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1.
J Agric Food Chem ; 67(33): 9265-9276, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361479

RESUMO

Fungal infections significantly alter the emissions of volatile organic compounds (VOCs) by plants, but the mechanisms for VOCs affecting fungal infections of plants remain largely unknown. Here, we found that infection by Botrytis cinerea upregulated linalool production by strawberries and fumigation with linalool was able to inhibit the infection of fruits by the fungus. Linalool treatment downregulated the expression of rate-limiting enzymes in the ergosterol biosynthesis pathway, and this reduced the ergosterol content in the fungi cell membrane and impaired membrane integrity. Linalool treatment also caused damage to mitochondrial membranes by collapsing mitochondrial membrane potential and also downregulated genes involved in adenosine triphosphate (ATP) production, resulting in a significant decrease in the ATP content. Linalool treatment increased the levels of reactive oxygen species (ROS), in response to which the treated fungal cells produced more of the ROS scavenger pyruvate. RNA-Seq and proteomic analysis data showed that linalool treatment slowed the rates of transcription and translation.


Assuntos
Botrytis/efeitos dos fármacos , Fragaria/metabolismo , Frutas/microbiologia , Monoterpenos/metabolismo , Doenças das Plantas/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Trifosfato de Adenosina/metabolismo , Botrytis/crescimento & desenvolvimento , Fragaria/química , Fragaria/microbiologia , Frutas/química , Frutas/metabolismo , Interações Hospedeiro-Patógeno , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Monoterpenos/farmacologia , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Compostos Orgânicos Voláteis/farmacologia
2.
Plant Dis ; 103(6): 1213-1219, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30964418

RESUMO

To provide a high-throughput, efficient, and accurate method to monitor multiple-fungicide resistance of Botrytis cinerea in the field, we used the suspension array, sequencing, and mycelial growth assay in our research. Discriminating-dose bioassays for detecting carbendazim, diethofencarb, boscalid, and iprodione resistance (CarR, DieR, BosR, and IprR, respectively) were used to analyze 257 isolates collected from Hebei Province in China during 2016 and 2017. High resistance frequencies to carbendazim (100%), diethofencarb (92.08%), and iprodione (86.59%) were detected. BosR isolates accounted for 11.67% of the total. In addition, 103 isolates were randomly selected for phenotype and genotype detection. The high-throughput suspension array was utilized to detect eight genotypes simultaneously, including BenA-E198, BenA-198A, SdhB-H272, SdhB-272Y, BcOS1-I365, BcOS1-365S, erg27-F412, and erg27-412S, which were associated with resistance toward carbendazim or diethofencarb, boscalid, iprodione, and fenhexamid (FenR), respectively. Most of the benzimidazole-resistant isolates (81.55%) possessed the E198V mutation in the BenA gene. Ninety-three isolates with dual resistance to carbendazim and diethofencarb showed the E198V/K mutation. All BosR isolates carried the H272R mutation in the SdhB gene. The I365S and Q369P+N373S (66.99%) mutations in the BcOS1 gene were more frequently observed. No mutation was detected in the erg27 gene in Hebei isolates. There were 13 resistance profile phenotypes. Phenotypes with triple resistance were the most common (83.50%), and CarRDieRBosSIprRFenS was the major type. CarR isolates that carried E198V/K/A were all highly resistant (HR) and only one F200Y mutant was moderately resistant (MR) to carbendazim. Isolates that possessed E198V/K were MR or HR to diethofencarb. BosR isolates that possessed H272R mutation were lowly resistant (LR). IprR isolates were all LR or MR. The distribution of half maximal effective concentrations of CarR isolates with E198V/K mutations and IprR isolates with Q369P+N373S mutations significantly increased from 2016 to 2017. Combined with our observations, a combination method of the high-throughput suspension array and the mycelial growth assay was suggested to accurately monitor multiple resistance of B. cinerea in the field.


