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1.
Plant Sci ; 313: 111072, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34763864

RESUMO

Necrotic and chlorotic symptoms induced during Pyrenophora teres infection in barley leaves indicate a compatible interaction that allows the hemi-biotrophic fungus Pyrenophora teres to colonise the host. However, it is unexplored how this fungus affects the physiological responses of resistant and susceptible cultivars during infection. To assess the degree of resistance in four different cultivars, we quantified visible symptoms and fungal DNA and performed expression analyses of genes involved in plant defence and ROS scavenging. To obtain insight into the interaction between fungus and host, we determined the activity of 19 key enzymes of carbohydrate and antioxidant metabolism. The pathogen impact was also phenotyped non-invasively by sensor-based multireflectance and -fluorescence imaging. Symptoms, regulation of stress-related genes and pathogen DNA content distinguished the cultivar Guld as being resistant. Severity of net blotch symptoms was also strongly correlated with the dynamics of enzyme activities already within the first day of infection. In contrast to the resistant cultivar, the three susceptible cultivars showed a higher reflectance over seven spectral bands and higher fluorescence intensities at specific excitation wavelengths. The combination of semi high-throughput physiological and molecular analyses with non-invasive phenotyping enabled the identification of bio-signatures that discriminates the resistant from susceptible cultivars.


Assuntos
Ascomicetos/patogenicidade , Resistência à Doença/genética , Suscetibilidade a Doenças , Hordeum/genética , Hordeum/microbiologia , Doenças das Plantas/microbiologia , Produtos Agrícolas/genética , Produtos Agrícolas/microbiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Fenótipo , Locos de Características Quantitativas
2.
Int J Mol Sci ; 22(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34638580

RESUMO

Wheat powdery mildew, caused by the obligate parasite Blumeria graminis f. sp. tritici, severely reduces wheat yields. Identifying durable and effective genes against wheat powdery mildew and further transferring them into wheat cultivars is important for finally controlling this disease in wheat production. Pm40 has been widely used in wheat breeding programs in Southwest China due to the spectrum and potentially durable resistance to powdery mildew. In the present study, a resistance test demonstrated that Pm40 is still effective against the Bgt race E20. We identified and cloned the TraesCS7B01G164000 with a total length of 4883 bp, including three exons and two introns, and encoded a protein carrying the CC-NBS-NBS-LRR domain in the Pm40-linked region flanked by two EST markers, BF478514 and BF291338, by integrating analysis of gene annotation in wheat reference genome and both sequence and expression difference in available transcriptome data. Two missense mutations were detected at positions 68 and 83 in the CC domain. The results of both cosegregation linkage analysis and qRT-PCR also suggested that TraesCS7B01G164000 was a potential candidate gene of Pm40. This study allowed us to move toward the final successfully clone and apply Pm40 in wheat resistance improvement by gene engineering.


Assuntos
Genes de Plantas/genética , Proteínas de Plantas/genética , Transcrição Genética/genética , Triticum/genética , Triticum/microbiologia , Ascomicetos/patogenicidade , China , Mapeamento Cromossômico/métodos , Clonagem Molecular/métodos , Resistência à Doença/genética , Éxons/genética , Ligação Genética/genética , Íntrons/genética , Melhoramento Vegetal/métodos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma/genética
3.
PLoS One ; 16(10): e0258043, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34653213

RESUMO

Fungal diseases in agronomically important plants such as grapevines result in significantly reduced production, pecuniary losses, and increased use of environmentally damaging chemicals. Beside the well-known diseases, there is an increased interest in wood-colonizing fungal pathogens that infect the woody tissues of grapevines. In 2015, a traditional isolation method was performed on grapevine trunks showing symptoms of trunk diseases in Hungary. One isolate (T15142) was identified as Kalmusia longispora (formerly Dendrothyrium longisporum) according to morphological and phylogenetic analyses. To evaluate the pathogenicity of this fungus on grapevines, artificial infections were carried out under greenhouse and field conditions, including the CBS 824.84 and ex-type CBS 582.83 strains. All isolates could be re-isolated from inoculated plants; however, varying virulence was observed among them in terms of the vascular necrosis caused. The incidence and severity of this symptom seemed to be congruent with the laccase-producing capabilities of the isolates. This is the first report on the ability of Kalmusia longispora to cause symptoms on grapevines, and on its possible dependence on laccase secretion.


