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1.
Mycologia ; 114(5): 900-913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35929963

RESUMO

A Polystigma-like found on an herbaceous to shrubby species of Fabaceae (Andira humilis) in the Brazilian Cerrado was morphologically close to Polystigma pusillum, a leaf parasite on Andira inermis collected in Central America and Brazil. Phylogenetic analyses using a combination of the rDNA 28S, 18S, and internal transcribed spacer (ITS) regions placed both fungi in the Phyllachorales, and not in Polystigamataceae/Xylariales, where Polystigma species belong, and characteristically found on members of the Rosaceae, causing red leaf blotch containing bright-colored fungal stromata spread on the lesions. This disease prevails in orchards in the Northern Hemisphere, infecting Amygdalus, Cerasus, Padus, and Prunus species, but never in the Tropics. Polystigma species infecting other botanical families have been reallocated in different families, orders, and even classes in Ascomycota. In our phylogenetic analyses, the two species on Andira were allocated in Phyllachorales but separated in a well-supported cluster from Phyllachoraceae and Phaeochoraceae. In relation to Telimenaceae, the statistical support is not strong; however, considering that its type genus, Telimena, was never sequenced, we choose to accept Neopolystigma (type N. saraivae) as the type genus of a new family, Neopolystigmataceae. The sister species of N. saraivae, Polystigma pusillum found on A. inermis, was recombined into N. pusillum.


Assuntos
Ascomicetos , Prunus , Ascomicetos/genética , DNA Fúngico/genética , Humanos , Phyllachorales , Filogenia , Análise de Sequência de DNA
2.
Int J Mol Sci ; 23(11)2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35683002

RESUMO

Glomerella leaf spot (GLS), caused by the fungus Colletotrichum fructicola, is one of the most devastating apple diseases. Our previous study reported that the GLS resistance locus was defined on the chromosome 15 region. Here, we further found a single-nucleotide polymorphism (SNP) site (SNP7309212) in the GLS resistance that was able to distinguish resistant cultivars (lines) from susceptible ones. On the basis of the SNP site, we cloned a TNL gene from the GLS resistant locus and named it MdTNL1 (NCBI Accession Number: ON402514). This gene contains a toll/interleukin-1 receptor transmembrane domain (TIR), nucleotide-binding sites (NBS), and leucine-rich repeat (LRR) domain. Subcellular location indicated that MdTNL1 was expressed in the nucleus and cell membrane. Ectopic overexpression of MdTNL1 in Nicotiana benthamiana caused cell death. We further demonstrated allelic polymorphisms in MdTNL1. It is noteworthy that NBS and LRR domains of the MdTNL1 protein serve as the repository for generating allelic diversity. Quantitative real-time PCR (qRT-PCR) assay revealed that MdTNL1 was highly expressed in resistant apple cultivar 'Fuji' after inoculation with C. fructicola, whereas susceptible cultivar 'Golden Delicious' exhibited low expression after inoculation. Over-expression of MdTNL1-1 in susceptible apple fruits and leaves improved disease resistance, while in 'Orin' calli, silencing the MdTNL1-1 gene conversely decreased GLS resistance. In conclusion, we identified a GLS associated with SNP7309212 and demonstrated that a TIR-NBS-LRR gene MdTNL1-1 positively regulates GLS resistance in apple.


Assuntos
Malus , Sítios de Ligação , Resistência à Doença/genética , Malus/metabolismo , Nucleotídeos , Phyllachorales/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo
3.
Phytopathology ; 112(9): 1825-1832, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35322713

RESUMO

Glomerella leaf spot (GLS) is one of the most important diseases of apple, affecting a wide range of economically important cultivars, particularly Golden Delicious and its descendants. Caused mainly by species of the Colletotrichum gloeosporioides species complex (CGSC), C. fructicola has been described as the most prevalent and aggressive species associated with GLS and apple bitter rot (ABR) in Brazil and Uruguay. Recently, new CGSC species, closely related to C. fructicola, have been identified causing ABR. To verify the accuracy of species identification within the CGSC, we aimed to reevaluate the identity of representative GLS-causing isolates from Brazilian and Uruguayan populations, previously identified as C. fructicola. Multilocus phylogenetic analysis based on APN2, ApMAT, CAL, GAPDH, GS, ITS, and TUB2 allocated these isolates in a monophyletic clade with C. chrysophilum. This species was first described as the causal agent of anthracnose in banana fruits in Brazil, and recent reports indicate its association with ABR in the United States. This is the first report of C. chrysophilum causing GLS disease on apple worldwide.


