Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 21.103
Filter
1.
Plant Mol Biol ; 114(5): 105, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39316277

ABSTRACT

MicroRNAs (miRNAs) are short, non-coding RNAs that regulate gene expression at the post-transcriptional level. In plants, miRNAs participate in diverse developmental processes and adaptive responses to biotic and abiotic stress. MiR827 has long been recognized to be involved in plant responses to phosphate starvation. In rice, the miR827 regulates the expression of OsSPX-MFS1 and OsSPX-MFS2, these genes encoding vacuolar phosphate transporters. In this study, we demonstrated that miR827 plays a role in resistance to infection by the fungus Magnaporthe oryzae in rice. We show that MIR827 overexpression enhances susceptibility to infection by M. oryzae which is associated to a weaker induction of defense gene expression during pathogen infection. Conversely, CRISPR/Cas9-induced mutations in the MIR827 gene completely abolish miR827 production and confer resistance to M. oryzae infection. This resistance is accompanied by a reduction of leaf Pi content compared to wild-type plants, whereas Pi levels increase in leaves of the blast-susceptible miR827 overexpressor plants. In wild-type plants, miR827 accumulation in leaves decreases during the biotrophic phase of the infection process. Taken together, our data indicates that silencing MIR827 confers resistance to M. oryzae infection in rice while further supporting interconnections between Pi signaling and immune signaling in plants. Unravelling the role of miR827 during M. oryzae infection provides knowledge to improve blast resistance in rice by CRISPR/Cas9-editing of MIR827.


Subject(s)
CRISPR-Cas Systems , Disease Resistance , Gene Expression Regulation, Plant , MicroRNAs , Oryza , Plant Diseases , Oryza/microbiology , Oryza/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Plant Diseases/microbiology , Plant Diseases/genetics , Disease Resistance/genetics , Plants, Genetically Modified , Gene Silencing , Plant Leaves/microbiology , Plant Leaves/genetics , Ascomycota/physiology , Ascomycota/pathogenicity , Magnaporthe/physiology , Plant Proteins/genetics , Plant Proteins/metabolism
2.
BMC Microbiol ; 24(1): 356, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39300361

ABSTRACT

BACKGROUND: Maple is an important ornamental plant in China. With the increasing use of maple trees in landscaping, a symptom of shoot dieback has been observed in Henan province, China. RESULTS: In this study, 28 Diaporthe isolates were obtained from symptomatic shoots of maple trees between 2020 and 2023. Phylogenetic analyses based on five loci (ITS, TEF, CAL, HIS and TUB) coupled with morphology of 12 representative isolates identified three known species (D. eres, D. pescicola and D. spinosa) and one new species, namely D. pseudoacerina sp. nov. Koch's postulates confirmed that all these species were pathogenic. Additionally, D. pseudoacerina was able to infect China wingnut (Pterocarya stenoptera), pear (Pyrus sp.), and black locust (Robinia pseudoacacia). This study marks the first report of Diaporthe spinosa and D. pescicola pathogens infecting maple trees. CONCLUSIONS: These findings enhance the existing knowledge of the taxonomy and host diversity of Diaporthe species as, while also providing valuable information for managing of maple shoot dieback in Henan Province, China.


Subject(s)
Acer , Ascomycota , Phylogeny , Plant Diseases , Plant Shoots , Acer/microbiology , China , Plant Diseases/microbiology , Plant Shoots/microbiology , Ascomycota/genetics , Ascomycota/classification , Ascomycota/isolation & purification , Ascomycota/physiology , DNA, Fungal/genetics , Sequence Analysis, DNA , Pyrus/microbiology
3.
J Appl Microbiol ; 135(9)2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39289002

ABSTRACT

AIMS: The immense therapeutic value of Valeriana jatamansi is attributed to the presence of bioactive secondary metabolites (valepotriates and sesquiterpenoids). Its over-exploitation in wild habitats resulted in extensive depletion, necessitating alternative approaches to produce its therapeutic metabolites. This study sought to assess the ability of endophytes of V. jatamansi to boost the biosynthesis of secondary metabolites in the leaf-cell suspension (LCS) culture of V. jatamansi. METHODS AND RESULTS: A total of 11 fungal endophytes were isolated from the rhizomes of V. jatamansi. Isolated endophytes were found to belong to phylum Ascomycota, Basidiomycota, and Mucoromycota. Supplementation of extracts of endophyte Phaeosphaeriaceae sp. VRzFB, Mucor griseocyanus VRzFD, Penicillium raistrickii VRzFK, and Penicillium sajarovii VRzFL in the LCS culture of V. jatamansi increased the fresh cell biomass by 19.6%-39.1% and dry cell biomass by 23.4%-37.8%. Most of the endophytes' extract could increase the content of valepotriates (26.5%-76.5% valtrate and 40.5%-77.9% acevaltrate) and sesquiterpenoids (19.9%-61.1% hydroxyl valerenic acid) in LCS culture. However, only two endophytes, Irpex lacteus VRzFI and Fusarium oxysporum VRzFF, could increase the sesquiterpenoids acetoxy valerenic acid (36.9%-55.3%). In contrast, some endophytes' extracts caused negative or no significant effect on the cell biomass and targeted metabolites. Increased secondary metabolites were corroborated with increased expression of iridoid biosynthesis genes in LCS culture. Production of H2O2 and lipid peroxidation was also varied with different endophytes indicating the modulation of cellular oxidative stress due to endophyte elicitors. CONCLUSIONS: The results suggest the distinct effect of different fungal endophytes-extract on LCS culture, and endophytes can serve as biotic elicitors for increasing the secondary metabolite production in plant in vitro systems.


