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1.
Gene ; 727: 144245, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715302

RESUMO

DEK involves in the modulation of cell proliferation, differentiation, apoptosis, migration and cell senescence. However, direct genetic evidence proving the functions of DEK in disease resistance against pathogens is still deficient. In the present study, four DEKs were identified in tomato genome and their roles in disease resistance in tomato were analyzed. The expression levels of DEKs were differently induced by Botrytis cinerea, Pseudomonas syringae pv. tomato (Pst) DC3000 and defense-related signaling molecules (such as jasmonic acid, aethylene precursor and salicylic acid). The DEKs' silencing by virus induced gene silencing led to decreased resistance against B. cinerea or Pst DC3000. The underlying mechanisms may be through the upregulation of the accumulation of reactive oxygen species (ROS) and the changed expression levels of defense-related genes by pathogen inoculation. These results indicate that DEKs involve in disease resistance against different pathogens and thus broaden the knowledge of DEK genes' function in tomato.


Assuntos
Resistência à Doença/genética , Inativação Gênica/efeitos dos fármacos , Lycopersicon esculentum/genética , Botrytis/patogenicidade , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Lycopersicon esculentum/metabolismo , Oxilipinas/farmacologia , Doenças das Plantas/genética , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Pseudomonas syringae/patogenicidade , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Transdução de Sinais/genética , Fatores de Transcrição/genética
2.
Zhongguo Zhong Yao Za Zhi ; 44(18): 3954-3959, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31872730

RESUMO

Through investigation,it was found that the main disease of leaves was grey mold on Dendrobium officinale in Hubei province,which has a great impact on the yield and quality of D. officinale. The identification of morphological and molecular biological was used to prove that the pathogen was Botrytis cinerea. Through test the effect of 5 plant source fungicides and 4 antibiotic fungicides on mycelial growth of strain HS1,which proved 0. 3% eugenol had the best inhibitory effect,EC50 was 0. 29 mg·L-1,the second was1% osthol and EC50 was 1. 12 mg·L-1,the EC50 of 0. 5% matrine was 9. 16 mg·L-1,the EC50 of the other six fungicides was higher than 10 mg·L-1. The field control effect test proved that 0. 3% eugenol had the best control effect,reaching 89. 44%,secondly for 1%osthole,which was 77. 17%,0. 5% matrine was in the third place with 62. 37% of effective rate. However,the control effect of the other fungicides was less than 60%. The three plant-derived fungicides were safe for the produce of D. officinale and showed no phytotoxicity. The effect of these fungicides on the growth of D. candidum was tested,and proved that all the fungicides were safe and harmless to D. candidum. This study provides a research basis for the safe and effective prevention and control gray mold of D. officinale.


Assuntos
Botrytis/patogenicidade , Dendrobium/microbiologia , Fungicidas Industriais , Doenças das Plantas/microbiologia , Alcaloides , Botrytis/efeitos dos fármacos , Cumarínicos , Eugenol , Doenças das Plantas/prevenção & controle , Folhas de Planta/microbiologia , Quinolizinas
3.
Nat Commun ; 10(1): 4802, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641114

RESUMO

Microbes can establish mutualistic interactions with plants and insects. Here we track the movement of an endophytic strain of Streptomyces bacteria throughout a managed strawberry ecosystem. We show that a Streptomyces isolate found in the rhizosphere and on flowers protects both the plant and pollinating honeybees from pathogens (phytopathogenic fungus Botrytis cinerea and pathogenic bacteria, respectively). The pollinators can transfer the Streptomyces bacteria among flowers and plants, and Streptomyces can move into the plant vascular bundle from the flowers and from the rhizosphere. Our results present a tripartite mutualism between Streptomyces, plant and pollinator partners.


