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Antifungal Activity of Oleoresin and Fractions of Pinus elliottii Engelm and Pinus tropicalis against Phytopathogens
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作者 Gessica Andrade Fariza Abrao +5 位作者 Patrick Silva Sergio Ricardo Ambrosio Rodrigo Cassio Sola Veneziani Wilson Roberto Cunha Regina Helena Pires Carlos Henrique G.Martins 《American Journal of Plant Sciences》 2014年第26期3898-3903,共6页
Microorganism resistance to the existing products is yet another difficulty that agriculturalists have to deal with. In this context, the search for new agricultural products that can fight phytopathogens has become i... Microorganism resistance to the existing products is yet another difficulty that agriculturalists have to deal with. In this context, the search for new agricultural products that can fight phytopathogens has become increasingly important. Plants have played an important role in this process, because they can serve as a source of new compounds for drug discovery. Plants belonging to the genus Pinus produce an oleoresin that protects the plant against herbivores and pathogens. With a view to developing products that can combat fungal pathogens without harming the environment, this work aimed to evaluate the antifungal activity of the oleoresins and fractions of Pinus elliottii Engelm and Pinus tropicalis against phytopathogens. The methodology based on NCCLS M38-A standards aided antifungal activity assessment. The microdilution method helped to determine the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC). The oleoresins of P. elliottii and P. tropicalis afforded the most significant results—they displayed fungicidal activity against all the tested species. MIC values were promising, especially the MIC of the oleoresin of P. elliottii against S. rolfsii (1.95 μg·mL-1). The MIC values of the oleoresins of P. elliottii and P. tropicalis ranged from 1.95 to 1000 μg·mL-1 and from 31.25 to 250 μg·mL-1, respectively. Fraction PT2 of P. tropicalis furnished the best results among all the assayed fractions: MIC values lay between 125 and 500 μg·mL-11. In conclusion, the oleoresin of P. tropicalis is a promising source of new antifungal agents for application in the treatment of phytopathogenic infections. 展开更多
关键词 Pinus elliottii Pinus tropicalis phytopathogens Antifungal Activity OLEORESIN
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Bioactive Compounds Recovery from Larrea tridentata by Green Ultrasound- Assisted Extraction
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作者 Muyideen Olaitan Bamidele Jose Sandoval-Cortes +3 位作者 Maria Liliana Flores-Lopez Olga Berenice Alvarez Perez Monica Lizeth Chavez Gonzalez Cristobal Noe Aguilar 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期3091-3107,共17页
Postharvest losses remain a significant challenge,particularly in developing countries that have inadequate infra-structure.Medicinal plants offer an eco-friendly and sustainable solution for managing diseases and pest... Postharvest losses remain a significant challenge,particularly in developing countries that have inadequate infra-structure.Medicinal plants offer an eco-friendly and sustainable solution for managing diseases and pests in agri-cultural systems.These plants are rich in bioactive compounds,such as alkaloids,flavonoids,terpenoids,phenolics,and essential oils,many of which have proven antimicrobial,antifungal,insecticidal,and antioxidant properties.These characteristics make medicinal plants viable candidates for postharvest disease and pest control.Among these,Larrea tridentata(creosote bush)is particularly notable for its bioactive compounds with strong antifungal properties.Their potential applications include agriculture,food preservation,and medicine.This study aimed to evaluate how different solvent mixtures affect the efficiency of ultrasound-assisted extraction,total polyphenol content,antioxidant capacity,and antifungal activity of L.tridentata leaves and stems.Thefindings revealed that the 60%ethanol ultrasound-assisted extract of L.tridentata leaves(ULL 60%)contained the highest concentration of bioactive compounds,including hydrolysable tannins(690.2 mg GAE/100 g)and condensed tan-nins(329.9 mg CE/100 g).All extracts demonstrated notable antioxidant activity in ABTS,DPPH,and FRAP assays,with ethanol-based extracts showing greater antioxidant potential than their aqueous counterparts.In terms of antifungal efficacy,100%ethanol leaf extract exhibited the strongest inhibition against Fusarium oxyspor-um(60.03%),whereas 50%ethanol extract effectively inhibited Alternaria alternata(53.61%).Six major polyphe-nolic compounds were identified using reverse-phase high-performance liquid chromatography coupled with electrospray ionization mass spectrometry(RP-HPLC-ESI-MS).These include quercetin,luteolin,3,4-dihydrox-yphenylethanol,elenolic acid,nordihydroguaiaretic acid(NDGA),and kaempferide.These compounds are known to have antibacterial,antifungal and antioxidant properties.Thesefindings underscore the potent fungi-static properties of L.tridentata leaf extracts against key phytopathogenic fungi,highlighting their potential as bioactive agents in the formulation of eco-friendly biopesticides. 展开更多