Subject(s)
Endophytes , Plant Leaves , Sesquiterpenes , Valerian , Endophytes/metabolism , Sesquiterpenes/metabolism , Valerian/microbiology , Valerian/metabolism , Plant Leaves/microbiology , Fungi/metabolism , Ascomycota/metabolism , Rhizome/microbiology , Penicillium/metabolism , Secondary Metabolism
4.
PLoS Pathog ; 20(9): e1012536, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39312592

ABSTRACT

The regulation of virulence in plant-pathogenic fungi has emerged as a key area of importance underlying host infections. Recent work has highlighted individual transcription factors (TFs) that serve important roles. A prominent example is PnPf2, a member of the Zn2Cys6 family of fungal TFs, which controls the expression of effectors and other virulence-associated genes in Parastagonospora nodorum during infection of wheat. PnPf2 orthologues are similarly important for other major fungal pathogens during infection of their respective host plants, and have also been shown to control polysaccharide metabolism in model saprophytes. In each case, the direct genomic targets and associated regulatory mechanisms were unknown. Significant insight was made here by investigating PnPf2 through chromatin-immunoprecipitation (ChIP) and mutagenesis approaches in P. nodorum. Two distinct binding motifs were characterised as positive regulatory elements and direct PnPf2 targets identified. These encompass known effectors and other components associated with the P. nodorum pathogenic lifestyle, such as carbohydrate-active enzymes and nutrient assimilators. The results support a direct involvement of PnPf2 in coordinating virulence on wheat. Other prominent PnPf2 targets included TF-encoding genes. While novel functions were observed for the TFs PnPro1, PnAda1, PnEbr1 and the carbon-catabolite repressor PnCreA, our investigation upheld PnPf2 as the predominant transcriptional regulator characterised in terms of direct and specific coordination of virulence on wheat, and provides important mechanistic insights that may be conserved for homologous TFs in other fungi.


Subject(s)
Ascomycota , Fungal Proteins , Gene Expression Regulation, Fungal , Plant Diseases , Transcription Factors , Triticum , Triticum/microbiology , Plant Diseases/microbiology , Transcription Factors/metabolism , Transcription Factors/genetics , Virulence , Fungal Proteins/metabolism , Fungal Proteins/genetics , Ascomycota/pathogenicity , Ascomycota/genetics , Ascomycota/metabolism
5.
Mol Plant Pathol ; 25(9): e13498, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39305021

ABSTRACT

We examined the molecular basis of triazole resistance in Blumeria graminis f. sp. tritici (wheat mildew, Bgt), a model organism among powdery mildews. Four genetic models for responses to triazole fungicides were identified among US and UK isolates, involving multiple genetic mechanisms. Firstly, only two amino acid substitutions in CYP51B lanosterol demethylase, the target of triazoles, were associated with resistance, Y136F and S509T (homologous to Y137F and S524T in the reference fungus Zymoseptoria tritici). As sequence variation did not explain the wide range of resistance, we also investigated Cyp51B copy number and expression, the latter using both reverse transcription-quantitative PCR and RNA-seq. The second model for resistance involved higher copy number and expression in isolates with a resistance allele; thirdly, however, moderate resistance was associated with higher copy number of wild-type Cyp51B in some US isolates. A fourth mechanism was heteroallelism with multiple alleles of Cyp51B. UK isolates, with significantly higher mean resistance than their US counterparts, had higher mean copy number, a high frequency of the S509T substitution, which was absent from the United States, and in the most resistant isolates, heteroallelism involving both sensitivity residues Y136+S509 and resistance residues F136+T509. Some US isolates were heteroallelic for Y136+S509 and F136+S509, but this was not associated with higher resistance. The obligate biotrophy of Bgt may constrain the tertiary structure and thus the sequence of CYP51B, so other variation that increases resistance may have a selective advantage. We describe a process by which heteroallelism may be adaptive when Bgt is intermittently exposed to triazoles.