Assuntos
Colletotrichum , Malus , Brasil , Besouros , Colletotrichum/genética , Phyllachorales , Filogenia , Doenças das Plantas , Uruguai
4.
BMC Genomics ; 23(1): 246, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35354401

RESUMO

BACKGROUND: Apple Glomerella leaf spot (GLS) and apple bitter rot (ABR) are two devastating foliar and fruit diseases on apples. The different symptoms of GLS and ABR could be related to different transcriptome patterns. Thus, the objectives of this study were to compare the transcriptome profiles of Colletotrichum gloeosporioides species complex isolates GC20190701, FL180903, and FL180906, the pathogen of GLS and ABR, and to evaluate the involvement of the genes on pathogenicity. RESULTS: A relatively large difference was discovered between the GLS-isolate GC20190701 and ABR-isolates FL180903, FL180906, and quite many differential expression genes associated with pathogenicity were revealed. The DEGs between the GLS- and ABR-isolate were significantly enriched in GO terms of secondary metabolites, however, the categories of degradation of various cell wall components did not. Many genes associated with secondary metabolism were revealed. A total of 17 Cytochrome P450s (CYP), 11 of which were up-regulated while six were down-regulated, and five up-regulated methyltransferase genes were discovered. The genes associated with the secretion of extracellular enzymes and melanin accumulation were up-regulated. Four genes associated with the degradation of the host cell wall, three genes involved in the degradation of cellulose, and one gene involved in the degradation of xylan were revealed and all up-regulated. In addition, genes involved in melanin syntheses, such as tyrosinase and glucosyltransferase, were highly up-regulated. CONCLUSIONS: The penetration ability, pathogenicity of GLS-isolate was greater than that of ABR-isolate, which might indicate that GLS-isolate originated from ABR-isolates by mutation. These results contributed to highlighting the importance to investigate such DEGs between GLS- and ABR-isolate in depth.


Assuntos
Colletotrichum , Malus , Animais , Colletotrichum/genética , Perfilação da Expressão Gênica , Malus/genética , Phyllachorales/genética , Transcriptoma
5.
PLoS Negl Trop Dis ; 15(9): e0009767, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34587171

RESUMO

Vector Borne Diseases (VBDs) are considered emerging and re-emerging diseases that represent a global burden. The aim of this study was to explore and characterize vector-borne pathogens in different domestic animal hosts in Egypt. A total of 557 blood samples were collected from different animals using a convenience sampling strategy (203 dogs, 149 camels, 88 cattle, 26 buffaloes, 58 sheep and 33 goats). All samples were tested for multiple pathogens using quantitative PCR and standard PCR coupled with sequencing. We identified Theileria annulata and Babesia bigemina in cattle (15.9 and 1.1%, respectively), T. ovis in sheep and buffaloes (8.6 and 7.7%, respectively) and Ba. canis in dogs (0.5%) as well as Anaplasma marginale in cattle, sheep and camels (20.4, 3.4 and 0.7%, respectively) and Coxiella burnetii in sheep and goats (1.7 and 3%; respectively). New genotypes of An. centrale, An. ovis, An. platys-like and Borrelia theileri were found in cattle (1.1,3.4, 3.4 and 3.4%, respectively), An. platys-like in buffaloes (7.7%), An. marginale, An. ovis, An. platys-like and Bo. theileri in sheep (3.4, 1.7, 1.7 and 3.4%, respectively), An. platys, An. platys-like and Setaria digitata in camels (0.7, 5.4 and 0.7%, respectively) and Rickettsia africae-like, An. platys, Dirofilaria repens and Acanthocheilonema reconditum in dogs (1.5, 3.4, 1 and 0.5%, respectively). Co-infections were found in cattle, sheep and dogs (5.7, 1.7, 0.5%, respectively). For the first time, we have demonstrated the presence of several vector-borne zoonoses in the blood of domestic animals in Egypt. Dogs and ruminants seem to play a significant role in the epidemiological cycle of VBDs.