Assuntos
Botrytis , Farmacorresistência Fúngica , Fungicidas Industriais , Bioensaio , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , China , Farmacorresistência Fúngica/genética , Fungicidas Industriais/farmacologia , Genes Fúngicos/genética
3.
J Appl Microbiol ; 127(1): 175-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30980449

RESUMO

AIMS: This study aimed to compare the effects of cold plasma (CP), ultraviolet (UV-C) and aqueous ozone (AO) on Botrytis cinerea and explore their application in preserving blueberry. METHODS AND RESULTS: The effects of CP, UV-C or AO on B. cinerea were investigated. Results showed that three treatments effectively inhibited the growth of B. cinerea, increasing cell membrane penetrability and causing the leakage of cytoplasm and nucleic acid. Scanning electron microscopy showed that CP caused the mycelium fold and collapse depression; UV-C caused the mycelium shrivelled; mycelium treated with AO appeared to fold and break. In the in vivo test in blueberry, all treatments effectively inhibited the growth of micro-organisms, maintained qualities and enhanced antioxidant activities in blueberry during postharvest storage. CONCLUSION: Cold plasma, UV-C and AO effectively inhibited the growth of B. cinerea and significantly extended the shelf life of blueberry. Based on in vitro and in vivo tests, CP showed better effects to preserve blueberry compared with other treatments. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings revealed the effective mechanisms of CP, UV-C and AO to inhibit B. cinerea in vitro. CP exhibited better application potential to preserve fresh fruit than traditional sterilization methods such as UV-C and AO.


Assuntos
Mirtilos Azuis (Planta) , Botrytis/efeitos dos fármacos , Botrytis/efeitos da radiação , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Frutas/microbiologia , Raios Ultravioleta , Botrytis/crescimento & desenvolvimento , Botrytis/metabolismo , Qualidade dos Alimentos , Frutas/fisiologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/efeitos da radiação , Ozônio/farmacologia , Gases em Plasma/farmacologia
4.
J Agric Food Chem ; 67(19): 5512-5520, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31008600

RESUMO

Crude extracts of Vitis vinifera canes represent a natural source of stilbene compounds with well characterized antifungals properties. In our trials, exogenous application of a stilbene extract (SE) obtained from grape canes on grapevine leaves reduces the necrotic lesions caused by Botrytis cinerea. The SE showed to possess a direct antifungal activity by inhibiting the mycelium growth. The activation of some grapevine defense mechanism was also investigated. H2O2 production and activation of mitogen-activated protein kinase (MAPK) phosphorylation cascades as well as accumulation of stilbenoid phytoalexins were explored on grapevine cell suspension. Moreover, the transcription of genes encoding for proteins affecting defense responses was analyzed on grapevine plants. The SE induced some grapevine defense mechanisms including MAPK activation, and the expression of pathogenesis-related (PR) genes and of a gene encoding the glutathione-S-transferase 1 ( GST1) . By contrast, treatment of grapevine leaves with SE negatively regulates de novo stilbene production.


Assuntos
Botrytis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Extratos Vegetais/farmacologia , Caules de Planta/química , Vitis/química , Vitis/microbiologia , Botrytis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estilbenos/farmacologia
5.
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
6.
Viruses ; 11(1)2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30609795

RESUMO

A pink isolate (QT5-19) of Botrytis cinerea was compared with three gray isolates of B. cinerea for growth and morphogenesis on potato dextrose agar (PDA), and for pathogenicity on tobacco. A double-stranded (ds) RNA mycovirus infecting QT5-19 was identified based on its genome feature and morphology of the virus particles. The results showed that QT5-19 grew rapidly and established flourishing colonies as the gray isolates did. However, it is different from the gray isolates, as it failed to produce conidia and sclerotia asthe gray isolates did. QT5-19 hardly infected tobacco, whereas the gray isolates aggressively infected tobacco. Two dsRNAs were detected in QT5-19, dsRNA 1 and dsRNA 2, were deduced to encode two polypepetides with homology to viral RNA-dependent RNA polymerase (RdRp) and coat protein (CP), respectively. Phylogenetic analysis of the amino acid sequences of RdRp and CP indicated that the two dsRNAs represent the genome of a novel partitivirus in the genus Alphapartitivirus, designated here as Botrytis cinerea partitivirus 2 (BcPV2). BcPV2 in QT5-19 was successfully transmitted to the three gray isolates through hyphal contact. The resulting BcPV2-infected derivatives showed rapid growth on PDA with defects in conidiogenesis and sclerogenesis, and hypovirulence on tobacco. This study suggests that BcPV2 is closely associated with hypovirulence of B. cinerea.