关键词 phytopathogens bioactive compounds desert plants Fusarium oxysporum Alternaria alternata
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Phytochemical Analysis and Antifungal Activity of Extracts from Leaves and Fruit Residues of Brazilian Savanna Plants Aiming Its Use as Safe Fungicides 被引量:1
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作者 Caroline Alves Breda Alessandra Marcon Gasperini +4 位作者 Vera Lucia Garcia Karin Maia Monteiro Giovana Anceski Bataglion Marcos Nogueira Eberlin Marta Cristina Teixeira Duarte 《Natural Products and Bioprospecting》 CAS 2016年第4期195-204,共10页
The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity.In this study,ethanolic extracts from leave... The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity.In this study,ethanolic extracts from leaves and fruit residues(peel and seeds)of three Brazilian savanna species(Acrocomia aculeata,Campomanesia adamantium and Caryocar brasiliense)were evaluated against phytopathogenic fungi.Additionally,the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated.Extracts from C.brasiliense(pequi)peel and leaves were active against Alternaria alternata,Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 lg/mL.When incorporated in solid media,these extracts extended the lag phase of A.alternata and A.solani and reduced the growth rate of A.solani.Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid,quinic acid,ellagic acid,glucogalin and corilagin.The oral acute toxicity was relatively low,being considered safe for use as a potential natural fungicide. 展开更多
关键词 Brazilian savanna fruits RESIDUES Natural fungicides phytopathogens
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Behavior of the Fungus <i>Colletotrichum gloeosporioides</i>(Penz &Sacc.), Which Causes Bitter Rot in Apples after Harvesting
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作者 Sideney Becker Onofre Dirlane Antoniazzi 《Advances in Microbiology》 2014年第4期202-206,共5页
The apple is the second most important fruit in Brazil. However, apple cultivars are susceptible to several diseases that can cause losses after harvesting. Bitter rot is caused by the fungus Colletotrichum gloeospori... The apple is the second most important fruit in Brazil. However, apple cultivars are susceptible to several diseases that can cause losses after harvesting. Bitter rot is caused by the fungus Colletotrichum gloeosporioides and is one of the most damaging summer diseases. The goal of this work was to evaluate the behavior of this fungus in four apple cultivars grown in Brazil (Fuji, Gala, Golden and Green) under two treatments: direct inoculation and isolated fungus. The fungus was isolated by taking fragments from infected fruits, which were stored on Potato Dextrose Agar (PDA) in a laboratory. For the direct treatment, the fungus was removed from infected fruits and directly inoculated into healthy fruits. After inoculation, the fruits were kept at room temperature and the halos of degradation were evaluated every 48 hours. The results demonstrated that direct inoculation was more pathogenic, that the Gala cultivar was the most resistant to the pathogen, and that the Golden cultivar was the most susceptible. 展开更多
关键词 Diseases Biotechnology phytopathogens FUNGI Pathology
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Recent Achievements in the Bio-control of Orobanche Infesting Important Crops in the Mediterranean Basin 被引量:5
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作者 A. Evidente M. A. Abouzeid +1 位作者 A. Andolfi A. Cimmino 《Journal of Agricultural Science and Technology(A)》 2011年第4X期461-483,共23页
Orobanche spp. (broomrapes) are holoparasitic plants distributed predominantly in the Northern Hemisphere parasitizing the roots of a range of plant species mainly in wild ecosystems. Orobanche species cause severe ... Orobanche spp. (broomrapes) are holoparasitic plants distributed predominantly in the Northern Hemisphere parasitizing the roots of a range of plant species mainly in wild ecosystems. Orobanche species cause severe yield reduction of many important crops. There are only very few herbicides which are able to selectively control broomrapes and different approaches have been put forward to develop natural product based pesticides to control Orobanche. Several phytopathogenic fungi were evaluated for their use as potential mycoherbicide and for ability to produce toxic metabolites which could be applied as herbicides. Using the alternative approach "suicidal germination", interesting results were obtained by testing two microbial metabolites (fusicoccins and ophiobolin A) especially with Orobanche species whose germination is not induced by the synthetic strigolactone GR24. From pea root exudates, peagol and peagoldione, close related to strigolactones, and three polyphenols, named peapolyphenols A-C, together with already well known polyphenol and a chalcone, were isolated. They showed a selective stimulation of Orobanche seed germination with the last two and peapolyphenol A showing a specific stimulatory activity on O. foetida. This review describes the most recent results achieved on Orobanche bio-control, mainly focusing on those regarding O. ramosa, O. crenata and O. foetida. 展开更多
关键词 BROOMRAPE O. crenata O. ramosa biological control phytopathogenic fungi phytotoxic metabolites suicidal seedgermination.
