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Fungal cell walls represent the frontline contact with the host and play a prime role in pathogenesis. While the roles of the cell wall polymers like chitin and branched β‐glucan are well understood in vegetative and pathogenic development, that of the most prominent galactose‐containing polymers galactosaminogalactan and fungal‐type galactomannan is unknown in plant pathogenic fungi. Mining the genome of the maize pathogen Colletotrichum graminicola identified the single‐copy key galactose metabolism genes UGE1 and UGM1, encoding a UDP‐glucose‐4‐epimerase and UDP‐galactopyranose mutase, respectively. UGE1 is thought to be required for biosynthesis of both polymers, whereas UGM1 is specifically required for fungal‐type galactomannan formation. Promoter:eGFP fusion strains revealed that both genes are expressed in vegetative and in pathogenic hyphae at all stages of pathogenesis. Targeted deletion of UGE1 and UGM1, and fluorescence‐labeling of galactosaminogalactan and fungal‐type galactomannan confirmed that Δuge1 mutants were unable to synthesize either of these polymers, and Δugm1 mutants did not exhibit fungal‐type galactomannan. Appressoria of Δuge1, but not of Δugm1 mutants, were defective in adhesion, highlighting a function of galactosaminogalactan in the establishment of these infection cells on hydrophobic surfaces. Both Δuge1 and Δugm1 mutants showed cell wall defects in older vegetative hyphae and severely reduced appressorial penetration competence. On intact leaves of Zea mays, both mutants showed strongly reduced disease symptom severity, indicating that UGE1 and UGM1 represent novel virulence factors of C. graminicola. [ABSTRACT FROM AUTHOR]

Colletotrichum is an important plant pathogenic fungi that causes anthracnose/-twister disease in onion. This disease was prevalent in the monsoon season from August to November months and the symptoms were observed in most of the fields. This study aimed to investigate the pathogenicity and cumulative effect, if any of Colletotrichum gloeosporioides and Fusarium acutatum. The pot experiment was laid out to identify the cause responsible for inciting anthracnose-twister disease, whether the Colletotrichum or Fusarium or both, or the interaction of pathogens and GA3. The results of the pathogenicity test confirmed that C. gloeosporioides and F. acutatum are both pathogenic. C. gloeosporioides caused twisting symptoms independently, while F.acutatum independently caused only neck elongation. The independent application of GA3 did not produce any symptoms, however, increased the plant height. The combined treatment of C. gloeosporioides and F. acutatum caused twisting, which enhanced upon interaction with GA3 application giving synergistic effect. The acervuli were found in lesions infected with C. gloeosporioides after 8 days of inoculation on the neck and leaf blades. Symptoms were not observed in untreated control plants. Koch's postulates were confirmed by reisolating the same pathogens from the infected plants. [ABSTRACT FROM AUTHOR]

Colletotrichum scovillei, a member of the Colletotrichum acutatum species complex, causes severe anthracnose of pepper fruit, reducing yield and quality. However, the molecular mechanisms underlying its pathogenesis are unknown. Ste7 kinase in the Fus3/Kss1-related mitogen protein kinase signaling pathway plays an important role in plant infection by phytopathogenic fungi. In this study, the function of CsSTE7, an ortholog of Ste7, was investigated in C. scovillei using a targeted gene deletion mutant (ΔCsste7). Compared to the wild type, ΔCsste7 had normal mycelial growth, but conidial morphology, germination of conidia, and tolerance to cell wall integrity and osmotic stresses were defective. Importantly, ΔCsste7 was completely defective in appressorium formation and causing anthracnose on pepper fruits. These defects were restored in the complemented strain (Csste7c). The results suggest that CsSTE7 is essential for development and pathogenicity of C. scovillei. [ABSTRACT FROM AUTHOR]

Natural rubber is an important national strategic and industrial raw material. The leaf anthracnose of rubber trees caused by the Colletotrichum species is one of the important factors restricting the yields of natural rubber. In this study, we isolated and identified strain Bacillus velezensis SF334, which exhibited significant antagonistic activity against both C. australisinense and C. siamense, the dominant species of Colletotrichum causing rubber tree leaf anthracnose in the Hainan province of China, from a pool of 223 bacterial strains. The cell suspensions of SF334 had a significant prevention effect for the leaf anthracnose of rubber trees, with an efficacy of 79.67% against C. siamense and 71.8% against C. australisinense. We demonstrated that SF334 can lead to the lysis of C. australisinense and C. siamense mycelia by causing mycelial expansion, resulting in mycelial rupture and subsequent death. B. velezensis SF334 also harbors some plant probiotic traits, such as secreting siderophore, protease, cellulase, pectinase, and the auxin of indole-3-acetic acid (IAA), and it has broad-spectrum antifungal activity against some important plant pathogenic fungi. The genome combined with comparative genomic analyses indicated that SF334 possesses most genes of the central metabolic and gene clusters of secondary metabolites in B. velezensis strains. To our knowledge, this is the first time a Bacillus velezensis strain has been reported as a promising biocontrol agent against the leaf anthracnose of rubber trees caused by C. siamense and C. australisinense. The results suggest that B. velezensis could be a potential candidate agent for the leaf anthracnose of rubber trees. [ABSTRACT FROM AUTHOR]

Summary: Monoterpenes are the most prevalent compounds found in essential oils. They exhibit inhibitory actions against phytopathogenic postharvest fungi. Direct application limits their effectiveness due to their instability, high volatility, hydrophobicity and susceptibility to degradation. Encapsulation systems using metal–organic frameworks (MOFs) have been developed to maximise their use. In this study, four protocols were shown to encapsulate thymol and limonene in porous solids, such as ZIF‐8, UiO‐66‐(COOH)2 and zeolite 13X. Vapourisation and diffusion at 60 °C for 16 h was found to be the most efficient encapsulation process. A larger amount of thymol than limonene was loaded in the porous solids. Thymol released from MOFs slowed down the growth of Colletotrichum musae by up to 6 days at 25 °C. There was a sustained release of thymol even beyond the period of maximum fungal growth. This proof‐of‐concept study revealed the potential utility of MOFs as carriers of thymol against postharvest fungi. [ABSTRACT FROM AUTHOR]

Summary: N‐linked protein glycosylation is a conserved and essential modification mediating protein processing and quality control in the endoplasmic reticulum (ER), but how this contributes to the infection cycle of phytopathogenic fungi is largely unknown.In this study, we discovered that inhibition of protein N‐glycosylation severely affected vegetative growth, hyphal tip development, conidial germination, appressorium formation, and, ultimately, the ability of the maize (Zea mays) anthracnose pathogen Colletotrichum graminicola to infect its host.Quantitative proteomics analysis showed that N‐glycosylation can coordinate protein O‐glycosylation, glycosylphosphatidylinositol anchor modification, and endoplasmic reticulum quality control (ERQC) by directly targeting the proteins from the corresponding pathway in the ER. We performed a functional study of the N‐glycosylation pathway‐related protein CgALG3 and of the ERQC pathway‐related protein CgCNX1, which demonstrated that N‐glycosylation of ER chaperone proteins is essential for effector stability, secretion, and pathogenicity of C. graminicola.Our study provides concrete evidence for the regulation of effector protein stability and secretion by N‐glycosylation. [ABSTRACT FROM AUTHOR]