Assuntos
Abelhas/fisiologia , Fragaria/fisiologia , Streptomyces/fisiologia , Animais , Botrytis/patogenicidade , Flores , Fragaria/microbiologia , Doenças das Plantas/microbiologia , Pólen , Polinização , RNA Ribossômico 16S , República da Coreia , Esporos Fúngicos , Streptomyces/genética , Simbiose
4.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614458

RESUMO

Small RNAs function to regulate plant defense responses to pathogens. We previously showed that miR825 and miR825* downregulate Bacillus cereus AR156 (AR156)-triggered systemic resistance to Pseudomonassyringae pv. tomato DC3000 in Arabidopsis thaliana (Arabidopsis). Here, Northern blotting revealed that miR825 and miR825* were more strongly downregulated in wild type Arabidopsis Col-0 (Col-0) plants pretreated with AR156 than in nontreated plants upon Botrytis cinerea (B. cinerea) B1301 infection. Furthermore, compared with Col-0, transgenic plants with attenuated miR825 and miR825* expression were more resistant to B. cinerea B1301, yet miR825- and miR825*-overexpressing (OE) plants were more susceptible to the pathogen. With AR156 pretreatment, the transcription of four defense-related genes (PR1, PR2, PR5, and PDF1.2) and cellular defense responses (hydrogen peroxide production and callose deposition) were faster and stronger in miR825 and miR825* knockdown lines but weaker in their OE plants than in Col-0 plants upon pathogen attack. Also, AR156 pretreatment caused stronger phosphorylation of MPK3 and MPK6 and expression of FRK1 and WRKY53 genes upon B. cinerea B1301 inoculation in miR825 and miR825* knockdown plants than in Col-0 plants. Additionally, the assay of agrobacterium-mediated transient co-expression in Nicotiana benthamiana confirmed that AT5G40910, AT5G38850, AT3G04220, and AT5G44940 are target genes of miR825 or miR825*. Compared with Col-0, the target mutant lines showed higher susceptibility to B. cinerea B1301, while still expressing AR156-triggered induced systemic resistance (ISR). The two-way analysis of variance (ANOVA) revealed a significant (P < 0.01) interactive effect of treatment and genotype on the defense responses. Hence, miR825 and miR825*act as negative regulators of AR156-mediated systemic resistance to B. cinerea B1301 in Arabidopsis.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Bacillus cereus/fisiologia , Resistência à Doença , MicroRNAs/genética , Arabidopsis/genética , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Botrytis/patogenicidade , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes/efeitos dos fármacos , Imunidade Vegetal , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/microbiologia , RNA de Plantas/genética
5.
Plant Physiol Biochem ; 143: 329-339, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31539762

RESUMO

Grape (Vitis vinifera L.) is one of the most widely cultivated and economically important fruits. Most cultivated varieties of grape are highly susceptible to fungal diseases, and one of the most pervasive is powdery mildew, caused by Uncinula necator. The jasmonate-ZIM domain (JAZ) family proteins are critical for plant responses to environmental stresses. Here, we report the characterization of VqJAZ4, a jasmonate-ZIM domain gene isolated from Vitis quinquangularis, a Chinese wild Vitis species that exhibits high tolerance to several kinds of fungi. Subcellular localization assay indicated that the VqJAZ4 protein is targeted to the nucleus. The VqJAZ4 gene was strongly induced by U. necator inoculation, as well as by the defense-related hormones methyl jasmonate (MeJA) and salicylic acid (SA). The upregulation of VqJAZ4 after inoculation was dependent on its promoter sequences. Expression of VqJAZ4 in Arabidopsis thaliana improved resistance to powdery mildew. Histochemical staining assays indicated that plants expressing VqJAZ4 displayed a larger number of dead cells and stronger reactive oxygen species (ROS) burst than non-transgenic control (NTC) plants. Expression analysis of several disease-related genes suggested that VqJAZ4 expression enhanced defense responses though SA and/or JA signaling pathways. We also found that VqJAZ4-expressing Arabidopsis showed increased susceptibility to Botrytis cinerea. Taken together, these results provide evidence that VqJAZ4 may play an important role in response to fungal pathogens in grape, and may represent a candidate for future grape molecular breeding for disease resistance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Acetatos/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Botrytis/patogenicidade , Cruzamento , Ciclopentanos/farmacologia , Resistência à Doença/genética , Resistência à Doença/fisiologia , Oxilipinas/farmacologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia
6.
Phytopathology ; 109(10): 1679-1688, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31479404

