biosynthetic genes, while reducing cuticle permeability and fruit transpiration rate in AC and M82, but not in dfd fruit. This study supports a direct relationship between fruit cuticle properties, transpiration and firmness, and provides insights into the adaptation of tomato genotypes to environments where water can be scarce.


Assuntos
Desidratação , Frutas/fisiologia , Lycopersicon esculentum/fisiologia , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Genótipo , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Transpiração Vegetal , Água/metabolismo
6.
J Microbiol Biotechnol ; 29(7): 1124-1136, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216607

RESUMO

Salinity is one of the major abiotic stresses that cause reduction of plant growth and crop productivity. It has been reported that plant growth-promoting bacteria (PGPB) could confer abiotic stress tolerance to plants. In a previous study, we screened bacterial strains capable of enhancing plant health under abiotic stresses and identified these strains based on 16s rRNA sequencing analysis. In this study, we investigated the effects of two selected strains, Bacillus aryabhattai H19-1 and B. mesonae H20-5, on responses of tomato plants against salinity stress. As a result, they alleviated decrease in plant growth and chlorophyll content; only strain H19-1 increased carotenoid content compared to that in untreated plants under salinity stress. Strains H19-1 and H20-5 significantly decreased electrolyte leakage, whereas they increased Ca2+ content compared to that in the untreated control. Our results also indicated that H20-5-treated plants accumulated significantly higher levels of proline, abscisic acid (ABA), and antioxidant enzyme activities compared to untreated and H19-1-treated plants during salinity stress. Moreover, strain H20-5 upregulated 9-cisepoxycarotenoid dioxygenase 1 (NCED1) and abscisic acid-response element-binding proteins 1 (AREB1) genes, otherwise strain H19-1 downregulated AREB1 in tomato plants after the salinity challenge. These findings demonstrated that strains H19-1 and H20-5 induced ABA-independent and -dependent salinity tolerance, respectively, in tomato plants, therefore these strains can be used as effective bio-fertilizers for sustainable agriculture.


Assuntos
Bacillus/fisiologia , Lycopersicon esculentum/fisiologia , Reguladores de Crescimento de Planta/farmacologia , Tolerância ao Sal/efeitos dos fármacos , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Fertilizantes , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Prolina/metabolismo , Estresse Salino
7.
Plant Cell Rep ; 38(9): 1151-1163, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152194

RESUMO

KEY MESSAGE: Piriformospora indica confers salt tolerance in tomato seedlings by increasing the uptake of nutrients such as N, P and Ca, improving K+/Na+ homoeostasis by regulating the expression of NHXs, SOS1 and CNGC15 genes, maintaining water status by regulating the expression of aquaporins. Piriformospora indica, an endophytic basidiomycete, has been shown to increase the growth and improve the plants tolerance to stressful conditions, especially salinity, by establishing the arbuscular mycorrhiza-like symbiotic relationship in various plant hosts. In the present research, the effect of NaCl treatment (150 mM) and P. indica inoculation on growth, accumulation of nutrients, the transcription level of genes involved in ionic homeostasis (NHXs, SOS1 and CNGC15) and regulating water status (PIP1;2, PIP2;4, TIP1;1 and TIP2;2) in roots and leaves of tomato seedlings were investigated. The P. indica improved the uptake of N, P, Ca and K, and reduced Na accumulation, and had no significant effect on Cl accumulation in roots and leaves. The endophytic fungus also increased in K+/Na+ ratio in roots and leaves of tomato by regulating the expression of NHX isoforms and upregulating SOS1 and CNGC15 expression. Salinity stress increased the transcription of PIP2;4 gene and reduced the transcription of PIP1;2, TIP1;1 and TIP2;2 genes compared to the control treatment. However, P. indica inoculation upregulated the expression of PIP1;2 and PIP2;4 genes versus non-inoculated plants but did not have a significant effect on TIP1;1 and TIP2;2 expression. These results conclude that the positive effects of P. indica on nutrients accumulation, ionic homeostasis and water status lead to the increased salinity tolerance and the improved plant growth under NaCl treatment.