Assuntos
Ascomicetos , Lacase/metabolismo , Doenças das Plantas/microbiologia , Vitis/microbiologia , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Virulência
4.
Plant Sci ; 311: 111009, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482912

RESUMO

Weeds, pests, and pathogens are among the pre-harvest constraints in rice farming across rice-growing countries. For weed management, manual weeding and herbicides are widely practiced. Among the herbicides, glyphosate [N-(phosphonomethyl) glycine] is a broad-spectrum systemic chemical extensively used in agriculture. Being a competitive structural analog to phosphoenolpyruvate, it selectively inhibits the conserved 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme required for the biosynthesis of aromatic amino acids and essential metabolites in eukaryotes and prokaryotes. In the present study, we investigated the antifungal and defense elicitor activity of glyphosate against Magnaporthe oryzae on transgenic-rice overexpressing a glyphosate-resistance OsEPSPS gene (T173I + P177S; TIPS OsmEPSPS) for blast disease management. The glyphosate foliar spray on OsmEPSPS transgenic rice lines showed both prophylactic and curative suppression of blast disease comparable to a blasticide, tricyclazole. The glyphosate displayed direct antifungal activity on Magnaporthe oryzae as well as enhanced the levels of antioxidant enzymes and photosynthetic pigments in rice. However, the genes associated with phytohormones-mediated defense (OsPAD4, OsNPR1.3, and OsFMO) and innate immunity pathway (OsCEBiP and OsCERK1) were found repressed upon glyphosate spray. Altogether, the current study is the first report highlighting the overexpression of a crop-specific TIPS mutation in conjugation with glyphosate application showing potential for blast disease management in rice cultivation.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/patogenicidade , Resistência a Herbicidas/genética , Herbicidas/farmacocinética , Oryza/genética , Oryza/microbiologia , Oryza/fisiologia , Doenças das Plantas/prevenção & controle , Ascomicetos/efeitos dos fármacos , Produtos Agrícolas/genética , Produtos Agrícolas/microbiologia , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Doenças das Plantas/genética , Plantas Geneticamente Modificadas/genética
5.
Appl Microbiol Biotechnol ; 105(19): 7395-7410, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34536105

RESUMO

In eukaryotes, myosin provides the necessary impetus for a series of physiological processes, including organelle movement, cytoplasmic flow, cell division, and mitosis. Previously, three members of myosin were identified in Magnaporthe oryzae, with class II and class V myosins playing important roles in intracellular transport, fungal growth, and pathogenicity. However, limited is known about the biological function of the class I myosin protein in the rice blast fungus. Here, we found that Momyo1 is highly expressed during conidiation and infection. Functional characterization of this gene via RNA interference (RNAi) revealed that Momyo1 is required for vegetative growth, conidiation, melanin pigmentation, and pathogenicity of M. oryzae. The Momyo1 knockdown mutant is defective in formation of appressorium-like structures (ALS) at the hyphal tips. In addition, Momyo1 also displays defects on cell wall integrity, hyphal hydrophobicity, extracellular enzyme activities, endocytosis, and formation of the Spitzenkörper. Furthermore, Momyo1 was identified to physically interact with the MoShe4, a She4p/Dim1p orthologue potentially involved in endocytosis, polarization of the actin cytoskeleton. Overall, our findings provide a novel insight into the regulatory mechanism of Momyo1 that is involved in fungal growth, cell wall integrity, endocytosis, and virulence of M. oryzae. KEY POINTS: • Momyo1 is required for vegetative growth and pigmentation of M. oryzae. • Momyo1 is essential for cell wall integrity and endocytosis of M. oryzae. • Momyo1 is involved in hyphal surface hydrophobicity of M. oryzae.