Assuntos
Botrytis/virologia , Micovírus/classificação , Genoma Viral , Botrytis/crescimento & desenvolvimento , Proteínas do Capsídeo/genética , Micovírus/isolamento & purificação , Filogenia , Pigmentação , Doenças das Plantas/microbiologia , RNA Replicase/genética , RNA de Cadeia Dupla , RNA Viral , Análise de Sequência de DNA , Esporos Fúngicos/crescimento & desenvolvimento , Tabaco/microbiologia
7.
Appl Microbiol Biotechnol ; 103(4): 1589-1597, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30610288

RESUMO

Grey mould, the most important disease of strawberry worldwide, is caused by Botrytis cinerea and a few additional Botrytis spp. Fungicide resistance is a growing problem and has become a limiting factor in strawberry production. In northern Germany, an annual survey of Botrytis isolates from commercial strawberry fields in 2010 to 2017 has revealed high (> 20%) frequencies of resistance to quinone-outside inhibitors, fenhexamid, boscalid, fludioxonil and cyprodinil, as well as lower (< 10%) shares of resistance to the recently released fluopyram. Iprodione and benzimidazoles have not been used in northern Germany for several years or decades, respectively, yet resistance to them was still detected. These observations are largely representative of the situation in many other strawberry-producing regions worldwide. The spread of strains with multiple resistance to several or even all currently used single-site fungicides is of particular concern and is probably promoted by their excessive use. Contaminated nursery material is a newly detected potential vehicle for the spread of strains with (multiple) fungicide resistance. Several complementary non-chemical measures are available to secure strawberry production in the face of weakening fungicide efficacies, and these are briefly discussed.


Assuntos
Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Farmacorresistência Fúngica , Fragaria/microbiologia , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Agricultura/métodos , Alemanha
8.
J Agric Food Chem ; 67(5): 1360-1370, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30640452

RESUMO

Oxathiapiprolin is one of the best active fungicides discovered for oomycetes control. To develop a fungicide candidate with a broad spectrum of activity, 22 new piperidinylthiazole derivatives were designed and synthesized. Compound 5l showed the best activity against Pseudoperonospora cubensis (Berk. et Curt.) Rostov and Phytophthora infestans in vivo with 100% and 80% of inhibition, respectively, at 1 mg/L, and 72.87% of field efficacy against P. cubensis at 1 g ai/667 m2 validated these results. Compound 5i exhibited a broad spectrum of excellent activity against Sclerotinia sclerotiorum with EC50 = 0.30 mg/L (>10 times more active than oxathiapiprolin and azoxystrobin in vitro), good activity against Botrytis cinerea, Cercospora arachidicola, and Gibberella zeae with EC50 of 14.54, 5.57, and 14.03 mg/L in vitro and against P. cubensis and P. infestans with 60% and 30% inhibition rates, respectively, at 1 mg/L in vivo. Mode of action studies by RNA sequencing analysis discovered oxysterol-binding protein (OSBP), chitin synthase (CHS1), and (1,3)-ß-glucan synthase (FKS2) as the potent target of 5i against S. sclerotiorum. Quenching studies validated that OSBP was the same target of both 5i and oxathiapiprolin; it was quenched by both of them. Our studies discovered isothiazole-containing piperidinylthiazole as an OSBP target-based novel lead for fungicide development.