Assuntos
Animais Domésticos , Babesia/isolamento & purificação , Bactérias/isolamento & purificação , Filarioidea/isolamento & purificação , Doenças Transmitidas por Vetores/veterinária , Animais , Babesia/genética , Bactérias/genética , Infecções Bacterianas/sangue , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/veterinária , Estudos Transversais , Egito/epidemiologia , Filariose/epidemiologia , Filariose/parasitologia , Filariose/veterinária , Phyllachorales , Prevalência , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Doenças Transmitidas por Vetores/sangue , Doenças Transmitidas por Vetores/epidemiologia
6.
Arch Virol ; 166(6): 1759-1762, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33745066

RESUMO

The whole genome sequence of a begomovirus (family Geminiviridae) infecting Muntingia calabura L. (family Muntingiaceae) from the province of Guayas in Ecuador was determined in this work. The major symptom observed on this plant species was yellow spots on leaves. The nucleotide sequences of three DNA-A clones and one DNA-B clone were compared to those of other begomoviruses. The DNA-A clones displayed the highest similarity to isolates of pepper leafroll virus (PepLRV), with 87.4 to 88.1% sequence identity. Likewise, the DNA-B clone showed the highest similarity (79.3-79.6% sequence identity) to PepLRV isolates. According to the demarcation criteria for begomovirus species, the begomovirus described in this work, for which we propose the name "muntingia yellow spot virus", represents a novel species. To our best knowledge, this is the first report of a begomovirus infecting a plant of the family Muntingiaceae.


Assuntos
Begomovirus/genética , Doenças das Plantas/virologia , Plantas/virologia , Begomovirus/isolamento & purificação , DNA Viral/genética , Equador , Phyllachorales
7.
Plant Dis ; 105(4): 940-947, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33021910

RESUMO

Red leaf blotch (RLB) of almond, caused by Polystigma amygdalinum, is an important foliar disease of this nut tree in the Mediterranean basin and Middle East regions. In recent years, the incidence of this disease has increased in Spain, corresponding to increases in the area of newly planted orchards and the use of susceptible cultivars. In 2009, an experimental orchard including 21 almond cultivars was planted at Les Borges Blanques, Lleida, in northeastern Spain. No fungicide treatments were applied during the 10-year experimental period (2009 to 2018) in order to allow natural disease development. Cultivar susceptibility to RLB was assessed each year, from 2011 to 2018, through visual observations of symptoms in naturally infected trees. The experimental results led us to classify the cultivars into five susceptibility groups. The most susceptible were Tarraco, Guara, Tuono, Marinada, Desmayo Largueta, and Soleta, whereas Mardía was the most tolerant. The annual incidence of disease was positively correlated with accumulated rainfall in spring, and especially in April, while it was negatively correlated with high spring and summer temperatures, especially in May. These findings could be used to improve disease management strategies by identifying the most susceptible cultivars and improving the timing of fungicide application.


Assuntos
Prunus dulcis , Oriente Médio , Phyllachorales , Folhas de Planta , Espanha
8.
Bioorg Chem ; 104: 104313, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142425

RESUMO

Glomerella fusaroide, and Rhizopus stolonifer were effectively able to transform the steroidal hormone melengestrol acetate (MGA) (1) into four (4) new metabolites, 17α-acetoxy-11α-hydroxy-6-methyl-16-methylenepregna-4,6-diene-3,20-dione (2), 17α-acetoxy-11α-hydroxy-6-methyl-16-methylenepregna-1,4,6-triene-3,20-dione (3), 17α-acetoxy-6,7α-epoxy-6ß-methyl-16-methylenepregna-4,6-diene-3,20-dione (4), and 17α-acetoxy-11ß,15ß-dihydroxy-6-methyl-16-methylenepregna-4,6-diene-3,20-dione (5). All these compounds were structurally characterized by different spectroscopic techniques. The objective of the current study was to assess the anti-inflammatory potential of melengestrol acetate (1), and its metabolites 2-5. The metabolites and the substrate were assessed for their inhibitory effects on proliferation of T-cells in vitro. The substrate (IC50 = 2.77 ± 0.08 µM) and its metabolites 2 (IC50 = 2.78 ± 0.07 µM), 4 (IC50 = 2.74 ± 0.1 µM), and 5 (IC50 = < 2 µM) exhibited potent T- cell proliferation inhibitory activities, while compound 3 (IC50 = 29.9 ± 0.09 µM) showed a moderate activity in comparison to the standard prednisolone (IC50 = 9.73 ± 0.08 µM). All the metabolites were found to be non-toxic against 3T3 normal cell line. This study thus identifies some potent compounds active against T-cell proliferation. Their anti-inflammatory potential, therefore, deserves to be further investigated.