Background: Colletotrichum camelliae, one of the most important phytopathogenic fungi infecting tea plants (Camellia sinensis), causes brown blight disease resulting in significant economic losses in yield of some sensitive cultivated tea varieties. To better understand its phytopathogenic mechanism, the genetic information is worth being resolved. Results: Here, a high-quality genomic sequence of C. camelliae (strain LT-3-1) was sequenced using PacBio RSII sequencing platform, one of the most advanced Three-generation sequencing platforms and assembled. The result showed that the fungal genomic sequence is 67.74 Mb in size (with the N50 contig 5.6 Mb in size) containing 14,849 putative genes, of which about 95.27% were annotated. The data revealed a large class of genomic clusters potentially related to fungal pathogenicity. Based on the Pathogen Host Interactions database, a total of 1698 genes (11.44% of the total ones) were annotated, containing 541 genes related to plant cell wall hydrolases which is remarkably higher than those of most species of Colletotrichum and others considered to be hemibiotrophic and necrotrophic fungi. It's likely that the increase in cell wall-degrading enzymes reflects a crucial adaptive characteristic for infecting tea plants. Conclusion: Considering that C. camelliae has a specific host range and unique morphological and biological traits that distinguish it from other species of the genus Colletotrichum, characterization of the fungal genome will improve our understanding of the fungus and its phytopathogenic mechanism as well. [ABSTRACT FROM AUTHOR]

The cell wall integrity (CWI) signaling pathway plays important roles in the dissemination and infection of several plant pathogenic fungi. However, its roles in the pepper fruit anthracnose fungus Colletotrichum scovillei remain uninvestigated. In this study, the major components of the CWI signaling pathway--CsMCK1 (MAPKKK), CsMKK1 (MAPKK), and CsMPS1 (MAPK)--were functionally characterized in C. scovillei via homology-dependent gene replacement. The DCsmck1, DCsmkk1, and DCsmps1 mutants showed impairments in fungal growth, conidiation, and tolerance to CWI and salt stresses. Moreover, DCsmck1, DCsmkk1, and DCsmps1 failed to develop anthracnose disease on pepper fruits due to defects in appressorium formation and invasive hyphae growth. These results suggest that CsMCK1, CsMKK1, and CsMPS1 play important roles in mycelial growth, conidiation, appressorium formation, plant infection, and stress adaption of C. scovillei. These findings will contribute to a better understanding of the roles of the CWI signaling pathway in the development of pepper fruit anthracnose disease. [ABSTRACT FROM AUTHOR]

Background: A diverse set of antimicrobial molecules have been found mainly in the seeds and fruits of Capsicum annuum UENF1381, accession resistant to different phytopathogenic microorganisms, like bacteria of the genus Xanthomonas and fungi of the genus Colletotrichum. However, there is little information about the defense mechanisms in other plant organs. The work aimed to study the induction of resistance in leaves and roots of C. annuum through the identification and characterization of antimicrobial peptides against Colletotrichum scovillei, one of the main pathogens of the crop. Results: Based on the results of differential protein expression in response to infection, the extracts, LC48 (Control Leaf mock inoculated 48 h), and RC48 (Control Root mock inoculated 48 h) were selected. Analysis on the HPLC system resulted in 23 fractions (L1 to L23) obtained from the LC48 extract and 27 fractions from the RC48 extract (R1 to R27). Our results show that 10 μg mL−1 of the L1 fraction is able to inhibit 88.4% of fungal growth, causing cell membrane permeabilization, endogenous reactive oxygen species induction and mitochondrial activity reduction. The peptide in the L1 fraction, named CaLPI, showed similarities with different sequences of proteinase inhibitors. Conclusion: The study provides information on the diversity of antimicrobial proteins and peptides present in the leaves and roots of C. annuum UENF1381. With these results, we hope to contribute to the use of peptides as potential molecules in microbial control. [ABSTRACT FROM AUTHOR]

Colletotrichum siamense causes rubber tree anthracnose and significant losses for the natural rubber industry. Here, actinomycete strains YQ-33, QZ-9 and WZ-2 were isolated, found to have high antagonistic activity against C. siamense and preliminarily identified as Streptomyces sp. Millet broth was the optimal medium for all strains to produce antifungal metabolites against C. siamense, and the millet broth culture filtrate from each strais greatly inhibited conidial germination and appressorial formation of C. siamense. Of the three strains, QZ-9 had relatively broad antifungal activity; its culture filtrate provided inhibition rates over 80% against mycelial growth of seven plant pathogenic fungi. Culture filtrates of QZ-9 and WZ-2 also reduced lesion size on rubber tree leaves and are promising candidates for control of rubber anthracnose. [ABSTRACT FROM AUTHOR]

A novel polymycovirus isolated from the plant-pathogenic fungus Colletotrichum gloeosporioides was identified. The viral genome is composed of nine double-stranded RNA segments, ranging in size from 699 bp to 2,444 bp. With the exception of dsRNA5, which contains two open reading frames (ORF5-1 and ORF5-2), the other dsRNA segments each contain one ORF. The proteins encoded by ORFs 1–8 are homologous to the proteins encoded by ORFs 1–8 of Colletotrichum camelliae filamentous virus 1 (CcFV-1). The amino acid sequences of the RNA-dependent RNA polymerase (RdRp) encoded by ORF1 and the viral methyltransferase encoded by ORF3 share 87.6% and 83.3% identity with CcFV-1. The proline-alanine-serine-rich protein (PASrp) encoded by ORF4 shares 86.6% sequence identity with that of CcFV-1. The proteins encoded by ORFs 2, 5 − 1, 6, 7, and 8 share 86.6%, 82.5%, 89.0%, 45.7%, and 95.5% sequence identity, respectively, with the corresponding proteins of CcFV-1. dsRNA9 is a defective copy of dsRNA2 that lacks a stretch of 1556 bp (nt 519 to nt 2074). Phylogenetic analysis based on the RdRp protein indicated that the novel virus clustered with members of the family Polymycoviridae, and based on the above results, we have tentatively named it "Colletotrichum gloeosporioides polymycovirus virus 1" (CgPmV1). To our knowledge, this is the first report of a polymycovirus with a defective dsRNA genome in C. gloeosporioides. [ABSTRACT FROM AUTHOR]

Autophagy serves as a survival mechanism and plays important role in nutrient recycling under conditions of starvation, nutrient storage, ad differentiation of plant pathogenic fungi. However, autophagy-related genes have not been investigated in Colletotrichum scovillei, a causal agent of pepper fruit anthracnose disease. ATG8 is involved in autophagosome formation and is considered a marker of autophagy. Therefore, we generated an ATG8 deletion mutant, DCsatg8, via homologous recombination to determine the functional roles of CsATG8 in the development and virulence of C. scovillei. Compared with the wild-type, the deletion mutant DCsatg8 exhibited a severe reduction in conidiation. Conidia produced by DCsatg8 were defective in survival, conidial germination, and appressorium formation. Moreover, conidia of DCsatg8 showed reduced lipid amount and PTS1 selectivity. A virulence assay showed that anthracnose development on pepper fruits was reduced in DCsatg8. Taken together, our results suggest that CsATG8 plays various roles in conidium production and associated development, and virulence in C. scovillei. [ABSTRACT FROM AUTHOR]

However, we have recently discovered multiple effector genes, named " I EPC i genes", that are involved in the host specificity of I C. orbiculare i to cucurbitaceous crops. In the subsequent search for novel factors involved in the host invasion mechanism via appressoria, pathogenicity-defective I C. orbiculare i mutants were screened from the mutant libraries of I C. orbiculare i , which were generated by plasmid insertional mutagenesis. 7500937 23 Takano Y, Kubo Y, Kuroda I, Furusawa I (1997) Temporal transcriptional pattern of three melanin biosynthesis genes, PKS1, SCD1, and THR1, in appressorium-differentiating and nondifferentiating conidia of Colletotrichum lagenarium. This article is an abstract of the paper presented by a winner of the Society Fellowship at the 2022 Annual Meeting of the Phytopathological Society of Japan in Sapporo (online). [Extracted from the article]

