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Pesticide Biochemistry and Physiology Nov 2022Gray blight caused by Pestalotiopsis-like species is a major disease of tea crop worldwide including India, causes significant losses in tea production. Management of...
Gray blight caused by Pestalotiopsis-like species is a major disease of tea crop worldwide including India, causes significant losses in tea production. Management of disease using fungal biocontrol agents is considered an alternative eco-friendly approach to synthetic fungicides. The present study explores the efficacy of Trichoderma reesei in the gray blight management in tea crop and activation of defense related enzymes against gray blight pathogen by developing a tri-trophic interaction system. Out of 16 isolates of Trichoderma species screened in laboratory against Pseudopestalotiopsis theae, a gray blight pathogen, isolate TRPATH01 had highest antagonistic activity (81.2%) against Ps. theae and was found to produce inhibitory volatile and non-volatile metabolites. Based on ITS and TEF-1 alpha sequencing, the isolate TRPATH01 was recognised as T. reesei. The methanolic extract of T. reesei was also found effective against Ps. theae at 200 μg/mL also confirmed presence of highest volatile compounds. The isolate also produced hydrolytic enzymes such as chitinase, cellulase, protease, and lipase. Under nursery conditions, 2% and 5% concentrations with 2 × 10 conidia/ml of T. reesei were able to reduce 67.5% to 75.0% of disease severity over pathogen inoculated controls. Moreover, compared with positive and negative controls, T. reesei -treated tea plants showed increased shoot height, stem diameter, shoot and root fresh weight at 45 days after inoculation. Principal component analysis capturing 97.1% phenotypic variations, which revealed that the tea plants co-inoculated with Ps. theae and T. reesei exhibited significantly upregulated accumulation of defensive enzymes viz., polyphenol oxidase, peroxidase, phenylalanine ammonia lyase, phenolics, β-1, 3-glucanase, and chitinase when compared to both controls. Hence, T. reesei could provide an eco-friendly and viable mitigation option for gray blight in tea gardens by inducing defense-related enzymes.
Topics: Hypocreales; Camellia sinensis; Chitinases; Tea
PubMed: 36464383
DOI: 10.1016/j.pestbp.2022.105279 -
Molecules (Basel, Switzerland) Nov 2022species have gained attention thanks to their structurally complex and biologically active secondary metabolites. In past decades, several new secondary metabolites... (Review)
Review
species have gained attention thanks to their structurally complex and biologically active secondary metabolites. In past decades, several new secondary metabolites were isolated and identified. Their bioactivities were tested, including anticancer, antifungal, antibacterial, and nematicidal activity. Since the previous review published in 2014, new secondary metabolites were isolated and identified from species and unidentified strains. This review gathered published articles from 2014 to 2021 and focused on 239 new secondary metabolites and their bioactivities. To date, 384 species have been discovered in diverse ecological habitats, with the majority of them unstudied. Some may contain secondary metabolites with unique bioactivities that might benefit pharmacology.
Topics: Pestalotiopsis; Antifungal Agents; Ecosystem
PubMed: 36432188
DOI: 10.3390/molecules27228088 -
Frontiers in Microbiology 2022is an important wood for commercial products especially pulp and medium-density fibreboard. However, it is susceptible to infection, leading to Ceratocystis wilt....
is an important wood for commercial products especially pulp and medium-density fibreboard. However, it is susceptible to infection, leading to Ceratocystis wilt. Therefore, the present work aimed to (i) establish the diversity of endophytic fungi in different plant parts of ,and (ii) evaluate the antifungal potentials of the isolated and identified endophytic fungi against . Endophytic fungal identification was conducted by PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) and ITS4 regions of nuclear ribosomal DNA. A total of 66 endophytic fungi were successfully isolated from different parts of ; leaf (21), stem (13), petiole (12), root (9), flower (6), and fruit (5). The endophytic fungal isolates belonged to Ascomycota (95.5%) and Zygomycota (4.5%). For Ascomycota 13 genera were identified: (28.6%), (28.6%), (12.7%), (9.5%), (6.3%), (3%), and , , , , , , and each with a single isolate. For Zygomycota, only sp. (5%) was isolated. Against , (AC 1S) from stem, (AC 7L) from leaf, (AC 3F) from the flower, sp. (AC 2 U) from fruit, (AC 4P) from petiole, and sp. (AC 9R) from root exhibited strong inhibition for between 58.33 to 69.23%. Thus, it can be concluded that certain endophytic fungi of have the potential to be harnessed as anti-Ceratocystis agent in future biotechnological applications.