Assuntos
Ascomicetos/patogenicidade , Endocitose , Miosinas , Ascomicetos/crescimento & desenvolvimento , Miosinas/genética , Virulência
6.
PLoS One ; 16(9): e0257225, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506590

RESUMO

Diaporthe species are fungal plant pathogens of many important crops. Seed decay is one of the most important diseases on soybean. It is caused by various species of the genus Diaporthe and responsible for significant economic damage. In central Europe the four species D. longicolla, D. caulivora, D. eres, and D. novem are considered the principal species of Diaporthe on soybean. Fast and accurate detection of these pathogens is of utmost importance. In this study four species-specific TaqMan primer-probe sets that can be combined into a quadruplex assay were designed based on TEF sequences. The specificity and efficiency of the primer-probe sets were tested using PCR products and genomic DNA from pure cultures of the four Diaporthe species and other soybean fungal pathogens. Our results indicate that the primer-probe sets DPCL, DPCC, DPCE, and DPCN allow discrimination of D. longicolla, D. caulivora, D. eres, and D. novem, respectively, and can be used to detect and quantify these four Diaporthe species in parallel using quadruplex real-time PCR. In addition, the quadruplex real-time PCR assay was evaluated on different plant materials including healthy and infected soybean seeds or seed lots, soybean stems, and soybean leaves. This assay is a rapid and effective method to detect and quantify Diaporthe species from samples relevant for disease control.


Assuntos
Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Soja/microbiologia , Doenças das Plantas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Soja/metabolismo
7.
Elife ; 102021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528512

RESUMO

Genome evolution is driven by the activity of transposable elements (TEs). The spread of TEs can have deleterious effects including the destabilization of genome integrity and expansions. However, the precise triggers of genome expansions remain poorly understood because genome size evolution is typically investigated only among deeply divergent lineages. Here, we use a large population genomics dataset of 284 individuals from populations across the globe of Zymoseptoria tritici, a major fungal wheat pathogen. We built a robust map of genome-wide TE insertions and deletions to track a total of 2456 polymorphic loci within the species. We show that purifying selection substantially depressed TE frequencies in most populations, but some rare TEs have recently risen in frequency and likely confer benefits. We found that specific TE families have undergone a substantial genome-wide expansion from the pathogen's center of origin to more recently founded populations. The most dramatic increase in TE insertions occurred between a pair of North American populations collected in the same field at an interval of 25 years. We find that both genome-wide counts of TE insertions and genome size have increased with colonization bottlenecks. Hence, the demographic history likely played a major role in shaping genome evolution within the species. We show that both the activation of specific TEs and relaxed purifying selection underpin this incipient expansion of the genome. Our study establishes a model to recapitulate TE-driven genome evolution over deeper evolutionary timescales.


Assuntos
Ascomicetos/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Genoma Fúngico/genética , Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Triticum/microbiologia
8.
PLoS One ; 16(9): e0257863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591915

RESUMO

The endophytic bacterium Burkholderia contaminans NZ was isolated from jute, which is an important fiber-producing plant. This bacterium exhibits significant growth promotion activity in in vivo pot experiments, and like other plant growth-promoting (PGP) bacteria fixes nitrogen, produces indole acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. B. contaminans NZ is considered to exert a promising growth inhibitory effect on Macrophomina phaseolina, a phytopathogen responsible for infecting hundreds of crops worldwide. This study aimed to identify the possibility of B. contaminans NZ as a safe biocontrol agent and assess its effectiveness in suppressing phytopathogenic fungi, especially M. phaseolina. Co-culture of M. phaseolina with B. contaminans NZ on both solid and liquid media revealed appreciable growth suppression of M. phaseolina and its chromogenic aberration in liquid culture. Genome mining of B. contaminans NZ using NaPDoS and antiSMASH revealed gene clusters that displayed 100% similarity for cytotoxic and antifungal substances, such as pyrrolnitrin. GC-MS analysis of B. contaminans NZ culture extracts revealed various bioactive compounds, including catechol; 9,10-dihydro-12'-hydroxy-2'-methyl-5'-(phenylmethyl)- ergotaman 3',6',18-trione; 2,3-dihydro-3,5- dihydroxy-6-methyl-4H-pyran-4-one; 1-(1,6-Dioxooctadecyl)- pyrrolidine; 9-Octadecenamide; and 2- methoxy- phenol. These compounds reportedly exhibit tyrosinase inhibitory, antifungal, and antibiotic activities. Using a more targeted approach, an RP-HPLC purified fraction was analyzed by LC-MS, confirming the existence of pyrrolnitrin in the B. contaminans NZ extract. Secondary metabolites, such as catechol and ergotaman, have been predicted to inhibit melanin synthesis in M. phaseolina. Thus, B. contaminans NZ appears to inhibit phytopathogens by apparently impairing melanin synthesis and other potential biochemical pathways, exhibiting considerable fungistatic activity.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Burkholderia/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Melaninas/biossíntese , Pirrolnitrina/biossíntese , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Agentes de Controle Biológico/farmacologia , Burkholderia/metabolismo , Técnicas de Cocultura , Produtos Agrícolas/microbiologia , Endófitos , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Indolacéticos/metabolismo , Fixação de Nitrogênio , Pirrolnitrina/farmacologia , Sequenciamento Completo do Genoma
9.
BMC Plant Biol ; 21(1): 391, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418969