Aim: To identify and analyse genes that encode pectinases in the genome of the fungus Colletotrichum lindemuthianum, evaluate the expression of these genes, and compare putative pectinases found in C. lindemuthianum with pectinases produced by other fungi and oomycetes with different lifestyles. Methods and Results: Genes encoding pectinases in the genome of C. lindemuthianum were identified and analysed. The expression of these genes was analysed. Pectinases from C. lindemuthianum were compared with pectinases from other fungi that have different lifestyles, and the pectinase activity in some of these fungi was quantified. Fifty‐eight genes encoding pectinases were identified in C. lindemuthianum. At least six types of enzymes involved in pectin degradation were identified, with pectate lyases and polygalacturonases being the most abundant. Twenty‐seven genes encoding pectinases were differentially expressed at some point in C. lindemuthianum during their interactions with their host. For each type of pectinase, there were at least three isoenzyme groups. The number of pectinases present in fungi with different lifestyles seemed to be related more to the lifestyle than to the taxonomic relationship between them. Only phytopathogenic fungi showed pectate lyase activity. Conclusions: The collective results demonstrate the pectinolytic arsenal of C. lindemuthianum, with many and diverse genes encoding pectinases more than that found in other phytopathogens, which suggests that at least part of these pectinases must be important for the pathogenicity of the fungus C. lindemuthianum. Significance and Impact of the Study: Knowledge of these pectinases could further the understanding of the importance of this broad pectinolytic arsenal in the common bean infection and could be exploited for biotechnological purposes. [ABSTRACT FROM AUTHOR]

Bioactivity with antifungal properties has already been reported for some species of the genus Dipteryx. However, little is known about Dipteryx punctata. We evaluated the antifungal activity, in vitro and in vivo, of extracts of leaves, branches and fruits of D. punctata on Colletotrichum musae, the causal agent of anthracnose in bananas. The extracts and the coumarin standard were tested in vitro, at concentrations of 10%, 20%, 30%, 40%, and 50% (w/v), added in potato-dextrose-agar (PDA) medium. The experimental design was completely randomized, factorial design, with four replications. The average diameter of the fungal colonies was evaluated daily for eight days, and at the end, the percentage of inhibition and growth rates were calculated. For in vivo tests, the products were tested at concentrations of 40% and 50%, in preventive and curative applications. In these tests, three medium disks (5 mm) containing phytopathogen structures were deposited at opposite points of the fruits, and remained in a humid chamber for 48 h. Anthracnose lesions were measured at an interval of two days, up to eight days after fungus inoculation. In the in vitro essay, the extracts of the branches and residues of the fruits of D. punctata and the coumarin pattern caused the biggest reductions in the average diameter of the colonies of the phytopathogen. D. punctata and coumarin extracts were promising in terms of in vivo antifungal activity, especially in preventive applications, being an important source of investigation for the formulation of natural products as sustainable phytosanitary measures. [ABSTRACT FROM AUTHOR]

The HOG MAPK pathway mediates diverse cellular and physiological processes, including osmoregulation and fungicide sensitivity, in phytopathogenic fungi. However, the molecular mechanisms underlying HOG MAPK pathway-associated stress homeostasis and pathophysiological developmental events are poorly understood. Here, we demonstrated that the oxalate decarboxylase CsOxdC3 in Colletotrichum siamense interacts with the protein kinase kinase CsPbs2, a component of the HOG MAPK pathway. The expression of the CsOxdC3 gene was significantly suppressed in response to phenylpyrrole and tebuconazole fungicide treatments, while that of CsPbs2 was upregulated by phenylpyrrole and not affected by tebuconazole. We showed that targeted gene deletion of CsOxdC3 suppressed mycelial growth, reduced conidial length, and triggered a marginal reduction in the sporulation characteristics of the Δ CsOxdC3 strains. Interestingly, the Δ CsOxdC3 strain was significantly sensitive to fungicides, including phenylpyrrole and tebuconazole, while the CsPbs2 -defective strain was sensitive to tebuconazole but resistant to phenylpyrrole. Additionally, infection assessment revealed a significant reduction in the virulence of the Δ CsOxdC3 strains when inoculated on the leaves of rubber tree (Hevea brasiliensis). From these observations, we inferred that CsOxdC3 crucially modulates HOG MAPK pathway-dependent processes, including morphogenesis, stress homeostasis, fungicide resistance, and virulence, in C. siamense by facilitating direct physical interactions with CsPbs2. This study provides insights into the molecular regulators of the HOG MAPK pathway and underscores the potential of deploying OxdCs as potent targets for developing fungicides. [ABSTRACT FROM AUTHOR]

Colletotrichum fructicola is a globally significant phytopathogenic fungus. Mycovirus-induced hypovirulence has great potential for biological control and study of fungal pathogenic mechanisms. We previously reported that the mycovirus Colletotrichum alienum partitivirus 1 (CaPV1) is associated with the hypovirulence of C. fructicola , and the present study aimed to further investigate a host factor and its roles in mycovirus-induced hypovirulence. A gene named CfKOB1 , which encodes putative protein homologous to the β-subunit of voltage-gated potassium channels and aldo–keto reductase, is downregulated upon CaPV1 infection and significantly upregulated during the early infection phase of Nicotiana benthamiana by C. fructicola. Deleting the CfKOB1 gene resulted in diminished vegetative growth, decreased production of asexual spores, hindered appressorium formation, reduced virulence, and altered tolerance to abiotic stresses. Transcriptome analysis revealed that CfKOB1 regulates many metabolic pathways as well as the cell cycle and apoptosis. Furthermore, enhanced apoptosis was observed in the Δ CfKOB1 mutants. Viral RNA accumulation was significantly increased in the CfKOB1 deletion mutant. Additionally, our findings demonstrated that CaPV1 infection in the WT strain also induced cell apoptosis. Collectively, these results highlight the diverse biological roles of the CfKOB1 gene in the fungus C. fructicola , while it also participates in mycovirus-induced hypovirulence by regulating apoptosis. • A gene named CfKOB1 was confirmed to regulate development and pathogenicity of C. fructicola. • The CfKOB1 gene is downregulated upon mycovirus CaPV1 infection. • Deletion of CfKOB1 enhances cell apoptosis of C. fructicola. • CfKOB1 plays a negative role in viral RNA accumulation in the CaPV1 infected host fungus. • CfKOB1 associated cell apoptosis participates in mycovirus-induced hypovirulence in C. fructicola. [ABSTRACT FROM AUTHOR]

In this study, a novel positive-sense single-stranded RNA (1ssRNA) mycovirus, tentatively named Colletotrichum fructicola RNA virus 1 (CfRV1), was identified in the phytopathogenic fungus Colletotrichum fructicola. CfRV1 has seven genomic components, encoding seven proteins from open reading frames (ORFs) flanked by highly conserved untranslated regions (UTRs). Proteins encoded by ORFs 1, 2, 3, 5, and 6 are more similar to the putative RNA-dependent RNA polymerase (RdRp), hypothetical protein (P2), methyltransferase, and two hypothetical proteins of Hadaka virus 1 (HadV1), a capsidless 10- or 11-segmented 1ssRNA virus, while proteins encoded by ORFs 4 and 7 showed no detectable similarity to any known proteins. Notably, proteins encoded by ORFs 1 to 3 also share considerably high similarity with the corresponding proteins of polymycoviruses. Phylogenetic analysis conducted based on the amino acid sequence of CfRV1 RdRp and related viruses placed CfRV1 and HadV1 together in the same clade, close to polymycoviruses and astroviruses. CfRV1-infected C. fructicola strains demonstrate a moderately attenuated growth rate and virulence compared to uninfected isolates. CfRV1 is capsidless and potentially encapsulated in vesicles inside fungal cells, as revealed by transmission electron microscopy. CfRV1 and HadV1 are 1ssRNA mycoviruses closely related to polymycoviruses and astroviruses, represent a new linkage between 1ssRNA viruses and the intermediate double-stranded RNA (dsRNA) polymycoviruses, and expand our understanding of virus diversity, taxonomy, evolution, and biological traits. [ABSTRACT FROM AUTHOR]