PubMed: 36425026
DOI: 10.3389/fmicb.2022.887880 -
Microorganisms Nov 2022In the present work, research tasks were carried out in the search for fungi with potential biocontrol possibilities in relation to the ash dieback pathogen, . In the...
In the present work, research tasks were carried out in the search for fungi with potential biocontrol possibilities in relation to the ash dieback pathogen, . In the years 2012-2021, dead petioles of and were collected, on which morphological structures of showed unusual symptoms of dying (apothecia) and signs of colonization by other fungi (pseudosclerotial plates). Based on morphological and molecular phylogenetic data, 18 fungal taxa were identified. Thirteen of them belong to Ascomycota: , , sp., sp., , sp., sp., , , , , , sp., and five other taxa are represented by Basidiomycota: sp., , sp., sp. and sp. In 108 dual cultures in vitro, three different types of interactions were distinguished: (i) physical colony contact (5.6%), (ii) presence of an inhibition zone between the colonies (0.9%), and (iii) copartner overgrowth of colonies and partial or complete replacement of the pathogen (93.5%). In the dual cultures, various morphological deformations of hyphae were observed: the development of apical or intercalary cytoplasmic extrusions, development of internal hyphae of the test fungi in pathogens' hyphae, the deformation and disruption of significant sections of hyphae via lysis and mycoparasitism, complete desolation of cells and breakdown of hyphae into short fragments, and disappearing of pigment in the affected hyphae of . The inoculation tests performed in vivo or in glass Petrie dishes showed that all the identified taxa were able to lead to pathological changes in apothecia, and the mycelium of some of them completely covered pseudosclerotial plates of . It was emphasized in the discussion that such activity of these fungi in forest stands may contribute to the reduction in the inoculum reservoir.
PubMed: 36422320
DOI: 10.3390/microorganisms10112250 -
Journal of Fungi (Basel, Switzerland) Nov 2022Pepper leaf spot is a common disease of . When it is serious, it directly affects the growth of , making the plant unable to blossom and bear fruit, which seriously...
Pepper leaf spot is a common disease of . When it is serious, it directly affects the growth of , making the plant unable to blossom and bear fruit, which seriously restricts the development of the industry. Therefore, the pathogenic mechanism of leaf spots should be explored to provide a basis for a comprehensive understanding of the disease. Using liquid chromatography-mass spectrometry (LC-MS) technology combined with the data-dependent acquisition, the full spectrum analysis of pathogen mycelium samples was carried out. Partial least squares discriminant analysis (PLS-DA) was used to reveal the differences in metabolic patterns among different groups. Hierarchical clustering analysis (HCA) and PLS-DA were used to reveal the relationship between samples and metabolites, which reflected the metabolomics changes of in the logarithmic growth phase of mycelia, the stable growth phase of mycelia, the massive spore stage, the induction culture conditions of PDA and leaves, and the possible pathogenic substances were selected for pathogenicity detection. PLS-DA had a strong predictive ability, indicating a clear analysis trend between different groups. The results of the metabolomics analysis showed that the differential metabolites of pathogenic bacteria were abundant at different stages and under different medium conditions, and the content of metabolites changed significantly. There were 3922 differential metabolites in nine groups under positive and negative ion modes, including lipids and lipid molecules, organic acids and their derivatives, organic heterocyclic compounds, organic oxygen compounds, carbohydrate polyketides, nucleosides, nucleotides, and analogs. The results of the pathogenicity test showed that the leaves treated with 3,5-dimethoxy benzoic acid, -(5-adenosy)-l-homocysteine, 2-(1-indol-3-yl) acetic acid, l-glutamic acid, and 2-(2-acetyl-3,5-dihydroxy phenyl) acetic acid showed different degrees of yellowish-brown lesions. This indicated that these substances may be related to the pathogenicity of , and the incidence was more serious when treated with 3,5-dimethoxybenzoic acid and -(5-adenosy)- l -homocysteine. This study provides a basis for further analysis of differential metabolites and provides a theoretical reference for the prevention and treatment of leaf spot.