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<i>Bacillus subtilis Strains</i>with Antifungal Activity against the Phytopathogenic Fungi 被引量:2
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作者 Ayslu Mirkasimovna Mardanova Guzel Fanisovna Hadieva +5 位作者 Marat Tafkilevich Lutfullin Irina Valer’evna Khilyas Leyla Farvazovna Minnullina Adelya Gadelevna Gilyazeva Lidiya Mikhailovna Bogomolnaya Margarita Rashidovna Sharipova 《Agricultural Sciences》 2017年第1期1-20,共20页
Bacillus strains isolated from the rhizosphere soil of potato roots were evaluated for the potential antagonistic activity against fungal pathogens in vitro and in vivo. Two bacterial isolates were identified as new B... Bacillus strains isolated from the rhizosphere soil of potato roots were evaluated for the potential antagonistic activity against fungal pathogens in vitro and in vivo. Two bacterial isolates were identified as new Bacillus subtilis strains by 16S rRNA and GyrB gene sequencing and were designated GM2 and GM5, respectively. Strains were characterized by their ability to inhibit growth of a number of phytopathogenic fungi. It was shown that GM5 strain inhibited growth of phytopathogenic fungi more effectively than GM2 strain. Both strains were capable of producing a number of hydrolytic enzymes as well as antimicrobial metabolites (ammonia and HCN). In addition, GM2 strain also produced siderophores. Four genes encoding antimicrobial peptides were identified in the genome of GM2 strain: ituC, bmyB, bacA and srfA. Genome of GM5 contained two genes encoding for antimicrobial peptides, srfA and fenD. Purified lipopeptide fraction from GM5 but not from GM2 strain was able to control Fusarium solani spread in the plate assay. Furthermore, Bacillus subtilis strain GM2 promoted growth of wheat but only GM5 strain was able to protect wheat seedlings from Fusarium oxysporum infection. 展开更多
关键词 Bacillus SUBTILIS FUSARIUM Phytopathogenic Fungi ANTAGONISTIC Activity Antimicrobial Peptides
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Antifungalmycin,an antifungal macrolide from Streptomyces padanus 702 被引量:1
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作者 Yi-Fen WANG Sai-Jin WEI +2 位作者 Zhi-Ping ZHANG Tong-He ZHAN Guo-Quan TU 《Natural Products and Bioprospecting》 CAS 2012年第1期41-45,共5页
Two polyene macrolide antibiotics:antifungalmycin(1)and fungichromin(2)were isolated from the culture mycelia of Streptomyces padanus 702 via bioactivity-guided fractionation using various chromatographic procedures.T... Two polyene macrolide antibiotics:antifungalmycin(1)and fungichromin(2)were isolated from the culture mycelia of Streptomyces padanus 702 via bioactivity-guided fractionation using various chromatographic procedures.Their structures were elucidated on the basis of spectral analysis,and 1 is a new polyene macrolide.Compounds 1 and 2 showed significant inhibition against Gibberella zeae with EC_(50)values of 26.71 and 2.21μg/mL,Fusicoccum sp.(plantain head blight)with EC_(50)values of 23.4 and 3.17μg/mL,Mucor ssp.8894 with EC_(50)values of 28.80 and 2.11μg/mL,Ustilaginoidea virens with EC_(50)values of 26.72 and 0.21μg/mL,respectively.This shows that the microbial secondary metabolites 1 and 2 have the potential to be developed as agricultural fungicides for use against G.zeae,Fusicoccum sp.,Mucor ssp.8894,and U.virens. 展开更多
关键词 antifungalmycin Streptomyces padanus 702 polyene macrolide BIOCONTROL antifungal activity PHYTOPATHOGEN
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PCR-Mediated Detection of Endophytic and Phytopathogenic Fungi from Needles of the Japanese Black Pine, <i>Pinus thunbergii</i> 被引量:1
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作者 Junichi Kihara Makoto Ueno Sakae Arase 《Open Journal of Forestry》 2015年第4期431-442,共12页