Subject(s)
Ascomycota , Drug Resistance, Fungal , Fungicides, Industrial , Gene Dosage , Drug Resistance, Fungal/genetics , Ascomycota/drug effects , Ascomycota/genetics , Fungicides, Industrial/pharmacology , Fungal Proteins/genetics , Fungal Proteins/metabolism , Triazoles/pharmacology , Plant Diseases/microbiology , Triticum/microbiology , Triticum/genetics , Gene Expression Regulation, Fungal/drug effects , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Sterol 14-Demethylase/genetics , Sterol 14-Demethylase/metabolism
6.
J Agric Food Chem ; 72(38): 20892-20904, 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39255954

ABSTRACT

Apple ring rot, caused by the pathogenic fungus Botryosphaeria dothidea, has inflicted substantial economic losses and caused significant food safety concerns. In this study, a pimarane-type diterpenoid, diaporthein B (DTB), isolated from a marine-derived fungus, exhibited significant antifungal activity against B. dothidea, with an EC50 value of 8.8 µg/mL. Transcriptome, metabolome, and physiological assays revealed that DTB may target mitochondria and disrupt the tricarboxylic acid (TCA) cycle and oxidative phosphorylation processes. This interference led to increased accumulation of reactive oxygen species and subsequent lipid peroxidation, ultimately inhibiting fungal growth. Furthermore, DTB exhibited an inhibitory potency against apple ring rot at a concentration of 31.2 µg/mL, achieving rates ranging from 67.7 to 81.6% across four distinct apple cultivars. These results indicated that DTB could serve as a novel fungicide for controlling apple ring rot in apple cultivation, transportation, and storage.


Subject(s)
Ascomycota , Fungicides, Industrial , Malus , Plant Diseases , Malus/microbiology , Malus/chemistry , Plant Diseases/microbiology , Plant Diseases/prevention & control , Ascomycota/drug effects , Fungicides, Industrial/pharmacology , Fungicides, Industrial/chemistry , Diterpenes/pharmacology , Diterpenes/chemistry , Fruit/microbiology , Fruit/chemistry
7.
J Agric Food Chem ; 72(38): 20882-20891, 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39262056

ABSTRACT

Naturally derived compounds show promise as treatments for microbial infections. Polyphenols, abundantly found in various plants, fruits, and vegetables, are noted for their physiological benefits including antimicrobial effects. This study introduced a new set of acylated phloroglucinol derivatives, synthesized and tested for their antifungal activity in vitro against seven different pathogenic fungi. The standout compound, 3-methyl-1-(2,4,6-trihydroxyphenyl) butan-1-one (2b), exhibited remarkable fungicidal strength, with EC50 values of 1.39 µg/mL against Botrytis cinerea and 1.18 µg/mL against Monilinia fructicola, outperforming previously screened phenolic compounds. When tested in vivo, 2b demonstrated effective antifungal properties, with cure rates of 76.26% for brown rot and 83.35% for gray mold at a concentration of 200 µg/mL, rivaling the commercial fungicide Pyrimethanil in its efficacy against B. cinerea. Preliminary research suggests that 2b's antifungal mechanism may involve the disruption of spore germination, damage to the fungal cell membrane, and leakage of cellular contents. These results indicate that compound 2b has excellent fungicidal properties against B. cinerea and holds potential as a treatment for gray mold.


Subject(s)
Ascomycota , Botrytis , Fungicides, Industrial , Phloroglucinol , Plant Diseases , Botrytis/drug effects , Botrytis/growth & development , Phloroglucinol/pharmacology , Phloroglucinol/chemistry , Fungicides, Industrial/pharmacology , Fungicides, Industrial/chemistry , Ascomycota/drug effects , Plant Diseases/microbiology , Microbial Sensitivity Tests
8.
Sci Rep ; 14(1): 21813, 2024 09 18.
Article in English | MEDLINE | ID: mdl-39294226

ABSTRACT

Rice (Oryza sativa) is a staple food for billions of people across the globe, that feeds nearly three-quarters of the human population on Earth, particularly in Asian countries. Rice yield has been drastically reduced and severely affected by various biotic and abiotic stresses, especially pathogens. Controlling the attack of such pathogens is a matter of immediate concern as yield losses in rice crops could deprive millions of lives of nourishment worldwide. Pyricularia oryzae is one such pathogen that has been considered the major disease of rice because of its worldwide geographic distribution. P. oryzae belongs to the kingdom fungi, that causes rice blast ultimately adversely affecting the yield of the rice crop. Keeping in view this alarming scenario, the present study was designed so that the identifications of genome-encoded miRNAs of Oryza sativa were employed to target and silence the genome of P. oryzae. This study accomplished the computational analysis of algorithms related to miRNA target prediction. Four computational target prediction algorithms i.e., psRNATarget, RNA22, miRanda, and RNAhybrid were utilized in this investigation. The consensus among target prediction algorithms was created to discover six miRNAs from the O. sativa genome with the conservation of the target site fully evaluated on the genome of P. oryzae. The discovery of these novel six miRNAs in Oryza sativa paved a strong way toward the control of this disease in rice. It will open doors for further research in the field of gene silencing in rice. These miRNAs can be designed and employed in the future as experimentation to create constructs regarding the silencing of P. oryzae in rice crops. In the future, this research would be surely helpful for the development of P. oryzae resistant rice varieties.