RESUMO

BACKGROUND: As effects of global climate change intensify, the interaction of biotic and abiotic stresses increasingly threatens current agricultural practices. The secondary cell wall is a vanguard of resistance to these stresses. Fusarium thapsinum (Fusarium stalk rot) and Macrophomina phaseolina (charcoal rot) cause internal damage to the stalks of the drought tolerant C4 grass, sorghum (Sorghum bicolor (L.) Moench), resulting in reduced transpiration, reduced photosynthesis, and increased lodging, severely reducing yields. Drought can magnify these losses. Two null alleles in monolignol biosynthesis of sorghum (brown midrib 6-ref, bmr6-ref; cinnamyl alcohol dehydrogenase, CAD; and bmr12-ref; caffeic acid O-methyltransferase, COMT) were used to investigate the interaction of water limitation with F. thapsinum or M. phaseolina infection. RESULTS: The bmr12 plants inoculated with either of these pathogens had increased levels of salicylic acid (SA) and jasmonic acid (JA) across both watering conditions and significantly reduced lesion sizes under water limitation compared to adequate watering, which suggested that drought may prime induction of pathogen resistance. RNA-Seq analysis revealed coexpressed genes associated with pathogen infection. The defense response included phytohormone signal transduction pathways, primary and secondary cell wall biosynthetic genes, and genes encoding components of the spliceosome and proteasome. CONCLUSION: Alterations in the composition of the secondary cell wall affect immunity by influencing phenolic composition and phytohormone signaling, leading to the action of defense pathways. Some of these pathways appear to be activated or enhanced by drought. Secondary metabolite biosynthesis and modification in SA and JA signal transduction may be involved in priming a stronger defense response in water-limited bmr12 plants.


Assuntos
Adaptação Fisiológica/genética , Secas , Lignina/biossíntese , Lignina/genética , Sorghum/química , Sorghum/genética , Sorghum/microbiologia , Ascomicetos/patogenicidade , Parede Celular/química , Parede Celular/genética , Grão Comestível/química , Grão Comestível/genética , Grão Comestível/microbiologia , Fusarium/patogenicidade , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Interações Hospedeiro-Patógeno/genética , Mutação , Transdução de Sinais , Estados Unidos , Água/metabolismo
10.
Biomolecules ; 11(8)2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34439811

RESUMO

Verticillium wilt, primarily induced by the soil-borne fungus Verticillium dahliae, is a serious threat to cotton fiber production. There are a large number of really interesting new gene (RING) domain-containing E3 ubiquitin ligases in Arabidopsis, of which three (At2g39720 (AtRHC2A), At3g46620 (AtRDUF1), and At5g59550 (AtRDUF2)) have a domain of unknown function (DUF) 1117 domain in their C-terminal regions. This study aimed to detect and characterize the RDUF members in cotton, to gain an insight into their roles in cotton's adaptation to environmental stressors. In this study, a total of 6, 7, 14, and 14 RDUF (RING-DUF1117) genes were detected in Gossypium arboretum, G. raimondii, G. hirsutum, and G. barbadense, respectively. These RDUF genes were classified into three groups. The genes in each group were highly conserved based on gene structure and domain analysis. Gene duplication analysis revealed that segmental duplication occurred during cotton evolution. Expression analysis revealed that the GhRDUF genes were widely expressed during cotton growth and under abiotic stresses. Many cis-elements related to hormone response and environment stressors were identified in GhRDUF promoters. The predicted target miRNAs and transcription factors implied that GhRDUFs might be regulated by gra-miR482c, as well as by transcription factors, including MYB, C2H2, and Dof. The GhRDUF genes responded to cold, drought, and salt stress and were sensitive to jasmonic acid, salicylic acid, and ethylene signals. Meanwhile, GhRDUF4D expression levels were enhanced after V. dahliae infection. Subsequently, GhRDUF4D was verified by overexpression in Arabidopsis and virus-induced gene silencing treatment in upland cotton. We observed that V. dahliae resistance was significantly enhanced in transgenic Arabidopsis, and weakened in GhRDUF4D silenced plants. This study conducted a comprehensive analysis of the RDUF genes in Gossypium, hereby providing basic information for further functional studies.