Assuntos
Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Tiazóis/química , Tiazóis/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Cucumis sativus/microbiologia , Descoberta de Drogas , Lycopersicon esculentum/microbiologia , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Relação Estrutura-Atividade
9.
Food Microbiol ; 76: 450-456, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166173

RESUMO

The effect of temperature on the mycelium growth kinetics of four postharvest fungal isolates (i.e., Penicillium expansum, Alternaria alternata, Botrytis cinerea and Rhizopus stolonifer) was assessed. A cardinal model with inflection (CMI) was used to describe the effect of the temperature on the growth rate (µ) and the lag time (λ) of each isolate. Cardinal temperature values such as Tmin, Tmax and Topt were estimated and isolates were sorted according to their growth rate and lag time duration. Additionally, model validation was performed on a medium prepared from mashed pear pulp and on artificially wound-inoculated pear fruits. P. expansum was shown to be the most psychotrophic fungus with the lowest estimated Tmin = -8.78. Model validation on pear pulp agar showed growth rate over-prediction in the case of R. stolonifer and B. cinerea but a good correlation in the case of P. expansum and A. alternata. In vivo experiments on pear fruits showed discrepancies from the synthetic and the simulated counterparts for all the fungi with the only exception of P. expansum.


Assuntos
Alternaria/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Frutas/microbiologia , Penicillium/crescimento & desenvolvimento , Pyrus/microbiologia , Rhizopus/crescimento & desenvolvimento , Alternaria/química , Botrytis/química , Cinética , Penicillium/química , Rhizopus/química , Temperatura Ambiente
10.
Microbiol Res ; 215: 55-64, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30172309

RESUMO

Fusarium graminearum is the major causal agent of Fusarium head blight (FHB) disease in cereal crops worldwide. Infection with this fungal phytopathogen can regularly cause severe yield and quality losses and mycotoxin contamination in grains. In previous other studies, one research group reported that pyrrolnitrin had an ability to suppress of mycelial growth of F. graminearum. Other groups revealed that phenazine-1-carboxamide, a derivative of phenazine-1-carboxylic acid, could also inhibit the growth of F. graminearum and showed great potentials in the bioprotection of crops from FHB disease. In our recent work with Pseudomonas chlororaphis strain G05, however, we found that although the phz operon (phenazine biosynthetic gene cluster) was knocked out, the phenazine-deficient mutant G05Δphz still exhibited effective inhibition of the mycelial growth of some fungal phytopathogens in pathogen inhibition assay, especially including F. graminearum, Colletotrichum gloeosporioides, Botrytis cinerea. With our further investigations, including deletion and complementation of the prn operon (pyrrolnitrin biosynthetic gene cluster), purification and identification of fungal compounds, we first verified that not phenazines but pyrrolnitrin biosynthesized in P. chlororaphis G05 plays an essential role in growth suppression of F. graminearum and the bioprotection of cereal crops against FHB disease.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Fenazinas/antagonistas & inibidores , Fenazinas/metabolismo , Pseudomonas chlororaphis/metabolismo , Pirrolnitrina/antagonistas & inibidores , Pirrolnitrina/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Colletotrichum/efeitos dos fármacos , Colletotrichum/crescimento & desenvolvimento , Produtos Agrícolas , Grão Comestível , Fungicidas Industriais/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/patogenicidade , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Genes Fúngicos/genética , Família Multigênica , Mutação , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Óperon/genética , Controle Biológico de Vetores , Fenazinas/química , Fenazinas/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas chlororaphis/genética
11.
Pestic Biochem Physiol ; 150: 78-82, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30195391