PubMed: 36422029
DOI: 10.3390/jof8111208 -
Marine Drugs Nov 2022Five undescribed polyketide derivatives, pestaloketides A-E (-), along with eleven known analogues (-), were isolated from the sponge-derived fungus sp. Their...
Five undescribed polyketide derivatives, pestaloketides A-E (-), along with eleven known analogues (-), were isolated from the sponge-derived fungus sp. Their structures, including absolute configurations, were elucidated by analyses of NMR spectroscopic HRESIMS data and electronic circular dichroism (ECD) calculations. Compounds , , , and exhibited weak cytotoxicities against four human cancer cell lines, with IC values ranging from 22.1 to 100 μM. Pestaloketide A () is an unusual polyketide, featuring a rare 5/10/5-fused ring system. Pestaloketides A () and B () exhibited moderately inhibited LPS-induced NO production activity, with IC values of 23.6 and 14.5 μM, respectively, without cytotoxicity observed. Preliminary bioactivity evaluations and molecular docking analysis indicated that pestaloketides A () and B () had the potential to be developed into anti-inflammatory activity drug leads.
Topics: Humans; Polyketides; Pestalotiopsis; Molecular Docking Simulation; Fungi; Anti-Inflammatory Agents
PubMed: 36421989
DOI: 10.3390/md20110711 -
FEMS Microbiology Letters Dec 2022Terrestrial leaf litter is an essential energy source in forest streams and in many tropical streams, including Cerrado, litter undergoes biological decomposition mainly...
Terrestrial leaf litter is an essential energy source in forest streams and in many tropical streams, including Cerrado, litter undergoes biological decomposition mainly by fungi. However, there is a limited understanding of the contribution of isolated fungal species to in-stream litter decomposition in the tropics. Here we set a full factorial microcosms experiment using four fungal species (Aquanectria penicillioides, Lunulospora curvula, Pestalotiopsis submerses, and Pestalotiopsis sp.) incubated in isolation, two litter types (rapid and slow decomposing litter) and two nutrient levels (natural and enriched), all characteristics of Cerrado streams, to elucidate the role of isolated fungal species on litter decomposition. We found that all fungal species promoted litter mass loss but with contributions that varied from 1% to 8% of the initial mass. The fungal species decomposed 1.5 times more the slow decomposing litter and water nutrient enrichment had no effect on their contribution to mass loss. In contrast, fungal biomass was reduced by nutrient enrichment and was different among fungal species. We showed fungal contribution to decomposition depends on fungal identity and litter type, but not on water nutrients. These findings suggest that the identity of fungal species and litter types may have more important repercussions to in-stream decomposition than moderate nutrient enrichment in the tropics.
Topics: Water; Biomass
PubMed: 36416839
DOI: 10.1093/femsle/fnac113 -
Frontiers in Plant Science 2022Productivity decline of plantation and difficulty in natural regeneration remains a serious problem because of allelopathy. Previous studies have confirmed that...