Assuntos
Proteínas de Arabidopsis/genética , Resistência à Doença/genética , Gossypium/genética , Doenças das Plantas/genética , Imunidade Vegetal/genética , Ubiquitina-Proteína Ligases/genética , Adaptação Fisiológica/genética , Adaptação Fisiológica/imunologia , Arabidopsis/classificação , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/metabolismo , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Sequência de Bases , Dedos de Zinco CYS2-HIS2/genética , Dedos de Zinco CYS2-HIS2/imunologia , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Gossypium/classificação , Gossypium/imunologia , Gossypium/microbiologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , MicroRNAs/genética , MicroRNAs/imunologia , Família Multigênica , Filogenia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Ubiquitina-Proteína Ligases/metabolismo
11.
Fungal Biol ; 125(9): 733-747, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420700

RESUMO

Genome sequence-driven molecular typing tools have the potential to uncover the population biology and genetic diversity of rapidly evolving plant pathogens like Magnaporthe oryzae. Here, we report a new molecular typing technique -a digitally portable tool for population genetic analysis of M. oryzae to decipher the genetic diversity. Our genotyping tool exploiting allelic variations in housekeeping and virulence genes coupled with pathotyping revealed a prevalence of genetically homogenous populations within a single-field and plant niches such as leaf and panicle. The M. oryzae inciting leaf-blast and panicle-blast were confirmed to be genetically identical with no or minor nucleotide polymorphism in 17 genomic loci analyzed. Genetic loci such as Mlc1, Mpg1, Mps1, Slp1, Cal, Ef-Tu, Pfk, and Pgk were highly polymorphic as indicated by the haplotype-diversity, the number of polymorphic sites, and the number of mutations. The genetically homogenous single field population showed high virulence variability or diversity on monogenic rice differentials. The study indicated that the genetic similarity displayed by the isolates collected from a particular geographical location had no consequence on their virulence pattern on rice differentials carrying single/multiple resistance genes. The data on virulence diversity showed by the identical Sequence Types (STs) is indicative of no congruence between polymorphic virulence genes-based pathotyping and conserved housekeeping genes-based genotyping.


Assuntos
Ascomicetos , Oryza , Ascomicetos/genética , Ascomicetos/patogenicidade , Genoma Fúngico/genética , Tipagem Molecular , Oryza/microbiologia , Doenças das Plantas/microbiologia , Virulência/genética
12.
Sci Rep ; 11(1): 15967, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354105

RESUMO

Barley production worldwide is limited by several abiotic and biotic stresses and breeding of highly productive and adapted varieties is key to overcome these challenges. Leaf scald, caused by Rhynchosporium commune is a major disease of barley that requires the identification of novel sources of resistance. In this study two subsets of genebank accessions were used: one extracted from the Reference set developed within the Generation Challenge Program (GCP) with 191 accessions, and the other with 101 accessions selected using the filtering approach of the Focused Identification of Germplasm Strategy (FIGS). These subsets were evaluated for resistance to scald at the seedling stage under controlled conditions using two Moroccan isolates, and at the adult plant stage in Ethiopia and Morocco. The results showed that both GCP and FIGS subsets were able to identify sources of resistance to leaf scald at both plant growth stages. In addition, the test of independence and goodness of fit showed that FIGS filtering approach was able to capture higher percentages of resistant accessions compared to GCP subset at the seedling stage against two Moroccan scald isolates, and at the adult plant stage against four field populations of Morocco and Ethiopia, with the exception of Holetta nursery 2017. Furthermore, four machine learning models were tuned on training sets to predict scald reactions on the test sets based on diverse metrics (accuracy, specificity, and Kappa). All models efficiently identified resistant accessions with specificities higher than 0.88 but showed different performances between isolates at the seedling and to field populations at the adult plant stage. The findings of our study will help in fine-tuning FIGS approach using machine learning for the selection of best-bet subsets for resistance to scald disease from the large number of genebank accessions.