Subject(s)
Ascomycota , MicroRNAs , Oryza , Plant Diseases , Oryza/genetics , Oryza/microbiology , MicroRNAs/genetics , Plant Diseases/microbiology , Plant Diseases/genetics , Ascomycota/genetics , Ascomycota/pathogenicity , Genome, Fungal , Genome, Plant , Computational Biology/methods , Algorithms
9.
J Org Chem ; 89(18): 13359-13366, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39239664

ABSTRACT

Indole alkaloids are privileged secondary metabolites, and their production may be achieved by the microbial biotransformation of tryptophan analogues. By feeding 1-methyl-L-tryptophan (1-MT) into the culture of endophytic Nigrospora chinensis GGY-3, six novel (1-6) and seven known indole alkaloids (7-13) were generated. Their structures were elucidated by means of NMR spectroscopy, experimental electronic circular dichroism (ECD) spectra, and X-ray crystallography analysis. A Friedel-Crafts reaction was proposed as the key reaction responsible for the formation of the new compounds. Racemates 4 and 6 were separated into isomers by chiral HPLC, with their absolute configurations determined by X-ray and ECD calculation. Compounds 3, 4, and 8 display good herbicidal activity against dicotyledon weed Eclipta prostrata, of which 4 and 8 exhibited 88.50% and 100% inhibition rates on the radicle at 200 µg/mL, respectively, a similar effect compared to the positive control penoxsulam.


Subject(s)
Biotransformation , Herbicides , Indole Alkaloids , Tryptophan , Indole Alkaloids/chemistry , Indole Alkaloids/pharmacology , Indole Alkaloids/metabolism , Indole Alkaloids/isolation & purification , Tryptophan/chemistry , Tryptophan/metabolism , Herbicides/chemistry , Herbicides/pharmacology , Herbicides/metabolism , Ascomycota/chemistry , Ascomycota/metabolism , Molecular Structure , Crystallography, X-Ray , Models, Molecular , Molecular Conformation
10.
BMC Plant Biol ; 24(1): 846, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39251916

ABSTRACT

BACKGROUND: Septoria tritici blotch (STB) disease causes yield losses of up to 50 per cent in susceptible wheat cultivars and can reduce wheat production. In this study, genomic architecture for adult-plant STB resistance in a Septoria Association Mapping Panel (SAMP) having 181 accessions and genomic regions governing STB resistance in a South Asian wheat panel were looked for. RESULTS: Field experiments during the period from 2019 to 2021 revealed those certain accessions, namely BGD52 (CHIR7/ANB//CHIR1), BGD54 (CHIR7/ANB//CHIR1), IND92 (WH 1218), IND8 (DBW 168), and IND75 (PBW 800), exhibited a high level of resistance. Genetic analysis revealed the presence of 21 stable quantitative trait nucleotides (QTNs) associated with resistance to STB (Septoria tritici blotch) on all wheat chromosomes, except for 2D, 3A, 3D, 4A, 4D, 5D, 6B, 6D, and 7A. These QTNs were predominantly located in chromosome regions previously identified as associated with STB resistance. Three Quantitative Trait Loci (QTNs) were found to have significant phenotypic effects in field evaluations. These QTNs are Q.STB.5A.1, Q.STB.5B.1, and Q.STB.5B.3. Furthermore, it is possible that the QTNs located on chromosomes 1A (Q.STB.1A.1), 2A (Q.STB_DH.2A.1, Q.STB.2A.3), 2B (Q.STB.2B.4), 5A (Q.STB.5A.1, Q.STB.5A.2), and 7B (Q.STB.7B.2) could potentially be new genetic regions associated with resistance. CONCLUSION: Our findings demonstrate the importance of Asian bread wheat as a source of STB resistance alleles and novel stable QTNs for wheat breeding programs aiming to develop long-lasting and wide-ranging resistance to Zymoseptoria tritici in wheat cultivars.


Subject(s)
Ascomycota , Disease Resistance , Genome-Wide Association Study , Plant Diseases , Quantitative Trait Loci , Triticum , Triticum/genetics , Triticum/microbiology , Triticum/immunology , Plant Diseases/microbiology , Plant Diseases/genetics , Plant Diseases/immunology , Disease Resistance/genetics , Ascomycota/physiology , Chromosome Mapping , Chromosomes, Plant/genetics
11.
Virulence ; 15(1): 2401978, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39263889

ABSTRACT

Mycoviruses can alter the biological characteristics of host fungi, including change virulence or pathogenicity of phytopathogens and entomopathogenic fungi (EPF). However, most studies on the mycoviruses found in EPF have focused on the effects of the viruses on the virulence of host fungi towards insect pests, with relatively few reports on the effects to the host fungi with regard to plant disease resistance in hosts. The present study investigated the effects of the mycovirus Beauveria bassiana chrysovirus 2 (BbCV2) virus infection on host biological characteristics, evaluated antagonistic activity of BbCV2 against two phytopathogenic fungi (Sclerotinia sclerotiorum and Botrytis cinerea), and transcriptome analysis was used to reveal the interactions between viruses and hosts. Our results showed that BbCV2 virus infection increased B. bassiana's growth rate, spore production, and biomass, it also enhanced the capacity of host fungi and their metabolic products to inhibit phytopathogenic fungi. BbCV2 virus infection reduced the contents of the two pathogens in tomato plants significantly, and transcriptome analysis revealed that the genes related to competition for ecological niches and nutrition, mycoparasitism and secondary metabolites in B. bassiana were significantly up-regulated after viral infection. These findings indicated that the mycovirus infection is an important factor to enhance the ability of B. bassiana against plant disease after endophytic colonization. We suggest that mycovirus infection causes a positive effect on B. bassiana against phytopathogens, which should be considered as a potential strategy to promote the plant disease resistance of EPF.