Summary: Colletotrichum higginsianum is an important fungal pathogen causing anthracnose disease of cruciferous plants. In this study, we characterized a putative orthologue of yeast SPE1 in C. higginsianum, named ChODC. Deletion mutants of ChODC were defective in hyphal and conidial development. Importantly, deletion of ChODC significantly affected appressorium‐mediated penetration in C. higginsianum. However, polyamines partially restore appressorium function and virulence indicating that loss of ChODC caused significantly decreased virulence by the crosstalk between polyamines and other metabolic pathways. Subsequently, transcriptomic and metabolomic analyses demonstrated that ChODC played an important role in metabolism of various carbon and nitrogen compounds including amino acids, carbohydrates and lipids. Along with these clues, we found deletion of ChODC affected glycogen and lipid metabolism, which were important for conidial storage utilization and functional appressorium formation. Loss of ChODC affected the mTOR signalling pathway via modulation of autophagy. Interestingly, cAMP treatment restored functional appressoria to the ΔChODC mutant, and rapamycin treatment also stimulated formation of functional appressoria in the ΔChODC mutant. Overall, ChODC was associated with the polyamine biosynthesis pathway, as a mediator of cAMP and mTOR signalling pathways to regulate appressorium function. Our study provides evidence of a link between ChODC and the cAMP signalling pathway and defines a novel mechanism by which ChODC regulates infection‐associated autophagy and plant infection by fungi. [ABSTRACT FROM AUTHOR]

Colletotrichum camelliae is a widespread filamentous phytopathogenic fungus. In this study, a novel mycovirus designated as "Colletotrichum camelliae botourmiavirus 1" (CcBV1) was isolated from strain ZJQT11 of C. camelliae, and its complete genome sequence was determined. CcBV1 has a genome of 2,506 nucleotides and contains a large open reading frame (ORF) that encodes an RNA-dependent RNA polymerase (RdRp) with 672 amino acids and a predicted molecular mass of 75.23 kDa. A BLASTp search showed that RdRp encoded by CcBV1 is closely related to that of Pyricularia oryzae ourmia-like virus 1 with 73.22% identity. Phylogenetic analysis indicated that CcBV1 clustered in the penoulivirus clade within the family Botourmiaviridae. To the best of our knowledge, this is the first report of a penoulivirus in C. camelliae. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria, such as Bacillus spp., establish beneficial associations with plants and may inhibit the growth of phytopathogenic fungi. However, these bacteria are subject to multiple biotic stimuli from their competitors, causing stress and modifying their development. This work is a study of an in vitro interaction between two model microorganisms of socioeconomic relevance, using population dynamics and transcriptomic approaches. Co-cultures of Bacillus velezensis 83 with the phytopathogenic fungus Colletotrichum gloeosporioides 09 were performed to evaluate the metabolic response of the bacteria under conditions of non-nutritional limitation. The bacterial response was associated with the induction of a stress-resistant phenotype, characterized by a lower specific growth rate, but with antimicrobial production capacity. About 12% of co-cultured B. velezensis 83 coding sequences were differentially expressed, including the up-regulation of the general stress response (sigB regulon), and the down-regulation of alternative carbon sources catabolism (glucose preference). Defense strategies in B. velezensis are a determining factor in order to preserve the long-term viability of its population. Mostly, the presence of the fungus does not affect the expression of antibiosis genes, except for those corresponding to surfactin/bacillomycin D production. Indeed, the up-regulation of antibiosis genes expression is associated with bacterial growth, regardless of the presence of the fungus. This behavior in B. velezensis 83 resembles the strategy used by the classical Greek phalanx formation: by sacrificing growth rate and metabolic versatility, resources can be redistributed to defense (stress resistant phenotype) while maintaining the attack (antibiosis capacity). The presented results are the first characterization of the molecular phenotype at the transcriptome level of a biological control agent under biotic stress caused by a phytopathogen without nutrient limitation. [Display omitted] • Study of in vitro interaction between B. velezensis and C. gloeosporioides. • Colletotrichum modify growth rate and gene expression in Bacillus population. • Co-cultured Bacillus increased expression of SigB regulon as defense mechanism. • Up-expression of antibiosis-related genes is growth-associated. • Bacillus biocontrol strategy consist in a stress-resistant phenotype with antibiosis. [ABSTRACT FROM AUTHOR]

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 °C for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae. [ABSTRACT FROM AUTHOR]

In this study, a novel mitovirus designed "Colletotrichum higginsianum mitovirus 1" (ChMV1) was isolated from the phytopathogenic fungus Colletotrichum higginsianum. The genome of this mitovirus is 2,893 nt in length with an A + U content of 61% and contains a large open reading frame (ORF) encoding an RNA-dependent RNA polymerase (RdRp). A BLASTp analysis revealed that the RdRp domain of ChMV1 had 30.25% to 61.72% sequence identity to those of members of the genus Mitovirus and showed the highest degree of similarity (61.72% identity) to Botrytis cinerea mitovirus 3 (BcMV3). Phylogenetic analysis further indicated that ChMV1 is a member in the genus Mitovirus of the family Mitoviridae. To the best of our knowledge, this is the first report of a mitovirus in C. higginsianum. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to evaluate the antifungal and antibiofilm effects of essential oil (EO) from leaves of Lippia gracilis and its major constituents, thymol and carvacrol, against phytopathogenic fungi. Methods and Results: The leaves of L. gracilis were hydrodistilled to obtain the EO and the chemical composition was determined by GC/MS analysis. The antifungal activity of EO of L. gracilis was evaluated on the vegetative and mycelial growth of Colletotrichum gloeosporioides, Colletotrichum lindemuthianum, Fusarium oxysporum and Fusarium solani. In addition, the ability of the oil to inhibit fungal biofilm formation was assessed by total biomass quantification using crystal violet staining, analysis of metabolic activity, and scanning electron microscopy (SEM). Moreover the antifungal and antibiofilm activities of the monoterpenes, thymol and carvacrol, present in EO of L. gracilis were evaluated against F. oxysporum. The analysis of the chemical composition of EO extracted from L. gracilis, revealed the presence of monoterpenes (94·13%), which included carvacrol (48·57%) and thymol (7·78%), and 4 sesquiterpenes (3·74%). In general, EO showed significant antifungal activity and inhibited the formation of fungal biofilms. Furthermore, thymol and carvacrol showed significant antifungal and antibiofilm activities against F. oxysporum. SEM images showed structural changes in fungal morphology upon treatment with EO of L. gracilis. Conclusion: The results presented in this study showed promising antifungal and antibiofilm effects of EO of L. gracilis and its major components, carvacrol and thymol. Significance and Impact of the Study: These findings indicate that the EO extracted from L. gracilis, and the monoterpenes, carvacrol and thymol have a great potential as antifungal and antibiofilm agents. Furthermore, this is the first report of the antibiofilm activity of the EO of L. gracilis and its major components against phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