Assuntos
Basidiomycota/fisiologia , Lycopersicon esculentum/microbiologia , Nutrientes/metabolismo , Potássio/metabolismo , Sódio/metabolismo , Água/metabolismo , Homeostase , Lycopersicon esculentum/genética , Lycopersicon esculentum/fisiologia , Salinidade , Tolerância ao Sal , Estresse Fisiológico , Simbiose
8.
Nat Plants ; 5(5): 471-479, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31061537

RESUMO

Genome editing technologies are being widely adopted in plant breeding1. However, a looming challenge of engineering desirable genetic variation in diverse genotypes is poor predictability of phenotypic outcomes due to unforeseen interactions with pre-existing cryptic mutations2-4. In tomato, breeding with a classical MADS-box gene mutation that improves harvesting by eliminating fruit stem abscission frequently results in excessive inflorescence branching, flowering and reduced fertility due to interaction with a cryptic variant that causes partial mis-splicing in a homologous gene5-8. Here, we show that a recently evolved tandem duplication carrying the second-site variant achieves a threshold of functional transcripts to suppress branching, enabling breeders to neutralize negative epistasis on yield. By dissecting the dosage mechanisms by which this structural variant restored normal flowering and fertility, we devised strategies that use CRISPR-Cas9 genome editing to predictably improve harvesting. Our findings highlight the under-appreciated impact of epistasis in targeted trait breeding and underscore the need for a deeper characterization of cryptic variation to enable the full potential of genome editing in agriculture.


Assuntos
Domesticação , Epistasia Genética/genética , Duplicação Gênica/genética , Lycopersicon esculentum/genética , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Flores/crescimento & desenvolvimento , Duplicação Gênica/fisiologia , Edição de Genes/métodos , Variação Genética/genética , Variação Genética/fisiologia , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/fisiologia , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Locos de Características Quantitativas/genética , Reprodução/genética , Reprodução/fisiologia
9.
BMC Plant Biol ; 19(1): 214, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31122194

RESUMO

BACKGROUND: MicroRNA319 (miR319) acts as an essential regulator of gene expression during plant development and under stress conditions. Although the role of miR319a in regulating leaf development has been well studied in tomato (Solanum lycopersicum), the function of the recently discovered wild tomato Solanum habrochaites miRNA319d (sha-miR319d) remains poorly understood. In this study, we overexpressed sha-miR319d in cultivated tomato 'Micro-Tom' to further investigate its role in tomato temperature stress responses. RESULTS: Under chilling or heat stress, sha-miR319d-overexpressing plants showed enhanced stress tolerance, including lower relative electrolyte leakage (REL), malondialdehyde (MDA) concentration, O2- generation and H2O2 concentration and higher chlorophyll contents and Fv/Fm values than wild-type (WT) plants. Overexpression of sha-miR319d enhanced the activities of superoxide dismutase (SOD) and catalase (CAT), with possible correlation with elevated expression levels of the genes FeSOD, CuZnSOD and CAT. Moreover, different expression levels of key genes involved in chilling (MYB83 and CBF1), heat (HsfA1a, HsfA1b and Hsp90), and reactive oxygen species (ROS) (ZAT12 and ZAT10) signaling in transgenic plants and WT were determined, suggesting a role for sha-miR319d in regulating tomato temperature stress via chilling, heat and ROS signaling. Silencing GAMYB-like1 increased tomato chilling tolerance as well as the expression levels of CBF1, CuZnSOD, CAT, APX1, APX2, ZAT12 and ZAT10. Additionally, overexpression of sha-miR319d in tomato caused plant leaf crinkling and reduced height. CONCLUSIONS: Overexpression of sha-miR319d confers chilling and heat stress tolerance in tomato. Sha-miR319d regulates tomato chilling tolerance, possibly by inhibiting expression of GAMYB-like1 and further alters chilling, heat and ROS signal transduction. Our research provides insight for further study of the role of sha-miR319d in tomato growth and stress regulation and lays a foundation for the genetic improvement of tomato.