RESUMO

Alternative oxidase (AOX) is a ubiquinol terminal oxidase that is involved in fungal mitochondrial oxidative phosphorylation. In this study, we analyzed the roles of AOX in Botrytis cinerea by generating BcAOX deletion mutants. The mutants exhibited defects in mycelial growth, sporulation, spore germination, and virulence. Furthermore, the sensitivity of the mutants to quinone outside inhibitor fungicides and oxidative stress were increased. All phenotypic variations could be restored in the complemented strain. In summary, these results showed that BcAOX is involved in the regulation for vegetative development, adaptation to environmental stress, and virulence of B. cinerea.


Assuntos
Botrytis , Proteínas Mitocondriais , Oxirredutases , Oxigênio , Proteínas de Plantas , Botrytis/enzimologia , Botrytis/crescimento & desenvolvimento , Botrytis/patogenicidade , Proteínas Mitocondriais/metabolismo , Estresse Oxidativo/fisiologia , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Virulência
7.
BMC Infect Dis ; 19(1): 684, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375066

RESUMO

BACKGROUND: Botrytis species are well known fungal pathogens of various plants but have not been reported as human pathogens, except as allergenic precipitants of asthma and hypersensitivity pneumonitis. CASE PRESENTATION: The asymptomatic patient was referred because of a nodule revealed by chest X-ray. Computed tomography (CT) showed a cavitary nodule in the right upper lobe of the lung. He underwent wedge resection of the nodule, which revealed necrotizing granulomas and a fungus ball containing Y-shaped filamentous fungi, which was confirmed histopathologically. Culture of the specimen yielded white to grayish cotton-like colonies with black sclerotia. We performed multilocus gene sequence analyses including three single-copy nuclear DNA genes encoding glyceraldehyde-3-phosphate dehydrogenase, heat-shock protein 60, and DNA-dependent RNA polymerase subunit II. The analyses revealed that the isolate was most similar to Botrytis elliptica. To date, the pulmonary Botrytis sp. infection has not recurred after lung resection and the patient did not require any additional medication. CONCLUSIONS: We report the first case of an immunocompetent patient with pulmonary Botrytis sp. infection, which has not recurred after lung resection without any additional medication. Precise evaluation is necessary for the diagnosis of pulmonary Botrytis infection because it is indistinguishable from other filamentous fungi both radiologically and by histopathology. The etiology and pathophysiology of pulmonary Botrytis infection remains unclear. Further accumulation and analysis of Botrytis cases is warranted.


Assuntos
Botrytis/patogenicidade , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/microbiologia , Biópsia , Botrytis/genética , Proteínas Fúngicas/genética , Humanos , Pneumopatias Fúngicas/patologia , Pneumopatias Fúngicas/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
8.
Molecules ; 24(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319619

RESUMO

In order to explore more efficient sulfonamides against Botrytis cinereal, 36 novel cyclohexylsulfonamides were synthesized by N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDCI) and 1-hydroxybenzotriazole (HOBt) condensation reaction using chesulfamide as a lead compound, introducing thiazole and pyrazole active groups. Their structures were characterized by 1H-NMR, 13C-NMR, mass spectrum (MS), and elemental analysis. Compound III -31 was further confirmed by X-ray single crystal diffraction. The in vitro and in vivo fungicidal activities against B. cinerea were evaluated by three bioassay methods. The results of mycelial growth demonstrated that median effective concentration (EC50) values of nine compounds were close to boscalid (EC50 = 1.72 µg/mL) and procymidone (EC50 = 1.79 µg/mL) against B. cinerea (KZ-9). In the spore germination experiment, it was found that compounds III-19 and III-31 inhibited germination 93.89 and 98.00%, respectively; at 10 µg/mL, they approached boscalid (95.97%). In the tomato pot experiment, the control effects of two compounds (III-21 and III-27) were 89.80 and 87.90%, respectively, at 200 µg/mL which were significantly higher than boscalid (81.99%). The structure-activity relationship (SAR) was also discussed, which provided a valuable idea for developing new fungicides.