Assuntos
Acetato de Melengestrol/farmacologia , Phyllachorales/metabolismo , Rhizopus/metabolismo , Linfócitos T/efeitos dos fármacos , Células 3T3 , Animais , Biotransformação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fermentação , Humanos , Acetato de Melengestrol/química , Acetato de Melengestrol/metabolismo , Camundongos , Estrutura Molecular , Phyllachorales/química , Rhizopus/química , Sementes/química , Sementes/metabolismo , Relação Estrutura-Atividade
9.
Appl Environ Microbiol ; 87(1)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067192

RESUMO

Glomerella leaf spot (GLS), caused by Colletotrichum fructicola, is a rapidly emerging disease leading to defoliation, fruit spot, and storage fruit rot on apple in China. Little is known about the mechanisms of GLS pathogenesis. Early transcriptome analysis revealed that expression of the zinc finger transcription factor Ste12 gene in C. fructicola (CfSte12) was upregulated in appressoria and leaf infection. To investigate functions of CfSte12 during pathogenesis, we constructed gene deletion mutants (ΔCfSte12) by homologous recombination. Phenotypic analysis revealed that CfSte12 was involved in pathogenesis of nonwounded apple fruit and leaf, as well as wounded apple fruit. Subsequent histological studies revealed that loss of pathogenicity by ΔCfSte12 on apple leaf was expressed as defects of conidium germination, appressorium development, and appressorium-mediated penetration. Further RNA sequencing-based transcriptome comparison revealed that CfSte12 modulates the expression of genes related to appressorium function (e.g., genes for the tetraspanin PLS1, Gas1-like proteins, cutinases, and melanin biosynthesis) and candidate effectors likely involved in plant interaction. In sum, our results demonstrated that CfSte12 is a key regulator of early apple GLS pathogenesis in C. fructicola In addition, CfSte12 is also needed for sexual development of perithecia and ascospores.IMPORTANCE Glomerella leaf spot (GLS) is an emerging fungal disease of apple that causes huge economic losses in Asia, North America, and South America. The damage inflicted by GLS manifests in rapid necrosis of leaves, severe defoliation, and necrotic spot on the fruit surface. However, few studies have addressed mechanisms of GLS pathogenesis. In this study, we identified and characterized a key pathogenicity-related transcription factor, CfSte12, of Colletotrichum fructicola that contributes to GLS pathogenesis. We provide evidence that the CfSte12 protein regulates many important pathogenic processes of GLS, including conidium germination, appressorium formation, appressorium-mediated penetration, and colonization. CfSte12 also impacts development of structures needed for sexual reproduction which are vital for the GLS disease cycle. These results reveal a key pathogenicity-related transcription factor, CfSte12, in C. fructicola that causes GLS.


Assuntos
Colletotrichum/fisiologia , Proteínas Fúngicas/genética , Malus/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Fatores de Transcrição/genética , Colletotrichum/genética , Proteínas Fúngicas/metabolismo , Phyllachorales/fisiologia , Fatores de Transcrição/metabolismo
10.
J Exp Zool B Mol Dev Evol ; 334(4): 235-244, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32150339

RESUMO

T-cell immunoglobulin (Ig) and mucin domain-containing 1 (Tim-1) and Tim-4 are two members of the Tim family. In mammals, Tim-1 and Tim-4 are proteins mainly expressed in immune cells and are associated with immune response. In the present study, medaka Oryzias latipes' Tim-1 (OlTim-1) and OlTim-4 were identified and characterized using bioinformatics analyses. With the use of reverse-transcription polymerase chain reaction, the expression profiles of OlTim-1 and OlTim-4 were examined in embryos and adult fish and in immune tissues following the intraperitoneal injection of stimulants. The results revealed that OlTim-1 possesses a cytoplasmic region, a transmembrane region, a mucin domain, and an Ig-like domain, while OlTim-4 is composed of two Ig-like domains and a mucin domain, but without the transmembrane region and cytoplasmic region. OlTim-1 and OlTim-4 expressions are detectable from the gastrula stage on, indicating that they are zygotic genes. Furthermore, OlTim-1 and OlTim-4 are expressed ubiquitously in the adult. Administration of immune stimulants, namely lipopolysaccharides and polyinosinic:polycytidylic acid, significantly increased the expression levels of OlTim-1 and OlTim-4 in the liver and intestine within 1 day and in the head, kidney, and spleen within 3 to 4 days postinjection. These results suggest that OlTim-1 and OlTim-4 are possibly involved in both innate and adaptive immunities.