Assuntos
Resposta ao Choque Frio/genética , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/genética , Lycopersicon esculentum/fisiologia , MicroRNAs/genética , RNA de Plantas/genética , Solanum/fisiologia , Lycopersicon esculentum/genética , MicroRNAs/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , RNA de Plantas/metabolismo , Solanum/genética , Termotolerância/genética
10.
BMC Plant Biol ; 19(1): 194, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077147

RESUMO

BACKGROUND: Our study is the first to provide RNA-Seq data analysis related to transcriptomic responses towards drought across different crops. The aim was to identify and map which genes play a key role in drought response on leaves across different crops. Forty-two RNA-seq samples were analyzed from 9 published studies in 7 plant species (Arabidopsis thaliana, Solanum lycopersicum, Zea mays, Vitis vinifera, Malus X domestica, Solanum tuberosum, Triticum aestivum). RESULTS: Twenty-seven (16 up-regulated and 11 down-regulated) drought-regulated genes were commonly present in at least 7 of 9 studies, while 351 (147 up-regulated and 204 down-regulated) were commonly drought-regulated in 6 of 9 studies. Across all kind of leaves, the drought repressed gene-ontologies were related to the cell wall and membrane re-structuring such as wax biosynthesis, cell wall organization, fatty acid biosynthesis. On the other hand, drought-up-regulated biological processes were related to responses to osmotic stress, abscisic acid, water deprivation, abscisic-activated signalling pathway, salt stress, hydrogen peroxide treatment. A common metabolic feature linked to drought response in leaves is the repression of terpenoid pathways. There was an induction of AL1 (alfin-like), UGKYAH (trihelix), WRKY20, homeobox genes and members of the SET domain family in 6 of 9 studies. Several genes involved in detoxifying and antioxidant reactions, signalling pathways and cell protection were commonly modulated by drought across the 7 species. The chromosome (Chr) mapping of these key abiotic stress genes highlighted that Chr 4 in Arabidopsis thaliana, Chr 1 in Zea mays, Chr 2 and Chr 5 in Triticum aestivum contained a higher presence of drought-related genes compared to the other remaining chromosomes. In seedling studies, it is worth notice the up-regulation of ERF4 and ESE3 (ethylene), HVA22 (abscisic acid), TIR1 (auxin) and some transcription factors (MYB3, MYB94, MYB1, WRKY53 and WRKY20). In mature leaves, ERF1 and Alfin-like 1 were induced by drought while other transcription factors (YABBY5, ARR2, TRFL2) and genes involved phospholipid biosynthesis were repressed. CONCLUSIONS: The identified and mapped genes might be potential targets of molecular breeding activities to develop cultivars with enhanced drought resistance and tolerance across different crops.


Assuntos
Cromossomos de Plantas/genética , Produtos Agrícolas/genética , Genes de Plantas/genética , Folhas de Planta/metabolismo , RNA de Plantas/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas/fisiologia , Desidratação , Genes de Plantas/fisiologia , Lycopersicon esculentum/genética , Lycopersicon esculentum/fisiologia , Malus/genética , Malus/fisiologia , Folhas de Planta/anatomia & histologia , RNA de Plantas/fisiologia , Solanum tuberosum/genética , Solanum tuberosum/fisiologia , Triticum/genética , Triticum/fisiologia , Vitis/genética , Vitis/fisiologia , Zea mays/genética , Zea mays/fisiologia
11.
Planta ; 250(2): 563-572, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31123806

RESUMO

MAIN CONCLUSION: This article unveiled that ethylene biosynthesis and signaling play a critical role in heat stress response of tomato plants under elevated CO2. Plant responses to elevated CO2 and heat stress are tightly regulated by an intricate network of phytohormones. Plants accumulate ethylene (ET), the smallest hormone, in response to heat stress; however, the role of ET and its signaling in elevated CO2-induced heat stress response remains largely unknown. In this study, we found that transcript levels of multiple genes relating to ET synthesis, signaling, and heat shock proteins (HSPs) were induced by elevated CO2 (800 µmol mol-1) compared to ambient CO2 (400 µmol mol-1) in tomato leaves under controlled temperature conditions (25 °C). Elevated CO2-induced responses to heat stress (42 °C) were closely associated with increased ET production and HSP70 expression at both transcript and protein levels. Pretreatment with an antagonist of ET, 1-methylcyclopropene that inhibits ET-dependent responses, abolished elevated CO2-induced stress response without affecting the ET production rate. In addition, silencing of ethylene response factor 1 (ERF1) compromised elevated CO2-induced responses to heat stress, which was associated with the concomitant reduction in the transcript of heat shock factor A2, HSP70 and HSP90, indicating that ERF1 is required for elevated CO2-induced responses to heat. All these results provide convincing evidence on the importance of ET biosynthesis and signaling in elevated CO2-induced heat stress response in tomato plants. Thus, the study advances our understanding of the mechanisms of elevated CO2-induced stress response and may potentially be useful for breeding heat-tolerant tomatoes in the era of climate change.