Assuntos
Botrytis/efeitos dos fármacos , Fungicidas Industriais/química , Sulfonamidas/química , Botrytis/patogenicidade , Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Tiazóis/síntese química , Tiazóis/química
9.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315176

RESUMO

In this study we cloned a chitinase gene (SmchiC), from Serratia marcescens isolated from the corpse of a Diatraea magnifactella lepidopteran, which is an important sugarcane pest. The chitinase gene SmchiC amplified from the S. marcescens genome was cloned into the transformation vector p2X35SChiC and used to transform tobacco (Nicotiana tabacum L. cv Petit Havana SR1). The resistance of these transgenic plants to the necrotrophic fungus Botrytis cinerea and to the pest Spodoptera frugiperda was evaluated: both the activity of chitinase as well as the resistance against B. cinerea and S. frugiperda was significantly higher in transgenic plants compared to the wild-type.


Assuntos
Proteínas de Bactérias/genética , Quitinases/genética , Resistência à Doença/genética , Serratia marcescens/genética , Tabaco/genética , Transgenes , Animais , Proteínas de Bactérias/metabolismo , Botrytis/patogenicidade , Quitinases/metabolismo , Spodoptera/patogenicidade , Tabaco/microbiologia , Tabaco/parasitologia
10.
Plant Mol Biol ; 100(6): 659-674, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187392

RESUMO

KEY MESSAGE: Oxalotrophic Stenotrophomonas isolated from tomato rhizosphere are able to protect plants against oxalate-producing pathogens by a combination of actions including induction of plant defence signalling callose deposition and the strengthening of plant cell walls and probably the degradation of oxalic acid. Oxalic acid plays a pivotal role in the virulence of the necrotrophic fungi Botrytis cinerea and Sclerotinia sclerotiorum. In this work, we isolated two oxalotrophic strains (OxA and OxB) belonging to the bacterial genus Stenotrophomonas from the rhizosphere of tomato plants. Both strains were capable to colonise endophytically Arabidopsis plants and protect them from the damage caused by high doses of oxalic acid. Furthermore, OxA and OxB protected Arabidopsis from S. sclerotiorum and B. cinerea infections. Bacterial inoculation induced the production of phenolic compounds and the expression of PR-1. Besides, both isolates exerted a protective effect against fungal pathogens in Arabidopsis mutants affected in the synthesis pathway of salicylic acid (sid2-2) and jasmonate perception (coi1). Callose deposition induced by OxA and OxB was required for protection against phytopathogens. Moreover, B. cinerea and S. sclerotiorum mycelial growth was reduced in culture media containing cell wall polysaccharides from leaves inoculated with each bacterial strain. These findings suggest that cell walls from Arabidopsis leaves colonised by these bacteria would be less susceptible to pathogen attack. Our results indicate that these oxalotrophic bacteria can protect plants against oxalate-producing pathogens by a combination of actions and show their potential for use as biological control agents against fungal diseases.


Assuntos
Fungos/patogenicidade , Lycopersicon esculentum/microbiologia , Oxalatos/metabolismo , Stenotrophomonas/fisiologia , Arabidopsis/metabolismo , Botrytis/metabolismo , Botrytis/patogenicidade , Parede Celular/metabolismo , Ciclopentanos/química , Fungos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácido Oxálico/metabolismo , Oxilipinas/química , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Polissacarídeos/metabolismo , Ácido Salicílico/farmacologia , Transdução de Sinais , Stenotrophomonas/isolamento & purificação
11.
Elife ; 82019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31081752

RESUMO

A central goal of studying host-pathogen interaction is to understand how host and pathogen manipulate each other to promote their own fitness in a pathosystem. Co-transcriptomic approaches can simultaneously analyze dual transcriptomes during infection and provide a systematic map of the cross-kingdom communication between two species. Here we used the Arabidopsis-B. cinerea pathosystem to test how plant host and fungal pathogen interact at the transcriptomic level. We assessed the impact of genetic diversity in pathogen and host by utilization of a collection of 96 isolates infection on Arabidopsis wild-type and two mutants with jasmonate or salicylic acid compromised immunities. We identified ten B. cinereagene co-expression networks (GCNs) that encode known or novel virulence mechanisms. Construction of a dual interaction network by combining four host- and ten pathogen-GCNs revealed potential connections between the fungal and plant GCNs. These co-transcriptome data shed lights on the potential mechanisms underlying host-pathogen interaction.