RESUMO

Bacillus sp. 6256 is a good biocontrol agent against Botrytis cinerea which caused tomato gray mold disease. Strain 6256 was identified as B. amyloliquefaciens by analysis of its partial gyrB gene sequence. To identify and characterize the antimycotic peptides from the culture broth of the bacterium, the antimicrobial substances produced by B. amyloliquefaciens 6256 were isolated by ammonium sulfate precipitation, Superdex 200 gel filtration chromatography and DEAE anion exchange chromatography. The purified compound was designated as P657. The biological activity of P657 was stable at as high as 100 °C for 20 min and in pH value ranged from 5 to 10. The antimycotic compound was resistant to trypsin and proteinase K, and could completely inhibit spore germination of Botrytis cinerea in vitro. MALDI-TOF-MS analysis results showed the presence of fengycins A (C16-C17) and fengycins B (C15-C17) isoforms in P657.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Botrytis/efeitos dos fármacos , Micélio/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Botrytis/crescimento & desenvolvimento , Cromatografia DEAE-Celulose/métodos , Cromatografia em Gel/métodos , Concentração de Íons de Hidrogênio , Lycopersicon esculentum/microbiologia , Peptídeos/síntese química , Peptídeos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura Ambiente
12.
Lett Appl Microbiol ; 67(4): 400-410, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30022505

RESUMO

The antifungal properties of 12 Eos, that is, Syzygium aromaticum, Pelargonium graveolens, Lavandula angustifolia, Cupresus sempervirens, Mentha piperita, Santolina chamaecyparissus, Citrus sinensis, Pogostemon patchouli, Thymus mastichina, Thymus vulgaris, Eucalyptus globulus and Rosmarinus officinalis, were screened. The influence of five doses of each EOs was tested against Botrytis cinerea, Sclerotinia sclerotiorum, Fusarium oxysporum, Phytophthora parasitica, Pythium aphanidermatum, Alternaria brassicae, Cladobotryum mycophilum and Trichoderma aggressivum f.sp. europaeum using disc-diffusion method. The mycelial growth inhibition and ED50 were calculated. The chemical analysis of the EOs was analysed using gas chromatography-mass spectroscopy. A total of 58 compounds were identified in the 12 EOs. All essential oils (EOs) analysed showed antifungal activity against the test pathogens in the range of 5·32-100%. The inhibitory effect of oils showed dose-dependent activity on the tested fungus. Based on the ED50 values, clove, rose geranium, peppermint and patchouli were the most effective. This study warrants further research into the practical use of EOs for the control of important myco- and phytopathogens in intensive horticulture. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to the serious damage caused by fungal pathogens of vegetables and mushrooms, it is necessary to search for integrated strategies of disease control. This study provides relevant information about the effects of 12 essential oils (EOs) against eight pathogens of agricultural interest, included mycopathogens with emphasis on the possible future application of the EOs as alternative antifungal agents.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Fusarium/crescimento & desenvolvimento , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Verduras/microbiologia , Agaricales , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Citrus sinensis/química , Eucalyptus/química , Fusarium/efeitos dos fármacos , Lavandula/química , Testes de Sensibilidade Microbiana , Pelargonium/química , Pogostemon/química , Syzygium/química , Thymus (Planta)/química
13.
Microb Pathog ; 122: 98-107, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29894808

RESUMO

A total of 219 endophytic actinobacteria, isolated from roots, stems and leaves of chickpea, were characterized for antagonistic potential against Botrytis cinerea, causal organism of Botrytis grey mold (BGM) disease, in chickpea. Among them, three most potential endophytes, AUR2, AUR4 and ARR4 were further characterized for their plant growth-promoting (PGP) and nodulating potentials and host-plant resistance against B. cinerea, in chickpea. The sequences of 16 S rDNA gene of the three endophytes were matched with Streptomyces but different species. In planta, the isolate AUR4 alone was able to significantly enhance PGP traits including seed numbers (11.8 vs. 9.8/Plant), seed weight (8 vs. 6.8 g/Plant), pod numbers (13.6 vs. 11.5/Plant), pod weight (9.3 vs. 7.5 g/Plant) and biomass (10.9 vs. 8 g/Plant) over the un-inoculated control in chickpea genotype JG11. Interestingly, consortium of the selected endophytes, AUR2, AUR4 and ARR4 were found less effective than single inoculation. Co-inoculation of the selected endophytes with Mesorhizobium ciceri significantly enhanced nodulation and nitrogenase activity in five chickpea genotypes including ICCV2, ICCV10, ICC4958, Annigeri and JG11 over the un-inoculated control. The selected endophytes showed antagonistic potential in planta by significant reduction of disease incidence (28─52%) in both single inoculation and consortium treatments over the un-inoculated control across the genotypes ICC4954 (susceptible), ICCV05530 (moderately resistant) and JG11 (unknown resistance). Further, antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase, phenylalanine ammonia-lyase and polyphenol oxidase and phenolics were found induced in the leaves of chickpea inoculated with selected endophytes over un-inoculated control. Principal component analysis revealed that, the antioxidant enzymes and phenolics were found in the magnitude of ICC4954 < JG11 < ICCV05530 which correlates with their resistance level. The selected endophytes enhanced the plant growth and also host plant resistance against BGM in chickpea.