A specific and sensitive polymerase chain reaction (PCR) assay based on the internal transcribed spacer (ITS) region of rDNA sequences was developed to detect endophytic and phytopathogenic fungi from needles of the J... A specific and sensitive polymerase chain reaction (PCR) assay based on the internal transcribed spacer (ITS) region of rDNA sequences was developed to detect endophytic and phytopathogenic fungi from needles of the Japanese black pine, Pinus thunbergii. Sequences of the ITS regions of Lophodermium conigenum, Lecanosticta acicola, Pestalotiopsis neglecta, Rhizosphaera kalkhoffii, and Septorioides pini-thunbergii were compared, and each specific primer pair for these species was designed. First, the designed primer pairs were tested for their specificity to detect each species. A PCR product was amplified only each combination of species and its specific primer pair, confirming the specificity of the designed primer pairs. These primer pairs were also tested on DNA extracted from the needles of P. thunbergii. The PCR products were amplified not only in needles with lesions but also in healthy needles without symptoms. Furthermore, several endophytic and phytopathogenic fungi could be simultaneously detected from the same region in a needle. The PCR-mediated detection method developed in this study will be a valuable tool for the detection of the endophytic and phytopathogenic fungi, not only as a rapid diagnostic tool for early detection but also for monitoring variations in both the quality and quantity of the endophytic and phytopathogenic fungi in needles in Japanese black pines. 展开更多
关键词 Phytopathogenic FUNGI ENDOPHYTIC FUNGI Pinus thunbergii JAPANESE Black Pine PCR-Mediated Detection
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Isolation and Screening of Silicate Bacteria from Various Habitats for Biological Control of Phytopathogenic Fungi
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作者 Zakira Naureen Muhammad Aqeel +5 位作者 Muhammad Nadeem Hassan Syed Abdullah Gilani Nahla Bouqellah Fazal Mabood Javid Hussain Fauzia Y. Hafeez 《American Journal of Plant Sciences》 2015年第18期2850-2859,共10页
Silicate solubilizing bacteria (SSB) can play an efficient role in soil by solubilizing insoluble forms of silicates. In addition to this some SSB can also solubilize potassium and phosphates, hence increasing soil fe... Silicate solubilizing bacteria (SSB) can play an efficient role in soil by solubilizing insoluble forms of silicates. In addition to this some SSB can also solubilize potassium and phosphates, hence increasing soil fertility and enhancing plant defense mechanisms. A total of 111 bacterial strains were isolated from various habitats of Pakistan and screened for solubilization of silicate, phosphate and potassium on respective media. Out of these, 35 bacterial isolates were capable of solubilizing either silicate, phosphate or potassium. Amongst these 7 bacterial isolates were capable of solubilizing all three minerals tested. The highest silicate (zone diameter 54 mm) and phosphate solubilization (zone diameter 55 mm) was observed for bacterial isolate NR-2 while the highest potassium solubilization was observed for NE-4b (zone diameter 11 mm). Dual culture antagonistic assays were carried out by using these bacterial isolates against four plant pathogenic fungi Magnaporthae grisae, Rhizoctonia solani, Altarnaria alternata and Macrophomina pheasolina. Mean zone of inhibition of these bacterial isolates against the four pathogenic fungi ranged between 4 mm to 39 mm. The largest zone of inhibition against all four bacterial strains was recorded for bacterial isolate NR-2 followed by NE-4b. These strains will be further investigated for their plant growth promoting activities in the future. 展开更多
关键词 SILICATE Solubilizing BACTERIA BIOCONTROL Phytopathogenic FUNGI
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Analogs of Antifungal Indoles Isolated from Aporpium Caryae with Activity Against Sudden-Death Syndrome of Soybean
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作者 Brenda Bertinetti Mercedes Scandiani Gabriela Cabrera 《American Journal of Plant Sciences》 2011年第2期245-254,共10页
Based on the precedent discovery of a weak antifungal indole isolated from Aporpium caryae, which increased its activity when changing the N-alkyl chain, nineteen N-alkyl indoles, with alkyl chains from one to ten car... Based on the precedent discovery of a weak antifungal indole isolated from Aporpium caryae, which increased its activity when changing the N-alkyl chain, nineteen N-alkyl indoles, with alkyl chains from one to ten carbons and one or two hydroxyls, one amine or bromine functional groups, were prepared and fully characterized by spectroscopic methods. The aim of this study is the search for new synthetic agrochemical leads derived from natural products. The antifungal activity of the synthesized compounds against three fungal strains was measured in vitro. Six compounds presented good activity against Fusarium virguliforme, the causal agent of sudden-death syndrome (SDS) in soybean, in a bioautography assay. Four of them were tested in a germination test and in a greenhouse experiment. All tested compounds, applied as seed treatment, showed antifungal properties being effective to control SDS when there was low level of fungal contamination. Results indicate that some of the tested compounds are acting as growth inhibitors and represent new leads for the treatment of SDS for which no specific treatment has been previously reported. 展开更多