The genus Colletotrichum comprises a large number of filamentous fungi responsible for anthracnose diseases in many tropical and subtropical fruits and vegetables. In particular, Colletotrichum higginsianum infects Brassicaceae species, including Arabidopsis. The C. higginsianum strain IMI349063A is naturally infected with a dsRNA virus, named Colletorichum higginsianum non-segmented virus (ChNRV1). Here, we investigated the biological effect of ChNRV1 in C. higginsianum by comparing strains with and without the virus. ChNRV1 does not have an effect on C. higginsianum growth under salt and cell-wall stress conditions. However, thermal stress reduced C. higginsianum growth rate, this effect being more evident in the wild-type C. higginsianum strain containing the virus. Although ChNRV1 had no effect in conidiation, conidia were narrower when the virus is present. More importantly, ChNRV1 causes a mild increase in C. higginsianum virulence (hypervirulence) when infecting Arabidopsis plants. These findings indicated that, whereas the ChNRV1 mycovirus does not impair growth and conidiation of C. higginsianum, it confers hypervirulence to the fungal host. These findings will help in future research on the effect of mycoviral infection on pathogenic fungi in plant species of agronomical relevance. [ABSTRACT FROM AUTHOR]

The mycelial growth inhibition activities of different solvent extracts of root, stem and leaf of Helicteres angus- tifolia against --10 plant pathogenic fungi were studied by the mycelium growth rate method at --1.5 mg • mL --1. The inhibitory effects of root petroleum ether and root ethyl acetate extracts of Helicteres angustifolia on the spore germination in Col- letotrichurn musa wrere determined by spore germination method. The control effects of the root petroleum ether and root ethyl acetate extracts of Helicteres angustifolia against Colletotrichum musae wrere determined by in vitro method. The main components of root petroleum ether and ethyl acetate extracts of Helicteres angustifolia wrere analyzed by gas chromatography-mass spectrometer (GC-MS) , and the mycelial growth inhibition activities of eight main compounds against Colletotrichum musa wrere tested. The results wrere as follows ： Extracts each plant of Helicteres angustifolia showed different degrees of mycelial growth inhibitory effects on --10 plant pathogenic fungi. The mycelial growth inhibition rates of the root petroleum ether and ethyl acetate extracts of Helicteres angustifolia against Colletotrichum musae reached 87.00% and 86.--14% at --1.5 mg • mL--1 , and the EC.50 values were 0.062 and 0.052 mg • mL --1 , respectively. The relative inhibitory rates of the root petroleum ether and root ethyl acetate extracts of Helicteres angustifolia on the spore germination against Colletotrichum musae wrere more than 70% at 2, 4 and 8 mg • mL --1. At --10 mg • mL --1 , the control effects of the root petroleum ether and root ethyl acetate extracts of Helicteres angustifolia against Colletotrichum musae wrere 72.32% and 59.77%, respectively. The root petroleum ether and root ethyl acetate extracts of Helicteres angustifolia wrere analyzed by GC-MS. In total, 36 major chemical components were identified in the root petroleum ether extracts, --17 major chemical components were identified in the root ethyl acetate extracts. Among the selected eight major compounds, diisobutyl phthalate and dibutyl phthalate showed higher mycelial growth inhibitory effects against Colletotrichum musae. The inhibi - tion rates was 65.--12% and 68.07% at --100 pg • mL--1, respectively. The EC.50 values were 56.66 pg • mL--1 and 37.04 xg • mL --1 , respectively. [ABSTRACT FROM AUTHOR]

In the current study, a total of 70 fungi were isolated from the rhizosphere soil of chilli collected from six di erent districts of south Karnataka, India. All the rhizospheric fungi were evaluated for its antagonistic nature against Colletotrichum capsici-the causal agent of anthracnose disease-and eight isolates were found positive. The antagonistic fungi were further characterized for the production of plant growth-promoting traits wherein five isolates were recorded positive for all the traits tested and were also positive for root colonization. All five plant growth-promoting fungi (PGPF) were subjected to molecular characterization for identification up to the species level and the accession numbers were obtained from NCBI. The five isolates, namely NBP-08, NBP-45, NBP-61, NBP-66 and NBP-67, were further experimented with on susceptible seeds to evaluate its effcacy on seed and plant growth parameters along with induction of resistance against the anthracnose disease. The evaluated PGPF o ered significant enhancement in seed and plant growth parameters with maximum improvement observed in seeds treated with NBP-61. Among the PGPF isolates, NBP-61 showed the maximum protection of 78.75%, while all the other isolates also showed significant protection against anthracnose disease compared to untreated plants. The higher accumulation of lignin and callose deposition along with enhanced defense enzyme activities in the PGPF-treated challenge-inoculated seedlings authenticated the protection o ered by PGPF. The study evidenced the immense ability of PGPF in eliciting disease protection and enhancement of plant growth in chilli, which may act as a possible substitute for harmful chemicals. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) data directly indicated a Ca2+-dependent interaction between calmodulin (CaM) and CoDN3, a small effector of the plant pathogenic fungus Colletotrichum orbiculare, which is the causal agent of cucumber anthracnose. The overall conformation of CoDN3 is intrinsically disordered, and the CaM-binding site spans residues 34–53 of its C-terminal region. Experiments employing a chemically synthesized peptide corresponding to the CaM-binding site indicated that the CaM-binding region of CoDN3 in the Ca2+-bound CaM complex takes an α-helical conformation. Cell death suppression assay using a CoDN3 mutant lacking the CaM-binding ability suggested that the wild type CaM-binding site is necessary for full CoDN3 function in vivo. • CoDN3, an effector of the pathogenic microbe Colletotrichum orbiculare , interacts with calmodulin (CaM). • The binding between CoDN3 and CaM occurs in a Ca2+-dependent manner. • The CaM-bindings site of CoDN3 is located at its C-terminal half region, and is necessary for full CoDN3 function in vivo. • CoDN3 is an intrinsically disordered protein, but the CaM-binding region forms helical conformation when it binds to CaM. [ABSTRACT FROM AUTHOR]

Summary: To breach the plant cuticle, many plant pathogenic fungi differentiate specialized infection structures (appressoria). In Colletotrichum orbiculare (cucumber anthracnose fungus), this differentiation requires unique proper G1/S phase progression, regulated by two‐component GTPase activating protein CoBub2/CoBfa1 and GTPase CoTem1. Since their homologues regulate mitotic exit, cytokinesis, or septum formation from yeasts to mammals, we asked whether the BUB2 function in G1/S progression is specific to plant pathogenic fungi.Colletotrichum higginsianum and Magnaporthe oryzae were genetically analyzed to investigate conservation of BUB2 roles in cell cycle regulation, septum formation, and virulence. Expression profile of cobub2Δ was analyzed using a custom microarray.In bub2 mutants of both fungi, S phase initiation was earlier, and septum formation coordinated with a septation initiation network protein and contractile actin ring was impaired. Earlier G1/S transition in cobub2Δ results in especially high expression of DNA replication genes and differing regulation of virulence‐associated genes that encode proteins such as carbohydrate‐active enzymes and small secreted proteins. The virulence of chbub2Δ and mobub2Δ was significantly reduced.Our evidence shows that BUB2 regulation of G1/S transition and septum formation supports its specific requirement for appressorium development in plant pathogenic fungi. [ABSTRACT FROM AUTHOR]

Summary: To breach the plant cuticle, many plant pathogenic fungi differentiate specialized infection structures (appressoria). In Colletotrichum orbiculare (cucumber anthracnose fungus), this differentiation requires unique proper G1/S phase progression, regulated by two‐component GTPase activating protein CoBub2/CoBfa1 and GTPase CoTem1. Since their homologues regulate mitotic exit, cytokinesis, or septum formation from yeasts to mammals, we asked whether the BUB2 function in G1/S progression is specific to plant pathogenic fungi.Colletotrichum higginsianum and Magnaporthe oryzae were genetically analyzed to investigate conservation of BUB2 roles in cell cycle regulation, septum formation, and virulence. Expression profile of cobub2Δ was analyzed using a custom microarray.In bub2 mutants of both fungi, S phase initiation was earlier, and septum formation coordinated with a septation initiation network protein and contractile actin ring was impaired. Earlier G1/S transition in cobub2Δ results in especially high expression of DNA replication genes and differing regulation of virulence‐associated genes that encode proteins such as carbohydrate‐active enzymes and small secreted proteins. The virulence of chbub2Δ and mobub2Δ was significantly reduced.Our evidence shows that BUB2 regulation of G1/S transition and septum formation supports its specific requirement for appressorium development in plant pathogenic fungi. [ABSTRACT FROM AUTHOR]