Subject(s)
Botrytis , Disease Resistance , Fungal Viruses , Plant Diseases , Solanum lycopersicum , Fungal Viruses/physiology , Fungal Viruses/genetics , Plant Diseases/microbiology , Botrytis/pathogenicity , Botrytis/virology , Animals , Solanum lycopersicum/microbiology , Solanum lycopersicum/virology , Ascomycota/virology , Ascomycota/pathogenicity , Ascomycota/genetics , Virulence , Insecta/microbiology , Insecta/virology , Beauveria/pathogenicity , Beauveria/genetics , Beauveria/physiology , Gene Expression Profiling
12.
Virulence ; 15(1): 2403566, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39285518

ABSTRACT

The filamentous fungus Magnaporthe oryzae is widely recognized as a notorious plant pathogen responsible for causing rice blasts. With rapid advancements in molecular biology technologies, numerous regulatory mechanisms have been thoroughly investigated. However, most recent studies have predominantly focused on infection-related pathways or host defence mechanisms, which may be insufficient for developing novel structure-based prevention strategies. A substantial body of literature has utilized cryo-electron microscopy and X-ray diffraction to explore the relationships between functional components, shedding light on the identification of potential drug targets. Owing to the complexity of protein extraction and stochastic nature of crystallization, obtaining high-quality structures remains a significant challenge for the scientific community. Emerging computational tools such as AlphaFold for structural prediction, docking for interaction analysis, and molecular dynamics simulations to replicate in vivo conditions provide novel avenues for overcoming these challenges. In this review, we aim to consolidate the structural biological advancements in M. oryzae, drawing upon mature experimental experiences from other species such as Saccharomyces cerevisiae and mammals. We aim to explore the potential of protein construction to address the invasion and proliferation of M. oryzae, with the goal of identifying new drug targets and designing small-molecule compounds to manage this disease.


Subject(s)
Fungal Proteins , Oryza , Plant Diseases , Oryza/microbiology , Plant Diseases/microbiology , Fungal Proteins/chemistry , Fungal Proteins/genetics , Fungal Proteins/metabolism , Ascomycota/genetics , Ascomycota/pathogenicity , Ascomycota/chemistry , Cryoelectron Microscopy
13.
An Acad Bras Cienc ; 96(suppl 1): e20230251, 2024.
Article in English | MEDLINE | ID: mdl-39292101

ABSTRACT

The diversity of endophytes and their ecological relationships with the endangered conifer Araucaria angustifolia (a critically endangered species) are unrevealed. This study aimed to characterize the diversity of endophytic fungi associated with A. angustifolia. To this end, we analyzed 90 fragments from five individuals collected from a mixed localized fragment in Guarapuava-PR, Brazil. The total DNA of 61 morphotypes was extracted and the Internal Transcribed Spacer (ITS) region was amplified and sequenced. The sequence analysis allowed the identification of 37 genera belonging to the phylum Ascomycota and the classes Eurotiomycetes, Dothideomycetes, and Sordariomycetes, divided into 11 orders and 13 families. Most of the isolated fungi belonged to the Sordariomycetes class (40%) and to the Xylaria genus (14%), while Eurotiomycetes was the minority class within the community. Our results reveal the high endophytic richness supporting the life cycle of A. angustifolia and reinforce the necessity for the conservation of this conifer, as many genetic resources can be lost owing to its irrational exploration.


Subject(s)
Araucaria , Endophytes , Endophytes/classification , Endophytes/genetics , Endophytes/isolation & purification , Brazil , Araucaria/microbiology , DNA, Fungal/genetics , Biodiversity , Ascomycota/classification , Ascomycota/isolation & purification , Ascomycota/genetics , Phylogeny , Fungi/classification , Fungi/isolation & purification , Fungi/genetics , Sequence Analysis, DNA
14.
Pestic Biochem Physiol ; 204: 106028, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39277356