Productivity decline of plantation and difficulty in natural regeneration remains a serious problem because of allelopathy. Previous studies have confirmed that 2,4-di-tert-butylphenol (2,4-DTBP) are the major allelochemicals of the litter exudates. The production of these allelochemicals may derive from decomposition of litter or from the litter endophyte and microorganisms adhering to litter surfaces. In the present study, we aimed to evaluate the correlation between allelochemicals in litter and endophytic and epiphytic fungi and bacteria from litter. A total of 100 fungi and 116 bacteria were isolated from the interior and surface of litter of different forest ages (young, half-mature, and mature plantation). Results showed that the fermentation broth of fungal genera sp. and sp., and bacterial genera , , and had the strongest allelopathic effect on seeds. Allelochemicals, such as 2,4-DTBP and its analogs were identified in the fermentation broths of these microorganisms using GC/MS analysis. These results indicate that endophytic and epiphytic fungi and bacteria in litters are involved in the synthesis of allelochemicals of . To further determine the abundance of the allelopathic fungi and bacteria, Illumina MiSeq high-throughput sequencing was performed. The results showed that bacterial genera with strong allelopathic potential were mainly distributed in the young and half-mature plantation with low abundance, while the abundance of fungal genera sp. and sp. were higher in the young and mature plantations. In particular, the abundance of sp. in the young and mature plantations were 501.20% and 192.63% higher than in the half-mature plantation, respectively. Overall, our study demonstrates that the litter fungi with higher abundance in the young and mature plantation were involved in the synthesis of the allelochemical 2,4-DTBP of This finding may be important for understanding the relationship between autotoxicity and microorganism and clarifying the natural regeneration problem of
PubMed: 36407626
DOI: 10.3389/fpls.2022.1022984 -
TheScientificWorldJournal 2022This study was conducted to isolate and identify the endophytic fungi from the bark and leaves of the plant and investigate the pharmacological activities of endophytic...
This study was conducted to isolate and identify the endophytic fungi from the bark and leaves of the plant and investigate the pharmacological activities of endophytic fungi along with plant parts. After isolation, endophytic fungi were identified based on morphological characteristics and molecular identification. Antimicrobial, antioxidant, and cytotoxic activities were studied by a disc diffusion method, free radical scavenging DPPH assay, and brine shrimp lethality bioassay, respectively. A total of eight endophytic fungi were isolated and identified up to the genus level based on morphological characteristics and confirmed by molecular identification techniques. Among the eight isolates, three isolates were identified as sp. (SCBE-2, SCBE-7, and SCLE-9), while the rest of the isolates belonged to sp. (SCBE-1), sp. (SCBE-3), sp. (SCBE-4), sp. (SCLE-7), and sp. (SCLE-8). The presence of flavonoids, anthraquinones, coumarins, and isocoumarins was assumed by the preliminary screening of the fungal and plant extracts by a thin-layer chromatographic technique under UV light. Fungal extracts of sp. sp. were found sensitive to all test bacteria, but only extracts from the leaf and bark showed significant antifungal activity along with their antimicrobial activity. sp. The fungal extract showed the highest free radical scavenging activity (2.43 g/mL) near that of ascorbic acid (2.42 g/mL). Some fungal extracts showed cytotoxic activity that, in general, suggests their probable abundance of biological metabolites. This is the first approach to investigate the endophytic fungi of Linn. in Bangladesh, to find the pharmacological potential of endophytes, and to explore novel compounds from those endophytes.
Topics: Syzygium; Fungi; Endophytes; Anti-Infective Agents; Free Radicals
PubMed: 36393829
DOI: 10.1155/2022/9529665 -
Plant Disease May 2023A new sp. was recently reported causing outbreaks of leaf spot and fruit rot on strawberry in Florida, Georgia, and South Carolina. In contrast to other pathogens, the...
A new sp. was recently reported causing outbreaks of leaf spot and fruit rot on strawberry in Florida, Georgia, and South Carolina. In contrast to other pathogens, the new species appears more aggressive and destructive on strawberry. Current chemical options for management are disease suppressive at best, and affected growers have been experiencing major yield losses. In this study, we developed a molecular method based on polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) for identification of the new sp. from strawberry. Isolates of the new sp. collected in Florida; isolates of , , , , , and ; and isolates from South Carolina suspected to be the new sp. were included in this study. This method is based on PCR amplification of a β-tubulin gene fragment using a previously published set of primers (Bt2a and Bt2b), followed by use of the restriction enzyme BsaWI. The enzyme cuts the PCR product from the new sp. twice, yielding fragments of 290 base pairs (bp) and 130 and 20 bp in size, whereas fragments from other species are only cut once, yielding fragments of 420 and 20 bp. This method will aid research labs and diagnostic clinics in the accurate and fast identification of the aggressive sp. variant from strawberry.
Topics: Fragaria; Polymorphism, Restriction Fragment Length; Xylariales; Polymerase Chain Reaction; Florida
PubMed: 36383989
DOI: 10.1094/PDIS-09-22-2117-RE