Summary: The role of histone 3 lysine 4 (H3K4) methylation is poorly understood in plant pathogenic fungi. Here, we analysed the function of CclA, a subunit of the COMPASS complex mediating H3K4 methylation, in the brassica anthracnose pathogen Colletotrichum higginsianum. We show that CclA is required for full genome‐wide H3K4 trimethylation. The deletion of cclA strongly reduced mycelial growth, asexual sporulation and spore germination but did not impair the morphogenesis of specialized infection structures (appressoria and biotrophic hyphae). Virulence of the ΔcclA mutant on plants was strongly attenuated, associated with a marked reduction in appressorial penetration ability on both plants and inert cellophane membranes. The secondary metabolite profile of the ΔcclA mutant was greatly enriched compared to that of the wild type, with three different families of terpenoid compounds being overproduced by the mutant, namely the colletochlorins, higginsianins and sclerosporide. These included five novel molecules that were produced exclusively by the ΔcclA mutant: colletorin D, colletorin D acid, higginsianin C, 13‐epi‐higginsianin C and sclerosporide. Taken together, our findings indicate that H3K4 trimethylation plays a critical role in regulating fungal growth, development, pathogenicity and secondary metabolism in C. higginsianum. [ABSTRACT FROM AUTHOR]

Abstract Mandacaru (Cereus jamacaru DC.), is a cactaceous symbol of caatinga vegetation at Brazilian Northeast region, however, there are no much studies about biochemical properties of this species. Here, the pioneering study brings very relevant data to highlight the importance of research with endemic plants of the caatinga. Afterward, the presence of enzymes such as peroxidase, protease, chitinase, β-1,3-glucanase, and serine (trypsin) and cysteine (papain) protease inhibitors were evaluated. The peroxidase activity was higher in roots than other tissues. The β-1,3-glucanase and proteolytic activity were prominent in stem and roots. The chitinase activity and protease inhibitor for both classes analyzed were detected in the stem and fruit peel. Antifungal activity against Colletotrichum gloeosporioides showed the root extract has a promising inhibitory activity on this economical important phytopathogenic fungus. After the contact of the hyphae with root extract increase in membrane permeability, based on Propidium Iodide (PI) uptake, and production of reactive oxygen species (ROS) were detected, compared to negative control. In addition, Scanning Electron Microscopy (SEM) analysis showed morphological damage on hyphae structure indicating that the treatment debilitates either cell membrane or cell wall leading to the cell death C. gloeosporioides. Graphical abstract Image 1 Highlights • C. jamacaru is a source of antimicrobial proteins with biotechnological potential. • C. jamacaru has proteo-, chitinolytic, protease inhibitor, and peroxidase activity. • C. jamacaru roots extract inhibit fungal growth. • Root proteins have antifungal activity by inducing membrane pore formation. • SEM microscopy showed loss of internal content in treated fungi. [ABSTRACT FROM AUTHOR]

Phytopathogen genomes are under constant pressure to change, as pathogens are locked in an evolutionary arms race with their hosts, where pathogens evolve effector genes to manipulate their hosts, whereas the hosts evolve immune components to recognize the products of these genes. Colletotrichum higginsianum (Ch), a fungal pathogen with no known sexual morph, infects Brassicaceae plants including Arabidopsis thaliana. Previous studies revealed that Ch differs in its virulence toward various Arabidopsis thaliana ecotypes, indicating the existence of coevolutionary selective pressures. However, between-strain genomic variations in Ch have not been studied. Here, we sequenced and assembled the genome of a Ch strain, resulting in a highly contiguous genome assembly, which was compared with the chromosome-level genome assembly of another strain to identify genomic variations between strains. We found that the two closely related strains vary in terms of large-scale rearrangements, the existence of strain-specific regions, and effector candidate gene sets and that these variations are frequently associated with transposable elements (TEs). Ch has a compartmentalized genome consisting of gene-sparse, TE-dense regions with more effector candidate genes and gene-dense, TE-sparse regions harboring conserved genes. Additionally, analysis of the conservation patterns and syntenic regions of effector candidate genes indicated that the two strains vary in their effector candidate gene sets because of de novo evolution, horizontal gene transfer, or gene loss after divergence. Our results reveal mechanisms for generating genomic diversity in this asexual pathogen, which are important for understanding its adaption to hosts. [ABSTRACT FROM AUTHOR]

Streptomyces sp. has the potential to inhibit the incidence of fungal phytopathogens in crops due to their biochemical activity and the production of secondary metabolites. This work was aimed to identify and evaluate in vitro the antifungal potential of five strains of Streptomyces sp., isolated from desert soil, against Colletotrichum sp. The isolated strains were morphologically characterized by macroscopic and microscopic analysis, and their inhibition percentage against Colletotrichum sp. were determined by the dual challenge and well diffusion tests, applying a completely randomized design with three replicates. The inhibitory capacities of the five strains versus the phytopathogenic fungus varied considerably. Strains Q-84 and Q-60 showed the highest percentages of inhibition in the dual challenge test, with 92 and 88%, respectively. In the well diffusion test, the crude bioactive extract of strain Q-84 showed the highest inhibition (56%) statistically similar to that of commercial chemical fungicides AmistarTop® and Opera® (84 and 100%, respectively). All the strains displayed lipase activity and three of them (Q-84 included) also showed protease activity. The genetic characterization by 16S rDNA sequencing evidenced the homology of the strain Q-84 DNA to that of S. maritimus, further coincident with the lipase activity profile. Overall, the Q-84 showed potential to be used as biocontrol against Colletotrichum sp. [ABSTRACT FROM AUTHOR]

Plant pathogens have optimized their own effector sets to adapt to their hosts. However, certain effectors, regarded as core effectors, are conserved among various pathogens, and may therefore play an important and common role in pathogen virulence. We report here that the widely distributed fungal effector NIS1 targets host immune components that transmit signaling from pattern recognition receptors (PRRs) in plants. NIS1 from two Colletotrichum spp. suppressed the hypersensitive response and oxidative burst, both of which are induced by pathogen-derived molecules, in Nicotiana benthamiana. Magnaporthe oryzae NIS1 also suppressed the two defense responses, although this pathogen likely acquired the NIS1 gene via horizontal transfer from Basidiomycota. Interestingly, the root endophyte Colletotrichum tofieldiae also possesses a NIS1 homolog that can suppress the oxidative burst in N. benthamiana. We show that NIS1 of multiple pathogens commonly interacts with the PRR-associated kinases BAK1 and BIK1, thereby inhibiting their kinase activities and the BIK1-NADPH oxidase interaction. Furthermore, mutations in the NIS1-targeting proteins, i.e., BAK1 and BIK1, in Arabidopsis thaliana also resulted in reduced immunity to Colletotrichum fungi. Finally, M. oryzae lacking NIS1 displayed significantly reduced virulence on rice and barley, its hosts. Our study therefore reveals that a broad range of filamentous fungi maintain and utilize the core effector NIS1 to establish infection in their host plants and perhaps also beneficial interactions, by targeting conserved and central PRR-associated kinases that are also known to be targeted by bacterial effectors. [ABSTRACT FROM AUTHOR]