Assuntos
Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Oryzias/metabolismo , Envelhecimento/fisiologia , Animais , Embrião não Mamífero/metabolismo , Receptor Celular 1 do Vírus da Hepatite A/genética , Modelos Moleculares , Oryzias/embriologia , Phyllachorales , Conformação Proteica
11.
J Exp Zool B Mol Dev Evol ; 334(1): 25-36, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31743605

RESUMO

Opsins play important roles in the image-forming visual pathways and numerous biological systems such as the biological clock and circadian rhythm. However, the nonvisual opsins involved in nonimage forming process are not clear to date. The aim of this study was to characterize nonvisual opsins in Paralichthys olivaceus. A total of 24 nonvisual opsin genes were identified. Expressions of these genes in eye, brain, heart, testis, and fin were investigated by quantitative real-time polymerase chain reaction (qRT-PCR). Testis contained a surprisingly large number of nonvisual opsins including Opn4m2, Tmt2a, Tmt3b, Opn3, RRH, Opn7a, and Opn7b. Syntenic and phylogenetic analyses confirmed that the RGRa and RGRb originated from the teleost-specific genome duplication (TSGD). qRT-PCR results demonstrated high RGRa and RGRb expression in the eye, while the expression levels in the brain, heart, testis, and fin were relatively weak. In situ hybridization results presented here revealed the presence of both RGRa and RGRb mRNA-positive signals in the ganglion cell layer but absence in the intracellular compartment of retinal pigment epithelium (RPE) and Müller glial cells. Therefore, we hypothesized that RGRa and RGRb had undergone subfunctionalization in P. olivaceus after TSGD. In conclusion, this study provides novel insights into the evolutionary fates of the RGR genes, still, further studies need to be done to explore the mechanism about the lack of RGR genes' expression in RPE.


Assuntos
Proteínas do Olho/metabolismo , Linguados/metabolismo , Estudo de Associação Genômica Ampla , Opsinas/genética , Receptores Acoplados a Proteínas G/metabolismo , Animais , Proteínas do Olho/genética , Regulação da Expressão Gênica , Opsinas/metabolismo , Phyllachorales , Receptores Acoplados a Proteínas G/genética , Distribuição Tecidual , Transcriptoma
12.
Emerg Infect Dis ; 26(1): 168-171, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855532

RESUMO

Influenza D virus (IDV) can potentially cause respiratory diseases in livestock. We isolated a new IDV strain from diseased cattle in Japan; this strain is phylogenetically and antigenically distinguished from the previously described IDVs.


Assuntos
Doenças dos Bovinos/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Thogotovirus/genética , Animais , Bovinos/virologia , Doenças dos Bovinos/virologia , Japão/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Phyllachorales , Reação em Cadeia da Polimerase em Tempo Real/veterinária
13.
Mycologia ; 111(4): 660-675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150307

RESUMO

Species of Phaeochorella are biotrophic leaf parasites with a tropical distribution, traditionally accepted in the family Phyllachoraceae, Phyllachorales in classifications based on morphological characters. Phylogenetic evidence presented here resolves the relationship of Phaeochorella within the Sordariomycetes, based on a multilocus analysis of partial nuc rDNA large subunit (28S) and internal transcribed spacers (ITS1-5.8S-ITS2 = ITS), the DNA-directed RNA polymerase II second largest subunit (RPB2), and the translation elongation factor 1-α (TEF1-α) gene. Phylogenetic analyses indicate that Phaeochorella belongs to the Diaporthales rather than the Phyllachorales. Phaeochorella parinarii, the type species of the genus, present on native hosts from the Brazilian Cerrado, forms a unique clade with a species of Phaeoappendicospora with high support. Thus, a new family, Phaeochorellaceae, Diaporthales, including both genera, is herein proposed. With the exception of P. parinarii and P. zonata, all other species in Phaeochorella (P. artocarpi, P. ciliata, P. machaerii) were excluded from the genus.


Assuntos
Phyllachorales/classificação , Phyllachorales/isolamento & purificação , Filogenia , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Brasil , DNA Fúngico/genética , Phyllachorales/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética
14.
J Plant Physiol ; 236: 96-104, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30939334

RESUMO

The red leaf blotch (RLB) of almond, caused by the fungus Polystigma amygdalinum, is considered as one of the most important leaf diseases of this fruit tree. Differential cultivar susceptibility to the RLB has been described based on field observations, while its molecular and biochemical bases remain unknown to date. We aimed to explore the plant defence mechanisms related to the cultivar susceptibility by identifying some relevant physical and chemical strategies for the pathogen control. Thus, we studied the regulation of seven defence-related genes as well as the lignin deposition in two almond cultivars with highly differential response to RLB: the highly tolerant 'Mardía' and the susceptible 'Tarraco' cultivars. 'Mardía' displayed an up-regulation of the CAD and DFN1 genes at early stages of RLB symptom expression, with further lignin deposition in the fungal-colonized area that was visualized by microscopy. Thus, 'Mardía' uses both physical and chemical responses to effectively repress the pathogen. In contrast, 'Tarraco' triggered the up-regulation of HQT and LDOX genes, related to chlorogenic acid and anthocyanin biosynthesis pathways, respectively, while lignin deposition was not clearly noticed. This strategy recorded in 'Tarraco' at later stages of RLB symptoms failed to control the fungal infection and colonization. Our results suggested a major role of the phenylpropanoids pathway in the defence response against RLB, by showing that an early production of lignin might be a major mechanism to control the spread of P. amygdalinum within the host leaf tissues.