ABSTRACT

The destructive disease gray leaf spot, caused by Stemphylium solani, is prevalent in tomato plants in China. A variety of fungicides have been extensively used for controlling the disease, with a particular focus on succinate dehydrogenase inhibitors (SDHIs) and quinone outside inhibitors (QoIs). However, there was a lack of information regarding the resistance of S. solani to boscalid (SDHI) and pyraclostrobin (QoI) in China. In this study, the sensitivity of S. solani to boscalid and pyraclostrobin was monitored. The EC50 values for boscalid ranged from 0.02 to 3.0 µg∙mL-1, with an average value of 0.62 µg∙mL-1, while the EC50 values for pyraclostrobin ranged from 0.21 to 14.71 µg∙mL-1, with an average value of 6.03 µg∙mL-1. Based on these findings, the frequencies of observed resistance were as follows: 36.7% for boscalid and 50% for pyraclostrobin; while the resistance frequency to both boscalid and pyraclostrobin in S. solani was 19.4%. The mutation associated with boscalid resistance in S. solani within tomato fields was identified as SdhB-H277Y, while the mutation related to pyraclostrobin resistance was found in cytochrome b, specifically Cytb-G143A. The resistant mutants displayed diminished fitness in terms of mycelial growth, yet their pathogenicity exhibited no significant disparities. To delay the development of resistance, it is advisable to employ a rotation strategy using alternative fungicides with different modes of action or mix with fungicides with multi-site-contact activity for disease management.


Subject(s)
Ascomycota , Biphenyl Compounds , Drug Resistance, Fungal , Fungicides, Industrial , Niacinamide , Plant Diseases , Solanum lycopersicum , Strobilurins , Strobilurins/pharmacology , Solanum lycopersicum/microbiology , Fungicides, Industrial/pharmacology , Plant Diseases/microbiology , Niacinamide/pharmacology , Niacinamide/analogs & derivatives , Drug Resistance, Fungal/genetics , China , Biphenyl Compounds/pharmacology , Ascomycota/drug effects , Ascomycota/pathogenicity
15.
Pestic Biochem Physiol ; 204: 106095, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39277406

ABSTRACT

Plant growth-promoting rhizobacteria (PGPR) have been reported to suppress various diseases as potential bioagents. It can inhibit disease occurrence through various means such as directly killing pathogens and inducing systemic plant resistance. In this study, a bacterium isolated from soil showed significant inhibition of Valsa mali. Morphological observations and phylogenetic analysis identified the strain as Pseudomonas thivervalensis, named K321. Plate confrontation assays demonstrated that K321 treatment severely damaged V. mali growth, with scanning electron microscopy (SEM) observations showing severe distortion of hyphae due to K321 treatment. In vitro twigs inoculation experiments indicated that K321 had good preventive and therapeutic effects against apple Valsa canker (AVC). Applying K321 on apples significantly enhanced the apple inducing systemic resistance (ISR), including induced expression of apple ISR-related genes and increased ISR-related enzyme activity. Additionally, applying K321 on apples can activate apple MAPK by enhancing the phosphorylation of MPK3 and MPK6. In addition, K321 can promote plant growth by solubilizing phosphate, producing siderophores, and producing 3-indole-acetic acid (IAA). Application of 0.2% K321 increased tomato plant height by 53.71%, while 0.1% K321 increased tomato fresh weight by 59.55%. Transcriptome analysis revealed that K321 can inhibit the growth of V. mali by disrupting the integrity of its cell membrane through inhibiting the metabolism of essential membrane components (fatty acids) and disrupting carbohydrate metabolism. In addition, transcriptome analysis also showed that K321 can enhance plant resistance to AVC by inducing ISR-related hormones and MAPK signaling, and application of K321 significantly induced the transcription of plant growth-related genes. In summary, an excellent biocontrol strain has been discovered that can prevent AVC by inducing apple ISR and directly killing V. mali. This study indicated the great potential of P. thivervalensis K321 for use as a biological agent for the control of AVC.


Subject(s)
Malus , Plant Diseases , Pseudomonas , Malus/microbiology , Plant Diseases/prevention & control , Plant Diseases/microbiology , Pseudomonas/physiology , Ascomycota/physiology , Biological Control Agents , Disease Resistance
16.
BMC Microbiol ; 24(1): 343, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39271969

ABSTRACT

BACKGROUND: Poplar canker caused by Botryosphaeria dothidea is one of the most severe plant disease of poplars worldwide. In our study, we aimed to investigate the modes of antagonism by fermentation broth supernatant (FBS) of Streptomyces spiroverticillatus HS1 against B. dothidea. RESULTS: In vitro, the strain and FBS of S. spiroverticillatus HS1 significantly inhibited mycelial growth and biomass accumulation, and also disrupted the mycelium morphology of B. dothidea. On the 3rd day after treatment, the inhibition rates of colony growth and dry weight were 80.72% and 52.53%, respectively. In addition, FBS treatment damaged the plasma membrane of B. dothidea based on increased electrical conductivity in the culture medium, and malondialdehyde content of B. dothidea mycelia. Notably, the analysis of key enzymes in glycolysis pathway showed that the activity of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK), Ca2+Mg2+-ATPase were significantly increased after FBS treatment. But the glucose contents were significantly reduced, and pyruvate contents were significantly increased in B. dothidea after treatment with FBS. CONCLUSIONS: The inhibitory mechanism of S. spiroverticillatus HS1 against B. dothidea was a complex process, which was associated with multiple levels of mycelial growth, cell membrane structure, material and energy metabolism. The FBS of S. spiroverticillatus HS1 could provide an alternative approach to biological control strategies against B. dothidea.