Assuntos
Dióxido de Carbono/farmacologia , Etilenos/biossíntese , Lycopersicon esculentum/fisiologia , Reguladores de Crescimento de Planta/biossíntese , Proteínas de Plantas/metabolismo , Transdução de Sinais , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Resposta ao Choque Térmico , Temperatura Alta , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/genética , Melhoramento Vegetal , Proteínas de Plantas/genética
12.
Planta ; 250(2): 643-655, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144110

RESUMO

MAIN CONCLUSION: Trehalose increased drought tolerance of tomato plants, accompanied by reduced water loss and closed stomata, which was associated with the upregulated ABA signaling-related genes expression, but not in ABA accumulation. Drought is one of the principal abiotic stresses that negatively influence the growth of plant and yield. Trehalose has great agronomic potential to improve the stress tolerance of plants. However, little information is available on the role of ABA and its signaling components in trehalose-induced drought tolerance. The aim of this study is to elucidate the potential mechanism by which trehalose regulates ABA in response to drought stress. In this study, 6-week-old tomato (Solanum lycopersicum cv. Ailsa Craig) plants were treated with 0 or 15.0 mM trehalose solution. Results showed that trehalose treatment significantly enhanced drought tolerance of tomato plants, accompanied by encouraged stomatal closure and protected chloroplast ultrastructure. Compared with controls, trehalose-treated plants showed lower hydrogen peroxide content and higher antioxidant enzymes activities, which contributed to alleviate oxidative damage caused by drought. Moreover, trehalose treatment decreased ABA content, which was followed by the downregulation of ABA biosynthesis genes expression and the upregulation of ABA catabolism genes expression. In contrast, exogenous trehalose upregulated transcript levels of ABA signaling-related genes, including SlPYL1/3/4/5/6/7/9, SlSnRK2.3/4, SlAREB1/2, and SlDREB1. These results suggested that trehalose treatment enhanced drought tolerance of tomato plants, and it's ABA signaling rather than ABA metabolism that was involved in trehalose-induced drought tolerance in tomato plants. These findings provide evidence for the physiological role of trehalose and bring about a new understanding of the possible relationship between trehalose and ABA.


Assuntos
Ácido Abscísico/metabolismo , Lycopersicon esculentum/fisiologia , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais , Trealose/farmacologia , Cloroplastos/fisiologia , Cloroplastos/ultraestrutura , Secas , Lycopersicon esculentum/genética , Lycopersicon esculentum/ultraestrutura , Fenótipo , Proteínas de Plantas/genética , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Estômatos de Plantas/ultraestrutura , Estresse Fisiológico
13.
Bioelectrochemistry ; 129: 70-78, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31103849

RESUMO

Plants can communicate with other plants using wireless pathways in the plant-wide web. Some examples of these communication pathways are: (1) volatile organic compounds' emission and sensing; (2) mycorrhizal networks in the soil; (3) the plants' rhizosphere; (4) naturally grafting of roots of the same species; (5) electrostatic or electromagnetic interactions; and (6) acoustic communication. There is an additional pathway for electrical signal transmission between plants - electrical signal transmission between roots through the soil. To avoid the possibility of communication between plants using mechanisms (1)-(6), soils in pots with plants were connected by Ag/AgCl or platinum wires. Electrostimulation of Aloe vera, tomato, or cabbage plants induces electrotonic potentials transmission in the electro-stimulated plants as well as the plants located in different pots regardless if plants are the same or different types. The amplitude and sign of electrotonic potentials in electrostimulated and neighboring plants depend on the amplitude, rise, and fall of the applied voltage. Experimental results displayed cell-to-cell electrical coupling and the existence of electrical differentiators in plants. Electrostimulation by a sinusoidal wave induces an electrical response with a phase shift. Electrostimulation serves as an important tool for the evaluation of mechanisms of communication in the plant-wide web.