Assuntos
Botrytis/crescimento & desenvolvimento , Cicer/microbiologia , Endófitos/crescimento & desenvolvimento , Mesorhizobium/crescimento & desenvolvimento , Interações Microbianas , Doenças das Plantas/prevenção & controle , Streptomyces/crescimento & desenvolvimento , Cicer/crescimento & desenvolvimento , Cicer/imunologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Nitrogenase/análise , Filogenia , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Planta/metabolismo , Nodulação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/classificação , Streptomyces/genética , Streptomyces/isolamento & purificação
14.
Phytochemistry ; 154: 10-18, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29929021

RESUMO

A thorough study of the fermentation broth of three strains of Botrytis cinerea which were grown on a modified Czapek-Dox medium supplemented with 5 ppm copper sulphate, yielded five undescribed metabolites. These metabolites possessed a sesquiterpenoid (+)-4-epi-eremophil-9-ene carbon skeleton which was enantiomeric to that of the phytoalexin, capsidiol. The isolation of these metabolites when the fungus was stressed, suggests that they may be potential effectors used by B. cinerea to circumvent plant chemical defences against phytopathogenic fungi. The biosynthesis of these compounds has been studied using 2H and 13C labelled acetate.


Assuntos
Antifúngicos/farmacologia , Botrytis/química , Fungos/efeitos dos fármacos , Doenças das Plantas/microbiologia , Sesquiterpenos/farmacologia , Triterpenos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Botrytis/crescimento & desenvolvimento , Botrytis/metabolismo , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/metabolismo
15.
Molecules ; 23(7)2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29933580

RESUMO

A efficient 2-step protocol has been applied for the synthesis of Lansiumamide B (N-methyl-N-cis-styryl-cinnamamide, 2) derivatives by various substitution on the amide nitrogen with alkyl, allyl, propargyl, benzyl or ester groups. The structures of nine new compounds were characterized by HRMS, ¹H NMR, and 13C NMR spectra. These compounds were tested in vitro against 10 strains of phytopathogenic fungi and showed a wide antifungal spectrum. The relationship between different substituents on the amide nitrogen and antifungal activity of Lansiumamide B derivatives were compared and analyzed. The result indicates that the length and steric hindrance of N-substitution have a significant impact on biological activities. It is noteworthy that the methyl or ethyl substituent on the amide nitrogen is critical for the antifungal activities.


Assuntos
Botrytis/efeitos dos fármacos , Cinamatos/síntese química , Fungicidas Industriais/síntese química , Estirenos/síntese química , Alquilação , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Cinamatos/farmacologia , Ésteres , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Phytophthora/efeitos dos fármacos , Phytophthora/crescimento & desenvolvimento , Relação Estrutura-Atividade , Estirenos/farmacologia
16.
PLoS One ; 13(5): e0198411, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29852011