Assuntos
Arabidopsis/microbiologia , Botrytis/genética , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Transcriptoma/genética , Proteínas de Arabidopsis/genética , Botrytis/patogenicidade , Ciclopentanos/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Oxilipinas/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Ácido Salicílico/metabolismo
12.
BMC Genomics ; 20(1): 385, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101009

RESUMO

BACKGROUND: Narrow-leafed lupin is an emerging crop of significance in agriculture, livestock feed and human health food. However, its susceptibility to various diseases is a major obstacle towards increased adoption. Sclerotinia sclerotiorum and Botrytis cinerea - both necrotrophs with broad host-ranges - are reported among the top 10 lupin pathogens. Whole-genome sequencing and comparative genomics are useful tools to discover genes responsible for interactions between pathogens and their hosts. RESULTS: Genomes were assembled for one isolate of B. cinerea and two isolates of S. sclerotiorum, which were isolated from either narrow-leafed or pearl lupin species. Comparative genomics analysis between lupin-derived isolates and others isolated from alternate hosts was used to predict between 94 to 98 effector gene candidates from among their respective non-conserved gene contents. CONCLUSIONS: Detection of minor differences between relatively recently-diverged isolates, originating from distinct regions and with hosts, may highlight novel or recent gene mutations and losses resulting from host adaptation in broad host-range fungal pathogens.


Assuntos
Adaptação Fisiológica , Ascomicetos/genética , Botrytis/genética , Proteínas Fúngicas/genética , Genoma Fúngico , Lupinus/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/patogenicidade , Botrytis/patogenicidade , Especificidade de Hospedeiro , Virulência , Sequenciamento Completo do Genoma
13.
PLoS One ; 14(4): e0214811, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30946768

RESUMO

Plastids perform many essential functions in plant metabolism including photosynthesis, synthesis of metabolites, and stress signaling. The most prominent type in green leaves is the chloroplast which contains thylakoids, plastoglobules, and starch. As these structures are closely linked to the metabolism of chloroplasts, changes during plant growth and development and during environmental stress situations are likely to occur. The aim of this study was to characterize changes in size and ultrastructure of chloroplast on cross-sections of leaves during high light stress, Botrytis infection, and dark induced senescence by quantitative transmission electron microscopy (TEM).The size of chloroplasts on cross sections of leaves decreased significantly when plants were subject to high light (49%), Botrytis infection (58%), and senescence (71%). The number of chloroplasts on cross sections of the palisade cell layer and spongy parenchyma, respectively, decreased significantly in plants exposed to high light conditions (48% and 29%), infected with Botrytis (48% and 46%), and during senescence (78% and 80%). Thylakoids on cross-sections of chloroplasts decreased significantly in plants exposed to high light (22%), inoculated with Botrytis cinerea (36%), and senescence (51%). This correlated with a massive increase in plastoglobules on cross-sections of chloroplasts of 88%, 2,306% and 19,617%, respectively. Starch contents on cross sections of chloroplasts were completely diminished in all three stress scenarios. These results demonstrate that the decrease in the number and size of chloroplasts is a reliable stress marker in plants during abiotic and biotic stress situations which can be easily detected with a light microscope. Further, lack of starch, the occurrence of large plastoglobules and decrease in thylakoids can also be regarded as reliable stress marker in plants which can be detected by TEM.