关键词 N-Alkyl INDOLE SOYBEAN PHYTOPATHOGEN Fusarium Virguliforme Sudden-Death SYNDROME
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Effect of 4% glycerol and low aeration on result of expression in <i>Escherichia coli</i>of Cin3 and three <i>Venturia inaequalis</i>EST’s recombinant proteins
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作者 Taha H. Al-Samarrai William T. Jones +2 位作者 Dawn Harvey Christopher A. Kirk M. Templtone 《American Journal of Molecular Biology》 2013年第1期1-9,共9页
The phytopathogenic fungus Venturia inaequalis causes scab of apple. Once this fungus penetrates the plant surface, it forms a specialized body called a stroma between the inner cuticle surface and the epidermal cell ... The phytopathogenic fungus Venturia inaequalis causes scab of apple. Once this fungus penetrates the plant surface, it forms a specialized body called a stroma between the inner cuticle surface and the epidermal cell wall. A novel Venturia inaequalis 5704 (Cin3) and three expressed sequence tags (ESTs);38, 6987, and 4010 are strongly up-regulated in the early stages of infection. The CIN3 and three ESTs using two vectors pMAL-c2 and pET 21 were expressed in Escherichia coli. Recombinant proteins expression, solubility and yields were analyzed. 38, 5704 (Cin3) and 6987 re- combinant proteins were expressed in soluble form and while 4010 was expressed in inclusion bodies. Re- solution on native-PAGE, the recombinant proteins;38, 5704 (Cin3), 6987 were shown to be present in dimmer, tetramer and polymer. A method was de- veloped, consisting of induction of expression at va- rious temperatures, and using enriched broth with 4% glycerol together with slow shaking, led to a decrease in concentration of nascent polypeptide and production of soluble recombinant proteins of;38, 5704 (Cin3), 6987 and 4010. Resolution on native- PAGE, the recombinant proteins were shown to be present as monomer. 展开更多
关键词 Venturia inaequalis Expressed Sequence Tag (ESTs) Phytopathogenic FUNGUS APPRESSORIUM A Stroma
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Antiviral Effect of Ribonuclease from <i>Bacillus pumilus</i>against Phytopathogenic Rna-Viruses
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作者 Margarita Sharipova Annett Rockstroh +5 位作者 Nelly Balaban Ayslu Mardanova Anna Toymentseva Anastasiya Tikhonova Semen Vologin Zenon Stashevsky 《Agricultural Sciences》 2015年第11期1357-1366,共10页
Background: Viruses can cause different diseases in plants. To prevent viral infections, plants are treated with chemical compounds and antiviral agents. Chemical antiviral agents usually have narrow specificity, whic... Background: Viruses can cause different diseases in plants. To prevent viral infections, plants are treated with chemical compounds and antiviral agents. Chemical antiviral agents usually have narrow specificity, which limits their wide application. Alternative antiviral strategy is associated with the use of microbial enzymes, which are less toxic and are readily decomposed without accumulation of harmful substances. The aim of this work is to study the effect of Bacillus pumilus ribonuclease on various phytopathogenic viruses with specific focus on the ability of enzyme to eliminate them from plant explants in vitro. Materials and methods: Extracellular ribonuclease of B. pumilus is tested as an antiviral agent. To study the antiviral effect of RNase, depending on concentration and the time of application several plant-virus model systems are used. Virus detection is conducted by serological testing and RT-PCR. Results: Bacillus pumilus ribonuclease possesses antiviral activity against plant Rna-viruses RCMV (red clover mottle virus), PVX (Potato Virus X) and AMV (Alfalfa Mosaic Virus). The maximum inhibitory effect against actively replicating viruses is observed when plants are treated with the enzyme in the concentration of 100 ug/ml prior to infection. In case of local necrosis ribonuclease in the concentration of 1 ug/ml completely inhibits the development of RCMV virus on bean plants. The enzyme is able to penetrate plants and inhibit the development of viral infection, inhibiting effect for untreated surfaces decreased on average for 20%. It is also found that B. pumilus ribonuclease protects apical explants of sprouts of potato tubers from PVM and PVS viruses. Conclusion: B. pumilus ribonuclease possesses antiviral activity against plant Rna-viruses and produces viruses-free plants in the apical meristem culture. 展开更多