RESUMO

Pomegranate fruit consumption has increased rapidly throughout the world, mainly because of its medical and nutritive attributes. Thus, considerable commercial and scientific interest exists in prolonging its postharvest life with non-chemical applications as much as possible to meet the year-round demand for this fruit. The present work aimed to study the effects of black seed oil (0.1% and 0.5%), propolis (0.01% and 0.1%) and fludioxonil (0.06%), with and without modified atmosphere packaging (MAP), on the postharvest quality of pomegranate cv. Wonderful. Treated fruits were stored at 6.5±1 °C and 90-95% relative humidity for 150 days. The results indicated that both black seed oil and propolis treatments significantly influenced the maintenance of fruit weight and quality. At 150 days after storage, the fruit weight loss of the samples treated with MAP + 0.5% black seed oil, MAP + 0.1% propolis and MAP alone were found to be 5.5%, 6.3%, and 9.1%, respectively, whereas the weight loss of the untreated control fruits was 19.8%. Application of either 0.5% black seed oil or 0.1% propolis, especially when combined with MAP, was also effective in controlling gray mold development and slowing the occurrence of chilling injury.


Assuntos
Dioxóis/farmacologia , Qualidade dos Alimentos , Óleos Vegetais/farmacologia , Própole/farmacologia , Punicaceae/efeitos dos fármacos , Pirróis/farmacologia , Antocianinas/análise , Antioxidantes/análise , Ácido Ascórbico/análise , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Botrytis/fisiologia , Conservação de Alimentos , Punicaceae/química , Punicaceae/crescimento & desenvolvimento , Punicaceae/microbiologia , Temperatura Ambiente
17.
Microbiol Res ; 212-213: 1-9, 2018 Jul - Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29853163

RESUMO

This study aimed to investigate the mycoparasitism of Botrytis cinerea, the pathogen of scape and umbel blights of onion seed crops, by endophytic Talaromyces pinophilus. The dual culture test showed that the antagonistic potentiality of T. pinophilus against B. cinerea depend on the mycoparasitism that was morphologically detected by the formation of mycelial overgrowth. Moreover, the light micrograph of the mycelia at the contact zone exhibited that the hyphae of T. pinophilus penetrated and grew intracellularly inside the hyphae of B. cinerea. A more illustrative figure of the establishment of coiled hyphae as well as the conformation of the penetration process was assayed by SEM and TEM analyses. SEM micrograph revealed that the hyphae of T. pinophilus grew along hyphae of B. cinerea, attached, coiled around the host hypha and generated pseudoappressorium. A clear disintegration of cell wall of the host hypha was observed at the penetration site. The micrographs of TEM exhibited the ability of T. pinophilus to produce pseudoappressorium, penetrate and then entere a hypha of B. cinerea causing distinct cytoplasmic disorganization. High activities of cell wall degrading enzymes (chitinase, lipase and protease) involved in the mycoparasitism were evaluated by the endophytic T. pinophilus. In conclusion, this study demonstrated that the endophytic T. pinophilus may be a promising biocontrol agent against phytopathogenic fungi instead of chemical fungicides.


Assuntos
Antibiose , Botrytis/patogenicidade , Cebolas/microbiologia , Controle Biológico de Vetores , Doenças das Plantas/microbiologia , Talaromyces/fisiologia , Botrytis/citologia , Botrytis/crescimento & desenvolvimento , Botrytis/isolamento & purificação , Parede Celular , Quitinases/metabolismo , Técnicas de Cocultura , DNA Fúngico , Egito , Endófitos , Fungicidas Industriais , Hifas/citologia , Hifas/crescimento & desenvolvimento , Lipase/metabolismo , Microscopia Eletrônica , Micélio/crescimento & desenvolvimento , Peptídeo Hidrolases/metabolismo , Controle Biológico de Vetores/métodos , Talaromyces/citologia , Talaromyces/enzimologia , Talaromyces/isolamento & purificação
18.
Food Chem ; 262: 226-234, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29751914

RESUMO

A non-destructive method for detection of fungal contamination in peaches using an electronic nose (E-nose) is presented. Peaches were inoculated with three common spoilage fungi, Botrytis cinerea, Monilinia fructicola and Rhizopus stolonifer and then stored for various periods. E-nose was then used to analyze volatile compounds generated in the fungi-inoculated peaches, which was then compared with the growth data (colony counts) of the fungi. The results showed that changes in volatile compounds in fungi-inoculated peaches were correlated with total amounts and species of fungi. Terpenes and aromatic compounds were the main contributors to E-nose responses. While principle component analysis (PC1) scores were highly correlated with fungal colony counts, Partial Least Squares Regression (PLSR) could effectively be used to predict fungal colony counts in peach samples. The results also showed that the E-nose had high discrimination accuracy, demonstrating the potential use of E-nose to discriminate among fungal contamination in peaches.