Assuntos
Plastídeos/ultraestrutura , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Arabidopsis/ultraestrutura , Botrytis/patogenicidade , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Luz , Microscopia Eletrônica de Transmissão , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Plastídeos/metabolismo , Amido/metabolismo , Estresse Fisiológico , Tilacoides/metabolismo , Tilacoides/ultraestrutura
14.
Phytopathology ; 109(8): 1367-1377, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30990377

RESUMO

Polyamines (PAs) are ubiquitous aliphatic amines that play important roles in growth, development, and environmental stress responses in plants. In this study, we report that exogenous application of spermine (Spm) is effective in the induction of resistance to gray mold disease, which is caused by the necrotrophic fungal pathogen Botrytis cinerea, on tomato (Solanum lycopersicum), bean (Phaseolus vulgaris), and Arabidopsis thaliana. High throughput transcriptome analysis revealed a priming role for the Spm molecule in the genus Arabidopsis, resulting in strong upregulation of several important defense-associated genes, particularly those involved in systemic-acquired resistance. Microscopic analysis confirmed that Spm application potentiates endogenous defense responses in tomato leaves through the generation of reactive oxygen species and the hypersensitive response, which effectively contained B. cinerea growth within the inoculated area. Moreover, co-application of Spm and salicylic acid resulted in a synergistic effect against the pathogen, leading to higher levels of resistance than those induced by separate applications of the two compounds. The Spm plus salicylic acid treatment also reduced infection in systemic nontreated leaves of tomato plants. Our findings suggest that Spm, particularly when applied in combination with salicylic acid, functions as a potent plant defense activator that leads to effective local and systemic resistance against B. cinerea.


Assuntos
Arabidopsis , Botrytis/patogenicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lycopersicon esculentum , Phaseolus , Espermina/farmacologia , Resistência à Doença , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Ácido Salicílico/metabolismo
15.
Int J Mol Sci ; 20(5)2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30823420

RESUMO

The concept of "Sweet Immunity" postulates that sugar metabolism and signaling influence plant immune networks. In this study, we tested the potential of commercially available inulin-type fructans to limit disease symptoms caused by Botrytis cinerea in lettuce. Spraying mature lettuce leaves, with inulin-type fructans derived from burdock or chicory was as effective in reducing grey mold disease symptoms caused by Botrytis cinerea as spraying with oligogalacturonides (OGs). OGs are well-known defense elicitors in several plant species. Spraying with inulin and OGs induced accumulation of hydrogen peroxide and levels further increased upon pathogen infection. Inulin and OGs were no longer able to limit Botrytis infection when plants were treated with the ethylene signaling inhibitor 1-methylcyclopropene (1-MCP), indicating that a functional ethylene signaling pathway is needed for the enhanced defense response. Soluble sugars accumulated in leaves primed with OGs, while 1-MCP treatment had an overall negative effect on the sucrose pool. Accumulation of γ-aminobutyric acid (GABA), a stress-associated non-proteinogenic amino acid and possible signaling compound, was observed in inulin-treated samples after infection and negatively affected by the 1-MCP treatment. We have demonstrated for the first time that commercially available inulin-type fructans and OGs can improve the defensive capacity of lettuce, an economically important species. We discuss our results in the context of a possible recognition of fructans as Damage or Microbe Associated Molecular Patterns.


Assuntos
Botrytis/patogenicidade , Inulina/farmacologia , Alface/imunologia , Imunidade Vegetal , Ciclopropanos/farmacologia , Etilenos/metabolismo , Peróxido de Hidrogênio/metabolismo , Alface/efeitos dos fármacos , Alface/microbiologia , Ácido gama-Aminobutírico/metabolismo
16.
Food Chem ; 286: 226-233, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827600

RESUMO

Gray mold caused by Botrytis cinerea is a major postharvest disease of table grapes that leads to enormous economic losses during storage and transportation. The objective of this study was to evaluate the effectiveness of fulvic acid on controlling gray mold of table grapes and explore its mechanism of action. The results showed that fulvic acid application significantly reduced downy blight severity in table grapes without exhibiting any antifungal activity in vitro. Fulvic acid induced phenylpropanoid metabolism, as evidenced by accumulation of phenolic compounds and flavonoids, higher activities of phenylalanine ammonia-lyase (PAL), cinnamate-4-hydroxylase (C4H) and 4-coumarate-CoA ligase (4CL), up-regulation of genes related to phenylpropanoid biosynthesis (PAL, C4H, 4CL, STS, ROMT and CHS). Our results suggested that fulvic acid induces resistance to B. cinerea mainly through the activation of phenylpropanoid pathway and can be used as a new activator of plant defense responses to control postharvest gray mold in table grapes.