关键词 Bacillus Pumilus RIBONUCLEASE Phytopathogenic Rna-Viruses Inhibition VIRUS-FREE APICAL
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Dispersion of the Bacterium Xylella fastidiosa in Portugal
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作者 Carla Carvalho-Luis JoséManuel Rodrigues Luís M.Martins 《Journal of Agricultural Science and Technology(A)》 2022年第1期35-41,共7页
After the first detection of the gram-negative bacterium,Xylella fastidiosa multiplex in Portugal,in January 2019,a“Demarcated Area”was delimited and an“Action Plan”to control the pathogen has been developed.It is... After the first detection of the gram-negative bacterium,Xylella fastidiosa multiplex in Portugal,in January 2019,a“Demarcated Area”was delimited and an“Action Plan”to control the pathogen has been developed.It is considered one of the greatest threats to plant health worldwide and leads to loss of forests vitality and productivity.The current study was developed till June 2020,with the objective to understand the dimension of the issue worldwide and in Portugal,analyzing the state-of-the-art on the biology,dispersion,symptoms,control and risks associated with this bacterium(Research Phase).In the Prospecting Phase,we collected 5 branches with 5-8 leaves,from the four quadrants of the tree,wrapping and labeling them-so 2,261 samples were collected and sent to the laboratory for analysis.It was possible to determine that the two initial outbreaks were not an isolated case,as 107 additional outbreaks were detected in other places,revealing a much more worrying panorama,requiring further analysis on the real impact of this bacterial strain on the natural environment.By the end of this study the demarcated area covered about 62,000 ha.The most affected species was lavender with 30%of positive outbreaks,followed by gorse with 22%,and rosemary with 11%.Spread of Phillaenus spumarius and X.fastidiosa indicates that insect vector and transport links appear to be dispersal facilitators together with Douro River.As eradication is unfeasible to achieve in the coming years,containment will be the most appropriate strategy. 展开更多
关键词 PHYTOPATHOGEN FOREST plant health xylem-limited BACTERIA Xylella fastidiosa multiplex biotic stressors Demarcated Area
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Identification and Expression of Some Plant Cell Wall-Degrading Enzymes Present in Three Ontogenetics Stages of Thecaphora frezii, a Peanut (<i>Arachis hypogaea</i>L.) Pathogenic Fungus
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作者 Néstor Walter Soria Ana Cristina Figueroa +3 位作者 María Soledad Díaz Valeria Roxana Alasino Pablo Yang Dante Miguel Beltramo 《American Journal of Plant Sciences》 2022年第1期1-22,共22页
Peanuts can be affected by the presence of pathogenic microorganisms. The fungus <i>Thecaphora frezii</i> (<i>T. frezii</i>), which belongs to the taxonomic class Ustilaginomycetes, is the caus... Peanuts can be affected by the presence of pathogenic microorganisms. The fungus <i>Thecaphora frezii</i> (<i>T. frezii</i>), which belongs to the taxonomic class Ustilaginomycetes, is the causal agent of the disease known as “peanut smut”. The life cycle of this fungus includes three stages, namely teliospores, basidiospores and hyphae. In the hyphae stage, infection occurs in the peanut plant, which requires the involvement of some enzymes secreted by the fungus. These include the Plant Cell Wall-Degrading Enzymes (PCWDEs), which degrade various polysaccharides. This study aimed to identify the presence of transcript for enzymes belonging to the PCWDEs from three stages of <i>T. frezii</i>. For this, total RNA was extracted from the three ontogenetic stages of <i>T. frezii</i>. These samples were analyzed using an RNA-Seq approach and some