Assuntos
Nariz Eletrônico , Fungos/isolamento & purificação , Prunus persica/microbiologia , Terpenos/análise , Ascomicetos/química , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Botrytis/química , Botrytis/crescimento & desenvolvimento , Botrytis/isolamento & purificação , Fungos/química , Fungos/crescimento & desenvolvimento , Rhizopus/química , Rhizopus/crescimento & desenvolvimento , Rhizopus/isolamento & purificação
19.
Enzyme Microb Technol ; 112: 35-42, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29499778

RESUMO

The use of cell wall degrading enzymes of Trichoderma is a promising alternative for improving food storage. The aspartic protease P6281 secreted by the fungus Trichoderma harzianum plays an important role in mycoparasitism on phytopathogenic fungi. In this study, recombinant P6281 (rP6281) expressed in Pichia pastoris showed high activity of 321.8 U/mL. Maximum activity was observed at pH 2.5 and 40 °C, and the enzyme was stable in the pH range of 2.5-6.0. rP6281 significantly inhibited spore germination and growth of plant and animal pathogenic fungi such as Botrytis cinerea, Mucor circinelloides, Aspergillus fumigatus, Aspergillus flavus, Rhizoctonia solani, and Candida albicans. Transmission electron microscopy revealed that rP6281 efficiently damages the cell wall of Botrytis cinerea. In addition, the protease significantly inhibited the development of grey mold that causes rotting of apple, orange, and cucumber, indicating that rP6281 may be developed as an effective anti-mold agent for fruit storage.


Assuntos
Ácido Aspártico Proteases/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/patogenicidade , Trichoderma/enzimologia , Antifúngicos/farmacologia , Ácido Aspártico Proteases/genética , Ácido Aspártico Proteases/farmacologia , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Botrytis/patogenicidade , Parede Celular/efeitos dos fármacos , Parede Celular/ultraestrutura , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Armazenamento de Alimentos , Proteínas Fúngicas/genética , Proteínas Fúngicas/farmacologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Genes Fúngicos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Trichoderma/genética
20.
Lett Appl Microbiol ; 66(5): 455-461, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29495073

RESUMO

The aim of the present work was to evaluate the ability of the native yeast Rhodosporidium fluviale to control Botrytis cinerea on apple fruit and to study the possible mechanisms of action with the goal of improving the control of gray mold. For this, the influence of application time of the yeast was studied simulating preventive and curative effects. Also, the effect of nonviable cells of the yeast in the biocontrol was assessed. According to the results obtained, the following mechanisms of action of R. fluviale could be proposed: 1- competition for space, 2- direct interaction between antagonist and pathogen, 3- induction of ß-1,3-glucanase in apple tissue, 4- Probable production of glucanase in the apple wounds and 5- antifungal action of cellular components, probably chitin, present in the wall of yeast cells that could be the explanation for the activity of nonviable cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Significance and Impact of the Study: Botrytis cinerea Pers: Fr, which causes gray mold of fruits and vegetables around the world, is difficult to control successfully because it is genetically variable and rapidly develops resistance to the chemicals commonly used for its control. This study is a contribution to the biocontrol of this phytopathogen fungus. The evaluation of the native yeast Rhodosporidium fluviale as biocontrol agent and the elucidation of possible mechanisms of action, including the participation of nonviable cells of this yeast, have not been reported up to date.


Assuntos
Antibiose/fisiologia , Antifúngicos/metabolismo , Basidiomycota/metabolismo , Agentes de Controle Biológico/metabolismo , Botrytis/crescimento & desenvolvimento , Malus/microbiologia , Argentina , Frutas/microbiologia , Doenças das Plantas/microbiologia
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