Assuntos
Lignina/metabolismo , Phyllachorales , Doenças das Plantas/microbiologia , Imunidade Vegetal , Prunus dulcis/microbiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas/imunologia , Doenças das Plantas/imunologia , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Prunus dulcis/imunologia , Prunus dulcis/metabolismo , Transcriptoma
15.
Ecotoxicol Environ Saf ; 169: 207-215, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30448703

RESUMO

Mancozeb is a fungicide widely used in agriculture, mostly against the pathogen Glomerella cingulata responsible for the rot of ripe grape, but presents high toxicity. Strategies are sought to reduce the toxicity of this fungicide and alternative treatments are welcome. An alternative could be the use of clove oil, which has Eugenol as its major compound, and has antifungal potential against G. cingulata, however, Eugenol is susceptible to degradation processes which may compromise its efficacy. The nanoencapsulation of Mancozeb and Eugenol is a possible strategy to overcome the limitations of toxicity, solubility and instability of these compounds. Therefore, the objective of this study is to develop nanoemulsions containing Mancozeb (0.1 mg/mL) and Eugenol (33 mg/mL), isolated or associated, and evaluate the safety of these formulations through cytotoxicity, genotoxicity and ecotoxicity tests. Nanoemulsions were developed by the spontaneous emulsification method, cytotoxicity and genotoxicity were evaluated in healthy human cells through MTT, Dichlorofluorescein diacetate and Picogreen tests, and ecotoxicity assessment was carried out using the chronic toxicity test in springtails. After preparation, the physicochemical characterization of the nanoemulsions were performed which presented mean particle size between 200 and 300 nm, polydispersity index less than 0.3, negative zeta potential and acid pH. The nanoencapsulation was able to avoid the reduction of the cell viability caused by Mancozeb, while Eugenol was shown to be safe for cell use in both free and nanostructured forms, however the association of the two active compounds showed toxicity in the higher doses of Mancozeb. In the ecotoxicity tests, both free Mancozeb and Eugenol forms presented high toxic potential for soil, whereas the nanoencapsulation of these compounds did not cause a reduction in number of springtails. Therefore, from the tests performed, it was possible to observe that nanoencapsulation of Mancozeb and Eugenol is a safe alternative for the application of these compounds mainly in agriculture.


Assuntos
Artrópodes/efeitos dos fármacos , Dano ao DNA , Eugenol/toxicidade , Fungicidas Industriais/toxicidade , Maneb/toxicidade , Nanocápsulas/toxicidade , Zineb/toxicidade , Animais , Artrópodes/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Emulsões , Eugenol/química , Fungicidas Industriais/química , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Maneb/química , Nanocápsulas/química , Tamanho da Partícula , Phyllachorales/efeitos dos fármacos , Solo/química , Testes de Toxicidade , Zineb/química
16.
Plant Biol (Stuttg) ; 21(2): 318-325, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30449064

RESUMO

We recently discovered that ß-aminobutyric acid (BABA), a molecule known for its ability to prime defences in plants, is a natural plant metabolite. However, the role played by endogenous BABA in plants is currently unknown. In this study we investigated the systemic accumulation of BABA during pathogen infection, levels of BABA during plant growth and development and analysed mutants possibly involved in BABA transport or regulation. BABA was quantified by LC-MS using an improved method adapted from a previously published protocol. Systemic accumulation of BABA was determined by analysing non-infected leaves and roots after localised infections with Plectosphaerella cucumerina or Pseudomonas syringae pv. tomato (Pst) DC3000 avrRpt2. The levels of BABA were also quantified in different plant tissues and organs during normal plant growth, and in leaves during senescence. Mutants affecting amino acid transport (aap6, aap3, prot1 and gat1), γ-aminobutyric acid levels (pop2) and senescence/defence (cpr5-2) were analysed. BABA was found to accumulate only locally after bacterial or fungal infection, with no detectable increase in non-infected systemic plant parts. In leaves, BABA content increased during natural and induced senescence. Reproductive organs had the highest levels of BABA, and the mutant cpr5-2 produced constitutively high levels of BABA. Synthetic BABA is highly mobile in the receiving plant, whereas endogenous BABA appears to be produced and accumulated locally in a tissue-specific way. We discuss a possible role for BABA in age-related resistance and propose a comprehensive model for endogenous and synthetic BABA.