transcripts were quantified using Real Time PCR. The analysis of the data provided by the RNA-Seq of the three <i>T. frezii</i> stages, it was possible to identify some transcripts that could encode enzymes compatible with polysaccharides degradation that are part of the plant cell wall. In <i>T. frezii</i> transcriptome, 40 deduced proteins would be enzymes with functions of PCWDEs were identified. They were divided into 27 glycoside hydrolases;two polysaccharide lyases;three carbohydrate esterases and eight enzymes with auxiliary activities. In addition, the fungal SNF1 gene was identified whose activity could be affected by high glucose level, and indirectly influence the levels of some PCWDEs. The analysis of the PCWDEs could help to understand part of the fungal infection process and possibly find substances that can control its development. 展开更多
关键词 Carbohydrate-Degrading Enzymes Phytopathogenic Fungi Smut Fungi TRANSCRIPTOME Thecaphora frezii
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Plant Diseases in Globally Changing Russian Climate
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作者 Mark Levitin 《Journal of Life Sciences》 2015年第10期476-480,共5页
Across all Russia global climate change is observed. Consequences of climatic changes, undoubtedly, will be reflected in distribution of harmful organisms, their injuriousness and will demand development of new approa... Across all Russia global climate change is observed. Consequences of climatic changes, undoubtedly, will be reflected in distribution of harmful organisms, their injuriousness and will demand development of new approaches in plant protection. Over the last 10 years, the spread of cereal crop diseases in the Northwest Russia has been monitored. The purpose of researches is to find new diseases in the Northwest region of Russia. Disease progression was mainly monitored 3 or 4 times during the growing season, from germination to crop maturity. As a result in this region the new diseases were found. In 2005-2007 the causal agent of yellow leaf spot Pyrenophora tritici-repentis was found on wheat. Fusarium graminearum historically has two areas in Russia: the North Caucasus and the Far East. However, since 2003 F. graminearum appeared on the territory of the North-West of Russia. Septoria tritici became the main pathogen of wheat in the North-Western Region.. In 2013 Ramularia collo-cygni was found in Arkhangelsk region. These observations suggest that global warming of climate leads to an expansion south species pathogen to the north regions of Russia. 展开更多
关键词 Climate change phytopathogenic fungi plant diseases.
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Host Range and Virulence of a Fungal Pathogen for Control of Giant Salvinia (<i>Salvinia molesta</i>)
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作者 Clyde D. Boyette Robert E. Hoagland +3 位作者 Lawrence R. Higgenbotham H. Lynn Walker James A. Young Kenneth C. Stetina 《American Journal of Plant Sciences》 2021年第3期444-454,共11页
A teleomorph of the fungus </span><i><span style="font-family:Verdana;">Botryosphaeria</span></i><span style="font-family:Verdana;"> <i>rhodina</i>&l... A teleomorph of the fungus </span><i><span style="font-family:Verdana;">Botryosphaeria</span></i><span style="font-family:Verdana;"> <i>rhodina</i></span><span style="font-family:""><span style="font-family:Verdana;"> (Berkeley et Curtis) von Arx, (</span><i><span style="font-family:Verdana;">Br</span></i><span style="font-family:Verdana;">) </span></span><span style="font-family:""><span style="font-family:Verdana;">was evaluated as a bioherbicide for control of giant salvinia (</span><i><span style="font-family:Verdana;">Salvinia</span></i> <i><span style="font-family:Verdana;">molesta</span></i><span style="font-family:Verdana;"> D.S. Mitchell) under greenhouse conditions and in small-scale field trials. We found that fungal mycelium was highly infective and could be rapidly produced (48+</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">h) in soy</span><span style="font-family:""> </span><span style="font-family:Verdana;">flour-cornmeal liquid media contained in shake flasks or fermenters. A dew period was not required to achieve infection and mortality</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">of inoculated plants. A surfactant (Silwet L-77, a polyalkyleneoxide modified heptamethyl-trisiloxane) incorporated