Assuntos
Ascomicetos/patogenicidade , Resistência à Doença/genética , Hordeum/genética , Algoritmos , Ascomicetos/genética , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Bases de Dados Genéticas , Genes de Plantas/genética , Genótipo , Aprendizado de Máquina , Modelos Teóricos , Marrocos , Fenótipo , Melhoramento Vegetal/métodos , Doenças das Plantas , Folhas de Planta/genética , Locos de Características Quantitativas/genética , Plântula/genética
13.
Arch Microbiol ; 203(8): 5173-5182, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34338823

RESUMO

Endophytes associated with plants have the property to produce active biomolecules with their possible applications in agro-industrial sectors. This study provides a project work on analyzing various activities of fungal endophytes isolated from Swertia chirayita of Sikkim Himalayan region. Among several fungal endophytes screened, isolate UTCRF6 was found most active with the secretion of enzymes protease, cellulase, amylase and chitinase, as well as other metabolites Indoleacetic acid and siderophores. This endophyte was found active in restricting the growth of phyto-pathogens, including strains of Fusarium solani, Colletotrichum gloeosporioides, Alternaria alternata, Pestalotiopsis theae and Sclerotinia sclerotiorum. Morphological and molecular studies of this endophytic fungus showed similarity with Penicillium citrinum.


Assuntos
Ascomicetos , Agentes de Controle Biológico , Penicillium , Plantas Medicinais , Swertia , Alternaria/patogenicidade , Ascomicetos/patogenicidade , Colletotrichum/patogenicidade , Endófitos , Fusarium/patogenicidade , Plantas Medicinais/microbiologia , Swertia/microbiologia
14.
Cells ; 10(8)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34440713

RESUMO

Verticillium wilt, caused by the fungal pathogen Verticillium dahliae, is the most severe disease that threatens artichoke (Cynara scolymus L.) plants. Arbuscular mycorrhizal fungi (AMF) may represent a useful biological control strategy against this pathogen attack, replacing chemical compounds that, up to now, have been not very effective. In this study, we evaluated the effect of the AMF Glomus viscosum Nicolson in enhancing the plant tolerance towards the pathogen V. dahliae. The role of the ascorbate-glutathione (ASC-GSH) cycle and other antioxidant systems involved in the complex network of the pathogen-fungi-plant interaction have been investigated. The results obtained showed that the AMF G. viscosum is able to enhance the defense antioxidant systems in artichoke plants affected by V. dahliae, alleviating the oxidative stress symptoms. AMF-inoculated plants exhibited significant increases in ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), and superoxide dismutase (SOD) activities, a higher content of ascorbate (ASC) and glutathione (GSH), and a decrease in the levels of lipid peroxidation and hydrogen peroxide (H2O2). Hence, G. viscosum may represent an effective strategy for mitigating V. dahliae pathogenicity in artichokes, enhancing the plant defense systems, and improving the nutritional values and benefit to human health.


Assuntos
Antioxidantes/metabolismo , Ascomicetos/patogenicidade , Cynara scolymus/microbiologia , Fungos/fisiologia , Estresse Oxidativo , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/metabolismo , Ascorbato Peroxidases/metabolismo , Cynara scolymus/metabolismo , Interações Hospedeiro-Patógeno , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , NADH NADPH Oxirredutases/metabolismo , Doenças das Plantas/microbiologia , Superóxido Dismutase/metabolismo
15.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298948

RESUMO

Verticillium wilt, caused by Verticillium dahliae, is a devastating disease for many important crops, including cotton. Kiwellins (KWLs), a group of cysteine-rich proteins synthesized in many plants, have been shown to be involved in response to various phytopathogens. To evaluate genes for their function in resistance to Verticillium wilt, we investigated KWL homologs in cotton. Thirty-five KWL genes (GhKWLs) were identified from the genome of upland cotton (Gossypium hirsutum). Among them, GhKWL1 was shown to be localized in nucleus and cytosol, and its gene expression is induced by the infection of V. dahliae. We revealed that GhKWL1 was a positive regulator of GhERF105. Silencing of GhKWL1 resulted in a decrease, whereas overexpression led to an increase in resistance of transgenic plants to Verticillium wilt. Interestingly, through binding to GhKWL1, the pathogenic effector protein VdISC1 produced by V. dahliae could impair the defense response mediated by GhKWL1. Therefore, our study suggests there is a GhKWL1-mediated defense response in cotton, which can be hijacked by V. dahliae through the interaction of VdISC1 with GhKWL1.