Assuntos
Aminobutiratos/metabolismo , Arabidopsis/crescimento & desenvolvimento , Imunidade Vegetal , Arabidopsis/metabolismo , Phyllachorales , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Pseudomonas syringae
17.
Pest Manag Sci ; 75(4): 1123-1130, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30284404

RESUMO

BACKGROUND: Natural stilbenes (especially resveratrol and its derivatives) are well-known phytoalexins that are active against many plant diseases. However, oxidative degradation and low bioavailability limit their exogenous application as fungicides on crops. In this study, a new class of resveratrol-inspired thiophene-based stilbene derivatives bearing an 1,3,4-oxadiazole unit was synthesized and the derivatives' antifungal activities against phytopathogenic fungi were investigated. RESULTS: The results revealed that compounds 5h and 5j exhibited improved antifungal activity against Botrytis cinerea with median effective concentrations (EC50 ) of 168.5 and 155.4 µg mL-1 , respectively, which were superior to the EC50 of resveratrol (263.1 µg mL-1 ). Compound 5j was shown to effectively control disease development in B. cinerea-infected tomatoes in vivo. Notably, considerably abnormal mycelial morphology and increased cell membrane conductivity were observed in the presence of compound 5j. CONCLUSION: A new class of thiophene-containing stilbene derivatives was designed and synthesized. Bioassay results showed that compound 5j exhibited promising antifungal activity, suggesting practical potential for fungal disease control. © 2018 Society of Chemical Industry.


Assuntos
Botrytis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Phyllachorales/efeitos dos fármacos , Estilbenos/síntese química , Estilbenos/farmacologia , Fungicidas Industriais/síntese química , Testes de Sensibilidade Microbiana , Oxidiazóis/química , Tiofenos/química
18.
Comb Chem High Throughput Screen ; 21(7): 501-509, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30255746

RESUMO

AIM AND OBJECTIVE: Plant diseases are caused by fungal pathogens lead to severe economic losses in many agriculture crops. And the increasing resistance of many fungi to commonly used antifungal agents necessitates the discovery and development of new fungicides. So this study was focused on synthesizing novel skeleton compounds to effectively control plant diseases. MATERIALS AND METHODS: A series of drimane-amide derivatives were designed, synthesized by aminolysis reaction of amine with intermediate sclareolide which was prepared from sclareol. The structures of all the synthesized compounds were confirmed using 1H NMR, 13C NMR, and HRMS (ESI) spectroscopic data. Their in vitro antifungal activity were preliminarily evaluated by using the mycelium growth rate method against five phytopathogenic fungi: Botrytis cinerea, Glomerella cingulata, Alternaria alternate, Alternaria brassicae, and Fusarium graminearum. RESULTS: 23 target compounds were successfully obtained in yields of 52-95%. Compounds A2 and A3 displayed favorable inhibitory potency against B. cinerea, G. cingulata and A. brassicae with IC50 values ranging from 3.18 to 10.48 µg/mL. These two compounds displayed higher fungicidal activity than sclareol against all the tested phytopathogenic fungi, and were more effective than the positive control thiabendazole against A. alternate and A. brassicae. The structure-activity relationship studies of compounds A1-10 indicated that both the position and type of substituent on the phenyl ring had significant effects on antifungal activity. CONCLUSION: The drimane-amide derivatives A2 and A3 were the most promising derivatives and should be selected as new templates for the potential antifungal agents.


Assuntos
Amidas/farmacologia , Antifúngicos/farmacologia , Diterpenos/química , Sesquiterpenos/farmacologia , Alternaria/efeitos dos fármacos , Amidas/síntese química , Amidas/química , Antifúngicos/síntese química , Antifúngicos/química , Botrytis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Testes de Sensibilidade Microbiana , Phyllachorales/efeitos dos fármacos , Sesquiterpenos Policíclicos , Sesquiterpenos/síntese química , Sesquiterpenos/química , Relação Estrutura-Atividade
19.
Mycologia ; 110(5): 835-859, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30215574