Assuntos
Aloe/fisiologia , Brassica/fisiologia , Estimulação Elétrica , Lycopersicon esculentum/fisiologia , Aloe/citologia , Brassica/citologia , Comunicação Celular , Eletricidade , Lycopersicon esculentum/citologia , Folhas de Planta/citologia , Folhas de Planta/fisiologia , Raízes de Plantas/citologia , Raízes de Plantas/fisiologia
14.
Int J Mol Sci ; 20(8)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022849

RESUMO

Trichoderma species are fungi widely employed as plant-growth-promoting agents and for biological control. Several commercial and laboratory-made solid formulations for mass production of Trichoderma have been reported. In this study, we evaluated a solid kaolin-based formulation to promote the absortion/retention of Trichoderma asperellum in the substrate for growing tomato plants. The unique implementation of this solid formulation resulted in an increased growth of the tomato plants, both in roots and shoots after 40 days of its application. Plants were challenged with two fungal pathogens, Fusarium oxysporum and Botrytis cinerea, and pretreatment with T. asperellum resulted in less severe wilting and stunting symptoms than non-treated plants. Treatment with T. asperellum formulation inhibited Reactive Oxygen Species (ROS) production in response to the pathogens in comparison to plants that were only challenged with both pathogens. These results suggest that decrease in ROS levels contribute to the protective effects exerted by T. asperellum in tomato.


Assuntos
Botrytis/fisiologia , Fusarium/fisiologia , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Trichoderma/fisiologia , Lycopersicon esculentum/anatomia & histologia , Lycopersicon esculentum/fisiologia , Doenças das Plantas/prevenção & controle , Fatores de Proteção
15.
Planta ; 250(1): 173-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30955097

RESUMO

MAIN CONCLUSION: The overexpression of SlbHLH22 functioned in controlling flowering time, accelerated fruit ripening, and produced more ethylene-producing phenotypes in tomato. Flowering and fruit ripening are two complex transition processes regulated by various internal and external factors that ultimately lead to fruit maturation and final seed dispersal. The basic helix-loop-helix (bHLH) transcription factor is the largest TF gene family in plants that controls various biological and developmental aspects, but the actual roles of these genes have not been fully studied. Here, we performed a functional characterization of the bHLH gene SlbHLH22 in tomato. SlbHLH22 was fully expressed in tomato flowers, while a moderate expression level was also observed in fruits at different developmental stages. Overexpression of the SlbHLH22 gene revealed that it is highly involved in controlling flowering time, through the activation of the SlSFT or SlLFY genes, and promoting fruit ripening and improved carotenoid accumulation. The expression patterns of carotenoid-related genes (SlPYS1) were also upregulated in transgenic tomato fruits. In transgenic tomato fruit, we observed clear changes in colour from green to orange with enhanced expression of the SlbHLH22 gene. SlbHLH22 was upregulated under exogenous ACC, IAA, ABA, and ethephon. Overexpression of SlbHLH22 also promotes ethylene production. Moreover, ethylene biosynthesis and perception genes (SlACO3, SlACS1, SlACS2, SlACS4, SlACS1a, SlEIN1, SlEIN2, SlEIN3, SlEIN4, SlETR2, SlETR3, SlSAM3, and SlSAMS) were upregulated. Ripening-related genes (SlAP2a, SlCNR, SlNOR, SlMYB, and SlTAG) were consistent in their expression pattern in transgenic plants. Finally, our study provides evidence that tomato bHLH genes play an important role in flowering, fruit ripening, and development.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Reguladores de Crescimento de Planta/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carotenoides/metabolismo , Etilenos/metabolismo , Flores/genética , Flores/fisiologia , Frutas/genética , Frutas/fisiologia , Expressão Gênica , Lycopersicon esculentum/fisiologia , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regulação para Cima
16.
Int J Mol Sci ; 20(8)2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31010052