Assuntos
Ascomicetos , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Gossypium , Doenças das Plantas , Fatores de Transcrição , Regulação para Cima , Fatores de Virulência , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Gossypium/genética , Gossypium/metabolismo , Gossypium/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Virulência/biossíntese , Fatores de Virulência/genética
16.
BMC Plant Biol ; 21(1): 357, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330216

RESUMO

BACKGROUND: Powdery mildew (PM), one of the major diseases in wheat, severely damages yield and quality, and the most economical and effective way to address this issue is to breed disease-resistant cultivars. Accordingly, 371 landraces and 266 released cultivars in Henan Province were genotyped by a 660 K microarray and phenotyped for adult plant resistance (APR) to PM from 2017 to 2020, and these datasets were used to conduct multilocus genome-wide association studies (GWASs). RESULTS: Thirty-six varieties showed stable APR in all the environments, and eleven quantitative trait nucleotides (QTNs) were found by multiple methods across multiple environments and best linear unbiased prediction (BLUP) values to be significantly associated with APR. Among these stable QTNs, four were previously reported, three were newly discovered in this study, and the others need to be further investigated. The major and newly discovered QTN, Qpm-3BL, was located at chr03BL_AX-109,052,670, while another newly discovered QTN, Qpm-1BL, was located between chr01BL_AX-108,771,002 and chr01BL_AX-110,117,322. Five and eight landraces were identified to be resistant based on Qpm-1BL (haplotype TC) and Qpm-3BL (allele T), respectively. To validate Qpm-3BL, a new kompetitive allele-specific PCR (KASP) marker was developed to scan 155 F2 individuals, and the average resistance score supported the value of Qpm-3BL in marker-assisted breeding. Near Qpm-3BL, PmBMYD was identified by KEGG, gene expression and comparative genomics analyses to be a candidate. Its resistance mechanism may involve gene tandem repeats. CONCLUSIONS: This study reveals a previously unknown gene for PM resistance that is available for marker-assisted breeding.


Assuntos
Ascomicetos/patogenicidade , Resistência à Doença/genética , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único , Triticum/genética , Triticum/microbiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Locos de Características Quantitativas
17.
Arch Virol ; 166(10): 2859-2863, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34291341

RESUMO

Sclerotinia sclerotiorum ourmiavirus 17 (SsOV17) was isolated from the hypovirulent strain GF3 of Sclerotinia sclerotiorum. The genome of SsOV17 is 2,802 nt in length and contains a single long open reading frame (ORF) flanked by a short structured 5'-untranslated region (5'-UTR) (28 nt) and a long 3'-UTR (788 nt), respectively. The ORF encodes a protein with 663 amino acids and a predicted molecular mass of 75.0 kDa. A BLASTp search indicated that the protein encoded by SsOV17 is closely related to the putative RNA-dependent RNA polymerase (RdRp) of Sclerotinia sclerotiorum ourmiavirus 13 (71% identity). A multiple sequence alignment indicated that eight conserved amino acid motifs were present in the RdRp conserved region of SsOV17. Phylogenetic analysis demonstrated that SsOV17 clustered with members of the genus Botoulivirus.


Assuntos
Ascomicetos/virologia , Micovírus/classificação , Doenças das Plantas/microbiologia , Vírus de RNA/classificação , Motivos de Aminoácidos , Ascomicetos/patogenicidade , Brassica napus/microbiologia , Micovírus/genética , Micovírus/isolamento & purificação , Genoma Viral/genética , Fases de Leitura Aberta/genética , Filogenia , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Regiões não Traduzidas/genética
18.
PLoS One ; 16(7): e0255029, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297754