Subject(s)
Ascomycota , Mycelium , Plant Diseases , Populus , Streptomyces , Ascomycota/growth & development , Ascomycota/drug effects , Plant Diseases/microbiology , Plant Diseases/prevention & control , Streptomyces/physiology , Populus/microbiology , Mycelium/growth & development , Mycelium/drug effects , Antibiosis , Fermentation , Culture Media/chemistry
17.
Nat Commun ; 15(1): 8047, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39277621

ABSTRACT

Magnaporthe oryzae is a devastating fungal pathogen that causes the rice blast disease worldwide. The post-translational modification of ADP-ribosylation holds significant importance in various fundamental biological processes. However, the specific function of this modification in M. oryzae remains unknown. This study revealed that Poly(ADP-ribosyl)ation (PARylation) executes a critical function in M. oryzae. M. oryzae Poly(ADP-ribose) polymerase 1 (PARP1) exhibits robust PARylation activity. Disruption of PARylation by PARP1 knock-out or chemical inhibition reveals its involvement in M. oryzae virulence, particularly in appressorium formation. Furthermore, we identified two M. oryzae 14-3-3 proteins, GRF1 and GRF2, as substrates of PARP1. Deletion of GRF1 or GRF2 results in delayed and dysfunctional appressorium, diminished plant penetration, and reduced virulence of the fungus. Biochemical and genetic evidence suggest that PARylation of 14-3-3s is essential for its function in M. oryzae virulence. Moreover, PARylation regulates 14-3-3 dimerization and is required for the activation of the mitogen-activated protein kinases (MAPKs), Pmk1 and Mps1. GRF1 interacts with both Mst7 and Pmk1, and bridges their interaction in a PARylation-dependent manner. This study unveils a distinctive mechanism that PARylation of 14-3-3 proteins controls appressorium formation through MAPK activation, and could facilitate the development of new strategies of rice blast disease control.


Subject(s)
14-3-3 Proteins , Fungal Proteins , Oryza , Plant Diseases , 14-3-3 Proteins/metabolism , 14-3-3 Proteins/genetics , Virulence , Oryza/microbiology , Plant Diseases/microbiology , Fungal Proteins/metabolism , Fungal Proteins/genetics , ADP-Ribosylation , Poly (ADP-Ribose) Polymerase-1/metabolism , Poly (ADP-Ribose) Polymerase-1/genetics , Ascomycota/pathogenicity , Ascomycota/genetics , Ascomycota/metabolism , Magnaporthe/pathogenicity , Magnaporthe/genetics , Magnaporthe/metabolism , Protein Processing, Post-Translational
18.
Nutr Diabetes ; 14(1): 71, 2024 09 03.
Article in English | MEDLINE | ID: mdl-39223127

ABSTRACT

Type 2 diabetes mellitus (T2DM) is globally recognized as a significant health concern, with diabetic foot (DF) identified as a severe long-term complication that can lead to tissue death or amputation. The discovery of the impact of mycobiota, a diverse group of multicellular eukaryotes in the gut microbiome, on the onset of endocrine disorders holds great significance. Therefore, this research aimed to examine variations in fungal mycobiome and identify potential biomarkers for T2DM and T2DM-DF. Fecal and blood samples were collected from 33 individuals with T2DM, 32 individuals with T2DM-DF, and 32 healthy individuals without any health conditions (HC). Blood samples were used for laboratory parameters analysis, while total DNA was extracted from fecal samples and sequenced using Illumina 18s rRNA. Bioinformatics tools were employed to analyze fungal abundance and diversity, revealing differentially expressed fungal species and signature fungi that distinguished between T2DM, T2DM-DF, and HC groups. Firstly, significant alterations in some laboratory parameters were observed among the three groups, which also differed between T2DM and T2DM-DF. The diversity of gut fungi in T2DM and T2DM-DF significantly differed from that of the HC group; however, more pronounced changes were observed in T2DM-DF. Additionally, two significantly altered phyla, Ascomycota and Basidiomycota, were identified with higher Ascomycota abundance but lower Basidiomycota abundance in both the T2DM and T2DM-DF compared to the HC group. Furthermore, the top 15 fungi showing significant changes at the species level included a notable decrease in Rhodotorula_mucilaginosa abundance in patients with T2DM compared to HC and a substantial increase in unclassified_g_Candida abundance specifically seen only among patients with T2DM-DF, but not among those diagnosed with T2DM or HC. Thirdly, KEGG was employed to analyze enzyme expression across the three groups, revealing a more pronounced alteration in gut fungal function within T2DM-DF compared to T2DM. Subsequently, to accurately identify signature fungi in each group, a random forest was utilized to rank the top 15 significant fungi. Notably, 11 fungi were identified as potential biomarkers for distinguishing T2DM or T2DM-DF from HC, while eight fungi could discriminate between T2DM and T2DM-DF. Furthermore, receiver operating characteristic curve (ROC) analysis demonstrated enhanced accuracy of predicted outcomes. These findings suggest that changes in fungal mycobiome are closely associated with the progression and complications of T2DM and DF, offering promising prospects for diagnosis and treatment.