Lactobacillus plantarum, one of the most widespread lactic acid bacteria, exert a strong antagonistic activity against many microorganisms. The present study was conducted to determine in vitro and in situ antagonistic potential of L. plantarum (DSM 20174) for control postharvest decay caused by phytopathogenic fungi: Aspergillus flavus, Colletotrichum acutatum, Colletotrichum gloeosporioides, and Fusarium avenaceum. The results obtained in in vitro assays showed that L. plantarum had a stronger inhibitory effect on spore germination than on mycelia growth of all tested fungi. After 3 days of incubation, the diameter of inhibition zones ranged from 11.67 mm for C. gloeosporioides to 14.67 mm for C. acutatum. The bacterial suspension of L. plantarum significantly inhibited conidial germination of all postharvest pathogens (89.62-97.61%). In situ assays showed that treatment with L. plantarum efficiently inhibited necrosis ranging from 42.54% for C. acutatum to 54.47% for A. flavus. The disease incidence in L. plantarum treated fruits was statistically significantly lower than in the positive control for all fungi tested (P<0.05). The presented data demonstrate the antagonistic potential of L. plantarum (DSM 20174) and indicate the possibility of using this bacterial strain as a biological agent to control postharvest fungal pathogens. [ABSTRACT FROM AUTHOR]

Colletotrichum is a large genus of plant pathogenic fungi comprising more than 200 species. In this work, we present the genome sequences of four Colletotrichum species pathogenic to soybean: C. truncatum, C. plurivorum, C. musicola, and C. sojae. While C. truncatum's globally considered the most important pathogen, the other three species have been described and associated with soybean only recently. The genome sequences will provide insights into factors that contribute to pathogenicity toward soybean and will be useful for further research into the evolution of Colletotrichum. [ABSTRACT FROM AUTHOR]

Colletotrichum falcatum and Fusarium moniliforme are the causal agents of red-rot and pokkah boeng disease in sugarcane respectively, which are among the most destructive diseases in this crop worldwide. In this work, antifungal property of bacteria was evaluated against these two plant pathogenic fungi. Initially six bacterial strains were screened by dual culture technique and two strains Bacillus cereus MTCC 9017 and Pseudomonas monteilii MTCC 9796 were selected for further studies. Ethyl acetate extracts of culture filtrates of these two bacteria were obtained and assayed for antifungal potential by poisoned food method. Both of the bacterial isolates tested showed significant antifungal activity against Colletotrichum falcatum and Fusarium moniliforme. The results of this study indicate the possibility of further exploring B. cereus MTCC 9017 and P. monteilii MTCC 9796 as potential biocontrol agents. [ABSTRACT FROM AUTHOR]

Two homologous gene clusters for the biosynthesis of sesterterpenes betaestacins were identified from two phytopathogens, Phoma betae and Colletotrichum orbiculare . Heterologous expression of identified oxidation enzymes with previously-characterized PbTS1 (BtcA Pb ) resulted in the production of seven novel sesterterpenes. Although both strains possessed homologous enzymes, oxidation state of corresponding products were different from each other, suggesting that structural diversification of sesterterpene skeletons might be achieved by these homologous enzymes with different functions. [ABSTRACT FROM AUTHOR]

Plant endophytic fungi have been recognized as an important and a good source of natural bioactive products with potential application in agriculture, medicine and food industry. Chemical and biological studies of fungal metabolites originating from endophytic fungi isolated in Sri Lanka are relatively less studied. Therefore we investigated the chemistry and bioactivity of endophytic fungi present in leaves ofPiper nigrumL. (black pepper) of the family Piperaceae famed as the spices king due to its pungent quality. A fungal endophyte isolated from the leaves ofP. nigrumwas identified asColletotrichum siamensethrough molecular biological means using internal transcribed spacer (ITS) region of rDNA gene. This is the first report of the isolation ofC. siamensefrom Piperaceae. The fungus was fermented in potato dextrose media and the fungal media were extracted with EtOAc. Chromatographic separation of the EtOAc extract over silica gel, Sephadex LH-20 and preparative thin layer chromatography furnished indole-3-acetic acid (IAA) and uracil. IAA showed high antifungal activity against the common plant pathogenic fungusCladosporium cladosporiodiesby TLC bioautography method and antioxidant activity against DPPH radical by spectrophotometry method. [ABSTRACT FROM PUBLISHER]

BACKGROUND During the last few years, a growing number of antimicrobial peptides have been isolated from plants and particularly from seeds. Recent results from our laboratory have shown the purification of a new trypsin inhibitor, named CaTI, from chilli pepper ( Capsicum annuum L.) seeds. This study aims to evaluate the antifungal activity and mechanism of action of CaTI on phytopathogenic fungi and detect the presence of protease inhibitors in other species of this genus. RESULTS Our results show that CaTI can inhibit the growth of the phytopathogenic fungi Colletotrichum gloeosporioides and C. lindemuthianum. CaTI can also permeabilize the membrane of all tested fungi. When testing the inhibitor on its ability to induce reactive oxygen species, an induction of reactive oxygen species ( ROS) and nitric oxide ( NO) particularly in Fusarium species was observed. Using CaTI coupled to fluorescein isothiocyanate ( FITC), it was possible to determine the presence of the inhibitor inside the hyphae of the Fusarium oxysporum fungus. The search for protease inhibitors in other Capsicum species revealed their presence in all tested species. CONCLUSION This paper shows the antifungal activity of protease inhibitors such as CaTI against phytopathogenic fungi. Antimicrobial peptides, among which the trypsin protease inhibitor family stands out, are present in different species of the genus Capsicum and are part of the chemical arsenal that plants use to defend themselves against pathogens. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: The fungus Colletotrichum is a plant pathogen that causes the anthracnose disease, resulting in huge losses in various crops including the rose-scented geranium ( Pelargonium graveolens). Although the bacterial community associated with plants has an important role in the establishment of plant diseases, little is known about what happens in P. graveolens. Aims: To increase the knowledge about the bacterial community associated with P. graveolens and its relationship with anthracnose disease symptoms. Methods: Quantitative PCR and high-throughput sequencing were combined to determine the presence of the fungus Colletotrichum and to reveal the bacterial communities associated with different plant parts - root, stem and leaf - and in the rhizosphere and bulk soil, and also to determine the respective bacterial communities associated with P. graveolens leaves symptomatic and asymptomatic for anthracnose disease. Results: The fungus Colletotrichum was detected in all plant parts and in the surrounding soil. Bacterial communities varied spatially in plants, and the disease symptoms also influenced the composition of the bacterial community. Abundances of operational taxonomic units (OTUs) assigned to the phylum Actinobacteria and to the genus Streptococcus were greatly increased in asymptomatic leaves. Conclusions: The bacterial community associated to geranium leaves responds to anthracnose symptoms. [ABSTRACT FROM AUTHOR]

A new standardized method, using isothermal microcalorimetry (IMC), was established to determine thermokinetic parameters from heat flow curves and to demonstrate the reproducibility and repeatability of the parameters of five Colletotrichum species on different days. Measurements on IMC were made at different periods and by two operators. Repeatability and reproducibility (R&R) measurement system analysis was performed on the technique used to measure the heat flow of Colletotrichum strains. The results showed that the %GageR&R was found to be within the acceptable ranges of a measurement system. Also, the parameters obtained from the curves were subjected to a combination of Principal Component Analysis (PCA) and Clustering, the data showed that the total heat (H t) and maximum growth rate (μ max) are probably the most specific distinguishing characteristic of the strains evaluated in this study. This study demonstrates, for the first time, the usefulness of IMC in obtaining heat flow curves and thermokinetic parameters, providing repeatable and reproducible measurements over a period and under controlled conditions, for future identifications of phytopathogenic fungi. • Colletotrichum sp. characterization method by microcalorimetry was standardized • Heat flow measurements were repeatable and reproducible over time • Thermokinetic parameters were obtained from the integrated heat flow curves • Thermokinetic parameters discriminated fungi through PCA analysis • This is the first report on microcalorimetry usefulness for fungi identification [ABSTRACT FROM AUTHOR]