Assuntos
Benzopiranos/farmacologia , Botrytis/patogenicidade , Frutas/microbiologia , Vitis/metabolismo , Vitis/microbiologia , Botrytis/efeitos dos fármacos , Coenzima A Ligases/metabolismo , Resistência à Doença , Flavonoides/metabolismo , Microbiologia de Alimentos , Frutas/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fenilalanina Amônia-Liase/metabolismo , Fenilpropionatos/metabolismo , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Transcinamato 4-Mono-Oxigenase/metabolismo , Vitis/efeitos dos fármacos
17.
World J Microbiol Biotechnol ; 35(3): 40, 2019 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-30739227

RESUMO

Grey mould caused by Botrytis cinerea is among the most important disease affecting the production of grapevine worldwide. The high economical loss each year has led producers to become more dependent on chemical pesticides for protection. However, environmental impacts of the pesticides overuse have sparked crescent interest in developing alternative biocontrol methods. The use of plant-associated bacteria has, thus, received many attentions as a promising strategy for sustainable agriculture. Three strains, isolated from the rhizosphere of crops cultivated in the northeast of France, were evaluated for their antagonistic effect. They were found to exhibit an antagonistic effect against a set of phytopathogenic fungi. Phenotypic and molecular characterization showed that isolates belong to the genus Burkholderia. The genome sequencing and analysis of isolated strains revealed the presence of gene clusters coding for secondary metabolites potentially involved in the biocontrol. When the grapevine plantlets were infected with B. cinerea, all plants associated with isolated strains showed a significant protection against B. cinerea compared to non-inoculated plants. To understand the mechanisms contributing to the biocontrol effect of selected isolates, the production of reactive oxygen species (ROS) and the expression of several defense genes were investigated. The maximum accumulation of H2O2 was detected in the inoculated cell suspension medium 30 min after the challenge with B. cinerea. After pathogen challenge, results showed that grapevine cell culture inoculated with isolated strains exhibited significant over expression of defense markers genes PR5, PR10, and chit4c, in response to B. cinerea, confirming their priming effect.


Assuntos
Antibiose/genética , Agentes de Controle Biológico/farmacologia , Botrytis/efeitos dos fármacos , Burkholderia/genética , Burkholderia/metabolismo , Doenças das Plantas/prevenção & controle , Vitis/microbiologia , Antibiose/fisiologia , Agentes de Controle Biológico/isolamento & purificação , Botrytis/crescimento & desenvolvimento , Botrytis/patogenicidade , Burkholderia/classificação , Burkholderia/isolamento & purificação , Produtos Agrícolas/microbiologia , França , Regulação Bacteriana da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes Bacterianos/genética , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Família Multigênica , Fosfatos/metabolismo , Filogenia , Doenças das Plantas/microbiologia , RNA Ribossômico 16S/genética , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Rizosfera , Metabolismo Secundário/genética , Sideróforos/metabolismo , Microbiologia do Solo , Vitis/genética , Vitis/metabolismo , Sequenciamento Completo do Genoma
18.
Plant Cell ; 31(2): 502-519, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30647076

RESUMO

Although the impacts of crop domestication on specialist pathogens are well known, less is known about the interaction of crop variation and generalist pathogens. To study how genetic variation within a crop affects plant resistance to generalist pathogens, we infected a collection of wild and domesticated tomato accessions with a genetically diverse population of the generalist pathogen Botrytis cinerea We quantified variation in lesion size of 97 B. cinerea genotypes (isolates) on six domesticated tomato genotypes (Solanum lycopersicum) and six wild tomato genotypes (Solanum pimpinellifolium). Lesion size was significantly affected by large effects of the host and pathogen's genotype, with a much smaller contribution of domestication. This pathogen collection also enables genome-wide association mapping of B. cinerea Genome-wide association mapping of the pathogen showed that virulence is highly polygenic and involves a diversity of mechanisms. Breeding against this pathogen would likely require the use of diverse isolates to capture all possible mechanisms. Critically, we identified a subset of B. cinerea genes where allelic variation was linked to altered virulence against wild versus domesticated tomato, as well as loci that could handle both groups. This generalist pathogen already has a large collection of allelic variation that must be considered when designing a breeding program.