Subject(s)
Biomarkers , Diabetes Mellitus, Type 2 , Diabetic Foot , Dysbiosis , Feces , Gastrointestinal Microbiome , Mycobiome , Humans , Diabetes Mellitus, Type 2/microbiology , Diabetes Mellitus, Type 2/complications , Middle Aged , Female , Male , Dysbiosis/microbiology , Dysbiosis/diagnosis , Diabetic Foot/microbiology , Biomarkers/blood , Feces/microbiology , Aged , Adult , Ascomycota , Basidiomycota , Case-Control Studies , Fungi/isolation & purification
19.
Appl Microbiol Biotechnol ; 108(1): 458, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39230670

ABSTRACT

The advancement of fungal biocontrol agents depends on replacing cereal grains with low-cost agro-industrial byproducts for their economical mass production and development of stable formulations. We propose an innovative approach to develop a rice flour-based formulation of the beneficial biocontrol agent Trichoderma asperelloides CMAA1584 designed to simulate a micro-bioreactor within the concept of full biorefinery process, affording in situ conidiation, extended shelf-life, and effective control of Sclerotinia sclerotiorum, a devastating pathogen of several dicot agricultural crops worldwide. Rice flour is an inexpensive and underexplored byproduct derived from broken rice after milling, capable of sustaining high yields of conidial production through our optimized fermentation-formulation route. Conidial yield was mainly influenced by nitrogen content (0.1% w/w) added to the rice meal coupled with the fermentor type. Hydrolyzed yeast was the best nitrogen source yielding 2.6 × 109 colony-forming units (CFU)/g within 14 days. Subsequently, GControl, GLecithin, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru formulations were obtained by extrusion followed by air-drying and further assessed for their potential to induce secondary sporulation in situ, storage stability, and efficacy against Sclerotinia. GControl, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru stood out with the highest number of CFU after sporulation upon re-hydration on water-agar medium. Shelf-life of formulations GControl and GBentonite remained consistent for > 3 months at ambient temperature, while in GBentonite and GOrganic compost+Break-Thru formulations remained viable for 24 months during refrigerated storage. Formulations exhibited similar efficacy in suppressing the myceliogenic germination of Sclerotinia irrespective of their concentration tested (5 × 104 to 5 × 106 CFU/g of soil), resulting in 79.2 to 93.7% relative inhibition. Noteworthily, all 24-month-old formulations kept under cold storage successfully suppressed sclerotia. This work provides an environmentally friendly bioprocess method using rice flour as the main feedstock to develop waste-free granular formulations of Trichoderma conidia that are effective in suppressing Sclerotinia while also improving biopesticide shelf-life. KEY POINTS: • Innovative "bioreactor-in-a-granule" system for T. asperelloides is devised. • Dry granules of aerial conidia remain highly viable for 24 months at 4 °C. • Effective control of white-mold sclerotia via soil application of Trichoderma-based granules.


Subject(s)
Ascomycota , Bioreactors , Fermentation , Oryza , Spores, Fungal , Bioreactors/microbiology , Ascomycota/growth & development , Ascomycota/metabolism , Oryza/microbiology , Spores, Fungal/growth & development , Nitrogen/metabolism , Hypocreales/metabolism , Hypocreales/growth & development , Biological Control Agents/chemistry , Trichoderma/metabolism , Trichoderma/growth & development , Plant Diseases/microbiology , Plant Diseases/prevention & control
20.
Sci Data ; 11(1): 964, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39231989

ABSTRACT

Discinaceae holds significant importance within the Pezizales, representing a prominent group of macroascomycetes distributed globally. However, there is a dearth of genomic studies focusing on this family, resulting in gaps in our understanding of its evolution, development, and ecology. Here we utilized state-of-the-art genome assembly methodologies, incorporating third-generation single-molecule fluorescence and Hi-C-assisted methods, to elucidate the genomic landscapes of Gyromitra esculenta and Paragyromitra xinjiangensis. The genome sizes of two species were determined to be 47.10 Mb and 48.20 Mb, with 23 and 22 scaffolds, respectively. 10,438 and 11,469 coding proteins were identified, with functional annotations encompassing over 96.47% and 94.40%, respectively. Assessment of completeness using BUSCO revealed that 98.71% and 98.89% of the conserved proteins were identified. The application of comparative genomic technology has helped in identifying traits associated with of heterothallic life cycle traits and elucidating unique patterns of chromosomal evolution. Additionally, we identified potential saprotrophic nutritional modes and systematic phylogenetic relationships between the two species. Therefore, this study provides crucial genomic insights into the evolution, nutritional type, and ecological roles of species within the Pezizales.


Subject(s)
Ascomycota , Genome, Fungal , Ascomycota/genetics , Chromosomes , Fluorescence , Genome Size , Genomics , Phylogeny
SELECTION OF CITATIONS
SEARCH DETAIL