Based on the microwave-assisted synthetic protocol developed in our previous work, we have synthesized a series of novel furo[3,2- c ]coumarins as fused Osthole derivatives, via the reaction of 4-hydroxycoumarins and β -ketoesters catalyzed by DMAP. All the target compounds were evaluated in vitro for their antifungal activity against six phytopathogenic fungi, some compounds exhibited potential activity in the primary assays. Especially compounds 6c , 7b , 8b and 8c (shown in Fig. 1) were the most active ones, EC 50 values of these four compounds against Colletotrichum capsica , Botrytis cinerea and Rhizoctonia solani were further investigated. 6c was identified as the most promising candidate with the EC 50 value at 0.110 μM against Botrytis cinerea and 0.040 μM against Colletotrichum capsica , respectively, representing better antifungal activity than that of the commonly used fungicide Azoxystrobin. [ABSTRACT FROM AUTHOR]

Background: Accurate delimitation of plant pathogenic fungi is critical for the establishment of quarantine regulations, screening for genetic resistance to plant pathogens, and the study of ecosystem function. Concatenation analysis of multi-locus DNA sequence data represents a powerful and commonly used approach to recognizing evolutionary independent lineages in fungi. It is however possible to mask the discordance between individual gene trees, thus the speciation events might be erroneously estimated if one simply recognizes well supported clades as distinct species without implementing a careful examination of species boundary. To investigate this phenomenon, we studied Colletotrichum siamense s. lat., which is a cosmopolitan pathogen causing serious diseases on many economically important plant hosts. Presently there are significant disagreements among mycologists as to what constitutes a species in C. siamense s. lat., with the number of accepted species ranging from one to seven. Results: In this study, multiple approaches were used to test the null hypothesis "C. siamense is a species complex", using a global strain collection. Results of molecular analyses based on the Genealogical Concordance Phylogenetic Species Recognition (GCPSR) and coalescent methods (e.g. Generalized Mixed Yule-coalescent and Poisson Tree Processes) do not support the recognition of any independent evolutionary lineages within C. siamense s. lat. as distinct species, thus rejecting the null hypothesis. This conclusion is reinforced by the recognition of genetic recombination, cross fertility, and the comparison of ecological and morphological characters. Our results indicate that reproductive isolation, geographic and host plant barriers to gene flow are absent in C. siamense s. lat. Conclusions: This discovery emphasized the importance of a polyphasic approach when describing novel species in morphologically conserved genera of plant pathogenic fungi. [ABSTRACT FROM AUTHOR]

We investigated the phylogenetic diversity of 144 Colletotrichum isolates associated with symptomatic and asymptomatic tissues of Camellia sinensis and other Camellia spp. from seven provinces in China (Fujian, Guizhou, Henan, Jiangxi, Sichuan, Yunnan, Zhejiang), and seven isolates obtained from other countries, including Indonesia, UK, and the USA. Based on multi-locus (ACT, ApMat, CAL, GAPDH, GS, ITS, TUB2) phylogenetic analyses and phenotypic characters, 11 species were distinguished, including nine well-characterised species (C. alienum, C. boninense, C. camelliae, C. cliviae, C. fioriniae, C. fructicola, C. gloeosporioides, C. karstii, C. siamense), and two novel species (C. henanense and C. jiangxiense). Of these, C. camelliae proved to be the most dominant and probably host specific taxon occurring on Camellia. An epitype is also designated for the latter species in this study. Colletotrichum jiangxiense is shown to be phylogenetically closely related to the coffee berry pathogen C. kahawae subsp. kahawae. Pathogenicity tests and the pairwise homoplasy index test suggest that C. jiangxiense and C. kahawae subsp. kahawae are two independent species. This study represents the first report of C. alienum and C. cliviae occurring on Camellia sinensis. In addition, our study demonstrated that the combined use of the loci ApMat and GS in a phylogenetic analysis is able to resolve all currently accepted species in the C. gloeosporioides species complex. [ABSTRACT FROM AUTHOR]

The present work aimed to evaluate the defense responses induced by chemically sulfated ulvans in Arabidopsis thaliana plants against the phytopathogenic fungi Alternaria brassicicola and Colletotrichum higginsianum . Derivatives with growing sulfate content (from 20.9 to 36.6%) were prepared with SO 3 -pyridine complex in formamide. NMR and FTIR spectroscopic analyses confirmed the increase of sulfate groups after the chemical sulfation process. The native sulfated polysaccharide (18.9% of sulfate) and its chemically sulfated derivatives similarly reduced the severity of both pathogenic fungi infections. Collectively, our results suggest that ulvans induce resistance against both fungal pathogens independently of its sulfation degree. [ABSTRACT FROM AUTHOR]

Fungal pathogens caused various diseases which resulted in heavy yield and quality losses on plants of commercial interests such as fruits, vegetables, and flowers. In our preliminary experimental results, the methanol extracts of four species of medicinal plants Melaphis chinensis, Eugenia caryophyllata, Polygonum cuspidatum, and Rheum officinale possessed antifungal activity to causal agent of cabbage anthracnose, Colletotrichum higginsianum. Thus it was conducted to identify and quantify the chemical constituents in these herbs and to assess the antifungal effects of these compounds. Among the tested principles, the indicator compound methyl gallate from M. chinensis was the most effective one against the conidial germination. In addition, it exhibited significant effects of controlling anthracnose disease of Chinese cabbage caused by C. higginsianum PA-01 in growth chamber. These results indicate that M. chinensis may be potential for further development of plant-derived pesticides for control of anthracnose of cabbage and other cruciferous crops. [ABSTRACT FROM AUTHOR]

• CsAtf1 affects the regulation of fludioxonil resistance. • CsAtf1 deletion attenuates the virulence of C. siamense. • CsAtf1 deletion mutants showed slightly retarded mycelial growth, small conidia, slow spore germination, and abnormal appressorium formation. In phytopathogenic fungi, the HOG MAPK pathway has roles in osmoregulation, fungicide sensitivity, and other processes. The ATF1/CREB-activating transcription factor Atf1 is a regulator that functions downstream of the HOG MAPK pathway. Here, we identified a gene, designated CsAtf1 , that encodes a bZIP transcription factor in Colletotrichum siamense , which is the main pathogen that causes Colletotrichum leaf fall disease in rubber trees in China. CsAtf1 localizes to the nucleus. Its mRNA expression correlates positively with that of CsPbs2 and CsHog1 in the HOG MAPK pathway in response to activator (anisomycin), inhibitor (SB203580) and fludioxonil treatments. The CsAtf1 deletion mutant showed slightly retarded mycelial growth, small conidia, slow spore germination, and abnormal appressorium formation. This mutant showed the increased spore germination rate after fludioxonil treatment and more resistance to the fungicide fludioxonil than did the wild-type fungus. However, unlike deletion of Pbs2 or Hog1 , which resulted in greater sensitivity to osmotic stress, the CsAtf1 deletion induced slightly increased resistance to osmotic stress and the cell wall stress response. The ΔCsAtf1 strain also exhibited significantly reduced virulence on rubber tree leaves. These data revealed that CsAtf1 plays a key role in the regulation of fludioxonil sensitivity and in pathogenicity regulation in C. siamense. [ABSTRACT FROM AUTHOR]