Assuntos
Botrytis/patogenicidade , Lycopersicon esculentum/genética , Alelos , Estudo de Associação Genômica Ampla , Genótipo , Lycopersicon esculentum/metabolismo , Virulência
19.
Curr Genet ; 65(1): 293-300, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30167777

RESUMO

Autophagy serves as a survival mechanism against starvation and has been reported to be important for cell growth and differentiation in eukaryotes. Here, we investigated the function of a cysteine protease BcAtg4 in the gray mold fungus Botrytis cinerea. Yeast complementation experiments revealed that Bcatg4 can functionally replace the counterpart of yeast. Subcellular localization exhibited that BcAtg4 diffused in cytoplasm at different developmental stages. Targeted gene deletion of Bcatg4 (ΔBcatg4) led to autophagy blocking and a significant retardation in growth and conidiation. In addition, ΔBcatg4 failed to form sclerotia. Infection tests demonstrated that ΔBcatg4 was severely attenuated in virulence on different host plant tissues. All of the phenotypic defects were restored by reintroducing an intact copy of Bcatg4 into ΔBcatg4. These results indicate that Bcatg4 plays multiple roles in the developmental processes and pathogenesis of B. cinerea.


Assuntos
Botrytis/genética , Cisteína Proteases/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Sequência de Aminoácidos , Autofagia/genética , Botrytis/metabolismo , Botrytis/patogenicidade , Cucumis sativus/microbiologia , Cisteína Proteases/classificação , Cisteína Proteases/metabolismo , Proteínas Fúngicas/classificação , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Mutação , Filogenia , Folhas de Planta/microbiologia , Homologia de Sequência de Aminoácidos , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Virulência/genética
20.
Fungal Genet Biol ; 123: 14-24, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30445217

RESUMO

The Leotiomycete Botrytis cinerea is a high-impact plant pathogen causing gray mold disease in a wide range of dicotyledonous species. Besides its efficient strategies to cause disease - either by being highly aggressive leading to rapid destruction of plant tissues or by keeping hidden for certain periods before damaging the host - the fungus is well-adapted to the changing environmental conditions due to different modes of reproduction for dispersal (macroconidia), survival (sclerotia) or adaptation (ascospores formed in the apothecia). The screening of a collection of B. cinerea mutants generated by Agrobacterium tumefaciens-mediated transformation (ATMT) has revealed a number of virulence-attenuated mutants. In the avirulent mutant PA2810 the inserted T-DNA disrupts the gene encoding a putative histone 3 lysine 36 (H3K36)-specific demethylase (BcKDM1). Targeted mutagenesis of bckdm1 confirmed the gene-phenotype linkage and indicated that BcKDM1, despite its role in virulence (critical for penetration), is required for coping with excessive light, oxidative stress and for proper expression of light-responsive genes and photomorphogenesis. Thus, bckdm1 loss-of-function mutants produce sclerotia under unfavorable conditions such as in the light. Notably, mutants expressing a truncated BcKDM1 (bckdm1991aa) showed deviating phenotypes from deletion (Δbckdm1) and demethylase-deficient (bckdm1H360A) mutants but also from the wild type, thereby indicating the importance of the C-terminal region for some developmental processes. This effect may be specific to B. cinerea as the orthologs from other Ascomycetes cannot replace BcKDM1.


Assuntos
Botrytis/genética , Histona Desmetilases/genética , Doenças das Plantas/genética , Estresse Fisiológico/genética , Botrytis/crescimento & desenvolvimento , Botrytis/patogenicidade , Regulação Fúngica da Expressão Gênica , Morfogênese/genética , Doenças das Plantas/microbiologia , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Virulência/genética
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