RESUMO

Early blight is a disease that greatly affects Solanaceae, mainly damaging tomato plants, and causing significant economic losses. Although there are methods of biological control, these are very expensive and often their mode of action is slow. Due to this, there is a need to use new techniques that allow a more efficient control of pathogens. Nanotechnology is a new alternative to solve these problems, allowing the creation of new tools for the treatment of diseases in plants, as well as the control of pathogens. The aim of the present investigation was to evaluate the foliar application of selenium and copper in the form of nanoparticles in a tomato crop infested by Alternaria solani. The severity of Alternaria solani, agronomic variables of the tomato crop, and the changes in the enzymatic and non-enzymatic antioxidant compounds were evaluated. The joint application of Se and Cu nanoparticles decreases the severity of this pathogen in tomato plants. Moreover, high doses generated an induction of the activity of the enzymes superoxide dismutase, ascorbate peroxidase, glutathione peroxidase (GPX) and phenylalanine ammonia lyase in the leaves, and the enzyme GPX in the fruit. Regarding non-enzymatic compounds in the leaves, chlorophyll a, b, and totals were increased, whereas vitamin C, glutathione, phenols, and flavonoids were increased in fruits. The application of nanoparticles generated beneficial effects by increasing the enzymatic and non-enzymatic compounds and decreasing the severity of Alternaria solani in tomato plants.


Assuntos
Alternaria/fisiologia , Cobre/farmacologia , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/fisiologia , Nanopartículas/química , Selênio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Alternaria/efeitos dos fármacos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Fenilalanina Amônia-Liase/metabolismo , Pigmentos Biológicos/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo
17.
Theor Appl Genet ; 132(7): 2125-2135, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31020387

RESUMO

KEY MESSAGE: Tomato male sterile-1526 locus was fine-mapped to an interval of 44.6 kb, and a B-class MADS-box gene TM6 was identified as the candidate gene. Male sterile lines have been widely used for hybrid seed production in many crop plants. The tomato male sterile-1526 (ms-1526) mutant displays abnormal stamens and exerted stigmas and is suitable for practical use. In this study, the ms-1526 locus was fine-mapped to a 44.6 kb interval that contained four putative genes. Thereinto, Solyc02g084630 encodes tomato B-class MADS-box gene TM6 (syn. TDR6), which plays an important role in stamen development. Sequencing revealed that there was a 12.7 kb deletion in the ms-1526 region, where the promoter and first four exons of the TM6 gene were absent. ms-1547, an allele of ms-1526, also contained the same deletion in the TM6 gene. And the other allele ms-15 mutant contained a single-nucleotide polymorphism (SNP, C to A) in the coding region of the TM6 gene, which led to a missense mutation (G to W). The codominant insertion/deletion (InDel) marker MS26D and codominant derived cleaved amplified polymorphic sequence (dCAPS) marker MS15C were developed based on the deletion and SNP, respectively. A real-time quantitative reverse-transcription PCR showed that expression of the TM6 gene was barely detectable in the flowers of the ms-1526 and ms-1547 mutants. In addition, other floral organ identity genes, pollen development marker genes, and pistil marker genes were differentially expressed between wild type and mutant flowers. These findings may facilitate functional analysis of the TM6 gene and help in the marker-assisted selection of ms-15 and its alleles in tomato breeding.


Assuntos
Flores/fisiologia , Lycopersicon esculentum/genética , Proteínas de Domínio MADS/genética , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Alelos , Mapeamento Cromossômico , Flores/genética , Marcadores Genéticos , Genótipo , Mutação INDEL , Lycopersicon esculentum/fisiologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Deleção de Sequência
18.
BMC Plant Biol ; 19(1): 100, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30866807

RESUMO

BACKGROUND: MicroRNA (miRNA) are key players in regulating expression of target genes at post-transcriptional level. A number of miRNAs are implicated in modulating tolerance to various abiotic stresses. Waterlogging is an abiotic stress that deters plant growth and productivity by hypoxia. Dozens of reports mention about the miRNAs expressed in response to waterlogging and hypoxia. Despite the fact that tomato is a model vegetable but waterlogging sensitive crop, the role of miRNAs in hypoxia tolerance is poorly understood in tomato. RESULTS: In this study, we investigated the differentially expressed miRNAs between hypoxia-treated and untreated wild tomato root by using high-throughput sequencing technology. A total of 33 known miRNAs were lowly expressed, whereas only 3 miRNAs showed higher expression in hypoxia-treated wild tomato root compared with untreated wild tomato root. Then two conserved and lowly expressed miRNAs, miR171 and miR390, were deactivated by Short Tandem Target Mimic (STTM) technology in Arabidopsis. As the results, the number and length of lateral roots were more in STTM171 and STTM390 transgenic lines compared with that of wild type plant, which partly phenocopy the increase root number and shortening the root length in hypoxia-treated wild tomato root. CONCLUSIONS: The differentially expressed miRNAs between hypoxia-treated wild tomato and control root, which contribute to the auxin homeostasis, morphologic change, and stress response, might result in reduction in the biomass and length of the root in hypoxiated conditions.