RESUMO

Species of tropical tar spot fungi (Phyllachorales, Ascomycota) are obligate biotrophic plant parasitic fungi associated with living leaves of a wide range of families of host plants, mainly in tropical and subtropical regions. In this study, samples of tropical tar spot fungi were collected in forests in Costa Rica and Panamá. To identify taxa, we used morphology and information on host plants and combined multigene phylogeny of four genes: the large subunit nuclear ribosomal DNA (28S rDNA), the small subunit nuclear ribosomal DNA (18S rDNA), the complete internal transcribed spacer region of ribosomal DNA (nuc rDNA ITS1-5.8S-ITS2; ITS), and the translation elongation factor 1-α (tef1). Here we propose one new species in the genus Camarotella and eight new species in Telimena with their morphological descriptions, illustrations, and sequence data. The newly described species are Camarotella licaniae on Licania arborea (Chrysobalanaceae) and in the genus Telimena: T. billiae on Billia rosea (Sapindaceae), T. drymoniae on Drymonia multiflora (Gesneriaceae), T. hydrangeae on Hydrangea sp. (Hydrangeaceae), T. miravallensis on Symplocos panamensis (Symplocaceae), T. protii on Protium sp. (Burseraceae), T. rinoreae on Rinorea sp. (Violaceae), T. semialarii on Semialarium mexicanum (Celastraceae), and T. triseptata on Tapirira mexicana (Anacardiaceae). The new name Telimena nitens on Schlegelia brachyanta (Schlegeliaceae) is presented and 10 species of Phyllachora are transferred to Telimena, leading to the new combinations T. canarii, T. galavisii, T. insueta, T. ruelliae, T. scutiformis, T. serjaniicola, T. spicatae, T. subrepens, T. symploci, and T. symplocicola. Additionally, revisions of tar spot fungi on host families Burseraceae, Sapindaceae, and Symplocaceae are provided, and four new synonyms are proposed.


Assuntos
Carpóforos/crescimento & desenvolvimento , Phyllachorales/classificação , Phyllachorales/isolamento & purificação , Filogenia , Análise por Conglomerados , Costa Rica , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Microscopia , Microscopia de Contraste de Fase , Panamá , Fator 1 de Elongação de Peptídeos/genética , Phyllachorales/genética , Doenças das Plantas/microbiologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
20.
Ann Bot ; 121(6): 1211-1230, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29471367

RESUMO

Background and Aims: The genetic basis of fruit development has been extensively studied in Arabidopsis, where major transcription factors controlling valve identity (i.e. FRUITFULL), replum development (i.e. REPLUMLESS) and the differentiation of the dehiscence zones (i.e. SHATTERPROOF, INDEHISCENT and ALCATRAZ) have been identified. This gene regulatory network in other flowering plants is influenced by duplication events during angiosperm diversification. Here we aim to characterize candidate fruit development genes in the Solanaceae and compare them with those of Brassicaceae. Methods: ALC/SPT, HEC/IND, RPL and AG/SHP homologues were isolated from publicly available databases and from our own transcriptomes of Brunfelsia australis and Streptosolen jamesonii. Maximum likelihood phylogenetic analyses were performed for each of the gene lineages. Shifts in protein motifs, as well as expression patterns of all identified homologues, are shown in dissected floral organs and fruits in different developmental stages of four Solanaceae species exhibiting different fruit types. Key Results: Each gene lineage has undergone different duplication time-points, resulting in very different genetic complements in the Solanaceae when compared with the Brassicaceae. In general, Solanaceae species have more copies of HEC1/2 and RPL than Brassicaceae, have fewer copies of SHP and the same number of copies of AG, ALC and SPT. Solanaceae lack IND orthologues, but have pre-duplication HEC3 homologues. The expression analyses showed opposite expression of SPT and ALC orthologues between dry- and fleshy-fruited species during fruit maturation. Fleshy-fruited species turn off RPL and SPT orthologues during maturation. Conclusions: The gynoecium patterning and fruit developmental genetic network in the Brassicaceae cannot be directly extrapolated to the Solanaceae. In Solanaceae ALC, SPT and RPL contribute differently to maturation of dry dehiscent and fleshy fruits, whereas HEC genes are not generally expressed in the gynoecium. RPL genes have broader expression patterns than expected.


Assuntos
Flores/anatomia & histologia , Frutas/crescimento & desenvolvimento , Genes de Plantas/genética , Solanaceae/genética , Brassicaceae/genética , Brassicaceae/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/fisiologia , Phyllachorales , Reação em Cadeia da Polimerase , Homologia de Sequência , Solanaceae/anatomia & histologia , Solanaceae/crescimento & desenvolvimento
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