RESUMO

Entomopathogenic fungi are regarded as effective biocontrol agents in pest management. Different fungi isolates exhibit varying degree of pathogenicity against red palm weevil [Rhynchophorus ferrugineus (Olivier)]. The pathogenicity of four native isolate from Saudi Arabia (three Beauveria bassiana named as BbSA-1, BbSA-2, BbSA-3 and one Metarhizium anisopliae regarded as MaSA-1) and three exotic isolates from Indonesia (B. bassiana coded as BbIDN-1 and M. anisopliae named as MaIDN-1 and MaIDN-2) was evaluated against red palm weevil under laboratory conditions. The isolates were applied to eggs (1 day old), larvae (3 and 35 days old), pupae (5 days old) and adults (10 days old). The average mortality rate of eggs and hatched larvae was 100% in all of the isolates except BbSA-2 and BbIDN-1, where mortality was 93.3 and 90%, respectively. The lowest mortality rate (73.3%) was recorded for BbSA-3 against 3-days-old larvae; however, all other isolates caused >80% larval mortality. Meanwhile, 93.3% mortality of 35-day-old larvae was noted for MaSA-1 isolate. The highest pupa mortality (80%) was observed for MaSA-1, while remaining isolates caused >60% mortality. The isolates BbSA-1 and MaSA-1 caused 61 and 74.3% mortality in adults, respectively. The tested fungi isolates exhibited high virulence against all life stages of red palm weevil. Local isolates had higher pathogenicity than exotic isolates. The findings of the current study suggest that entomopathogenic fungi could be used as biological control agents for the management of red palm weevil. However, field studies are needed to reach the sound conclusions and practical applications.


Assuntos
Ascomicetos/patogenicidade , Besouros/microbiologia , Controle Biológico de Vetores/métodos , Animais , Besouros/crescimento & desenvolvimento , Larva/microbiologia , Pupa/microbiologia
19.
Plant Cell Rep ; 40(10): 1799-1812, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34232377

RESUMO

Charcoal rot (CR) is a major disease of soybean, which is caused by Macrophomina phaseolina (Mp). Increasing temperatures and low rainfall in recent years have immensely benefitted the pathogen. Hence, the search for genetically acquired resistance to this pathogen is essential. The pathogen is a hemibiotroph, which germinates on the root surface and colonizes epidermal tissue. Several surface receptors initiate pathogenesis, followed by the secretion of various enzymes that provide entry to host tissue. Several enzymes and other converging cascades in the pathogen participate against host defensive responses. ß-glucan of the fungal cell wall is recognized as MAMPs (microbe-associated molecular patterns) in plants, which trigger host immune responses. Kinase receptors, resistance, and pathogenesis-related genes correspond to host defense response. They work in conjunction with hormone-mediated defense pathway especially, the systemic acquired resistance, calcium-signaling, and production of phytoalexins. Due to its quantitative nature, limited QTLs have been identified in soybean for CR resistance. The present review attempts to provide a functional link between M. phaseolina pathogenicity and soybean responses. Elucidation of CR resistance responses would facilitate improved designing of breeding programs, and may help in the selection of corresponding genes to introgress CR resistant traits.


Assuntos
Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Soja/genética , Soja/microbiologia , Sinalização do Cálcio , Resistência à Doença/genética , Interações Hospedeiro-Patógeno/fisiologia , Doenças das Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas
20.
Sci Rep ; 11(1): 14098, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34239007

RESUMO

Grapevine trunk diseases (GTDs) are well-known and significant fungal diseases of Vitis vinifera with a worldwide distribution. During August to November 2016 in a survey to characterize fungi associated with grapevine trunk diseases in Kermanshah Province (west of Iran) vineyards, 286 fungal isolates were obtained. Based on morphology and DNA sequences data eight species were identified, of which Biscogniauxia rosacearum, Neoscytalidium hyalinum and Phaeoacremonium minimum were the most aggressive fungal pathogenic species characterized in this research. N. hyalinum was the most prevalent species. N. hyalinum and Ph. minimum have previously been reported from Vitis vinifera. Thus far, there are two records of Biscogniauxia mediterranea and Biscogniauxia capnodes on grapevine in the world with no data on pathology aspects. To our knowledge, it is the first time B. rosacearum is reported from grapevine across the globe. Pathogenicity test with three strains of B. rosacearum on 2-year-old potted grapevines confirmed the pathogenicity of B. rosacearum on grapevine. The proximity of vineyards to the oak trees in Zagros forests as one of the plant hosts of Biscogniauxia spp. further highlights the need for extensive studies on B. rosacearum as a new fungal pathogen.


Assuntos
Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Vitis/microbiologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , DNA Intergênico/genética , Geografia , Irã (Geográfico) , Filogenia
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