Assuntos
Ácidos Indolacéticos/metabolismo , Lycopersicon esculentum/genética , MicroRNAs/genética , Oxigênio/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Biomassa , Homeostase , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , RNA de Plantas/genética , Estresse Fisiológico
19.
Planta ; 249(6): 1779-1797, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30838445

RESUMO

MAIN CONCLUSION: In tomato, Ve1 gene expression is induced specifically by physical damage or plant wounding, resulting in a defense/stress cascade that mimics responses during Verticillium colonization and wilt. In tomato, Verticillium resistance is determined by the Ve gene locus, which encodes two leucine-rich repeat-receptor-like proteins (Ve1, Ve2); the Ve1 gene is induced differentially while Ve2 is constitutively expressed throughout disease development. These profiles have been observed even during compatible Verticillium interactions, colonization by some bacterial pathogens, and growth of transgenic tomato plants expressing the fungal Ave1 effector, suggesting broader roles in disease and/or stress. Here, we have examined further Ve gene expression in resistant and susceptible plants under abiotic stress, including a water deficit, salinity and physical damage. Using both quantitative RT-PCR and label-free LC-MS methods, changes have been evaluated at both the mRNA and protein levels. The results indicate that Ve1 gene expression responds specifically to physical damage or plant wounding, resulting in a defense/stress cascade that resembles observations during Verticillium colonization. In addition, the elimination or reduction of Ve1 or Ve2 gene function also result in proteomic responses that occur with wilt pathogen and continue to be consistent with an antagonistic relationship between the two genes. Mutational analyses also indicate the plant wounding hormone, systemin, is not required, while jasmonic acid again appears to play a direct role in induction of the Ve1 gene.


Assuntos
Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/fisiologia , Glicoproteínas de Membrana/metabolismo , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Verticillium/fisiologia , Resistência à Doença/genética , Lycopersicon esculentum/genética , Lycopersicon esculentum/imunologia , Glicoproteínas de Membrana/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteômica , RNA Mensageiro/genética , RNA de Plantas/genética , Receptores de Superfície Celular/genética , Estresse Fisiológico , Ferimentos e Lesões
20.
Pest Manag Sci ; 75(8): 2251-2263, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30701652

RESUMO

BACKGROUND: Ozonated water (O3 wat) soil drench and/or foliar spray applications were evaluated for their potential to control the root-knot nematode Meloidogyne incognita (RKN) and the airborne pathogen Tomato spotted wilt virus (TSWV) in tomato. We investigated how O3 wat modulates the salicylic acid/jasmonic acid/ethylene (SA/JA/ET) signalling network in the host, locally and systemically, to induce resistance to nematode and virus. RESULTS: The application as soil drench was effective in reducing the number of galls and egg masses, but did not reduce the incidence and severity of TSWV infection. Conversely, O3 wat applied by foliar spray decreased TSWV disease incidence and severity (-20%), but was not able to control M. incognita infection. SA-related genes were generally upregulated in both locally treated and systemically reached tissues, showing a positive action of the O3 wat treatment on SA signalling. Neither O3 wat application method significantly altered JA-related gene expression in either direction. ET-related genes were differentially regulated by root or leaf treatments, indicating that O3 wat may have different effects on ET-mediated signalling in different organs. JA/ET/SA related pathways were differentially modulated by O3 wat in the presence of either RKN or TSWV. CONCLUSION: O3 wat had a higher efficacy when applied directly to organs challenged by the pathogens, although it was potentially able to stimulate defence responses through the activation of SA signalling. Owing to its safety and effectiveness in controlling nematode and virus infections, O3 wat can be considered as a possible alternative tool for sustainable disease management practices. © 2019 Society of Chemical Industry.


Assuntos
Lycopersicon esculentum/efeitos dos fármacos , Ozônio/administração & dosagem , Doenças das Plantas/prevenção & controle , Imunidade Vegetal , Tospovirus/fisiologia , Tylenchoidea/fisiologia , Animais , Lycopersicon esculentum/fisiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/virologia , Reguladores de Crescimento de Planta/fisiologia , Imunidade Vegetal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
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