in the fungal formulation was required for </span><i><span style="font-family:Verdana;">Br</span></i><span style="font-family:Verdana;"> to infect and kill plants. Infection and mortality occurred rapidly (within 48 h after treatment), and re-growth of treated plants did not occur. In replicated</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">field trials, </span><i><span style="font-family:Verdana;">Br</span></i><span style="font-family:Verdana;"> controlled giant salvinia ~95%. </span><i><span style="font-family:Verdana;">Br</span></i><span style="font-family:Verdana;"> also infected other plants, such as common salvinia (</span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">minima</span></i><span style="font-family:Verdana;"> Baker), and </span><i><span style="font-family:Verdana;">Azolla</span></i> <i><span style="font-family:Verdana;">filiculoides</span></i><span style="font-family:Verdana;"> Lam., as determined in ongoing host range research. However, no symptomatology was</span></span><span style="font-family:""><span style="font-family:Verdana;"> observed on several economically important crop species, such as rice (</span><i><span style="font-family:Verdana;">Oryza</span></i> <i><span style="font-family:Verdana;">sativa</span></i><span style="font-family:Verdana;"> L.), corn (</span><i><span style="font-family:Verdana;">Zea</span></i> <i><span style="font-family:Verdana;">mays</span></i><span style="font-family:Verdana;"> L.), and several woody species such as bald cypress (</span><i><span style="font-family:Verdana;">Taxodium</span></i> <i><span style="font-family:Verdana;">distichum</span></i><span style="font-family:Verdana;"> L.) and loblolly pine (</span><i><span style="font-family:Verdana;">Pinus</span></i> <i><span style="font-family:Verdana;">taeda</span></i><span style="font-family:Verdana;"> L.) occurring in areas where giant salvina occurs that would be subject to contact with releases of </span></span><i><span style="font-family:Verdana;">Br</span></i><span style="font-family:""><span style="font-family:Verdana;">. These results suggest that this teleomorph of </span><i><span style="font-family:Verdana;">Botryosphaeria</span></i> <i><span style="font-family:Verdana;">rhodina</span></i><span style="font-family:Verdana;"> has potential as a bioherbicide for controlling this onerous aquatic weed. 展开更多
关键词 Biological Control Botryosphaeria rhodina (Berkeley et Curtis) Von Arx Fungal Phytopathogen Salvinia molesta D.S. Mitchell Aquatic Weed
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A Comparative Study of Different Strains of Trichoderma under Different Conditions of Temperature and pH for the Control of Rhizoctonia solani
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作者 Pérez Alejandro Andrés Pérez María Alejandra +2 位作者 Martínez Coca Benedicto Rollhaiser Ignacio Nahuel Blengini María Clara 《Agricultural Sciences》 2022年第6期702-714,共13页
Severe damage caused by R. solani in the potato crop and the current limitations for its control justify the assessment of potential biocontrol agents and their relationship with abiotic factors to be successfully inc... Severe damage caused by R. solani in the potato crop and the current limitations for its control justify the assessment of potential biocontrol agents and their relationship with abiotic factors to be successfully included in sustainable production systems. The aim of this study was to test the effect of temperature (10&#730;C, 15&#730;C, 25&#730;C, 35&#730;C) and pH (5.5, 7, 8.5) on the growth and antagonist mechanisms of 26 native strains of 11 species of Trichoderma for the control of R. solani. The response obtained was dependent on the isolation, rather than on the Trichoderma specie that was tested. Most of them showed greater growth at 25&#730;C and pH 5.5, with overgrowth values between 75% and 100% and greater percentage of radial growth inhibition (PRGI) at 50%. A greater ability to compete for the substrate is observed, enhanced by its higher growth rate. Hyphal interaction mechanisms were varied and, at least, 92% of the isolations showed a minimum of two different types. Knowledge of the behavior of the different strains in front of varied abiotic factors will enable an understanding of the population dynamic of Trichoderma and the identification of the most efficient strains for the control of R. solani. 展开更多
关键词 Biological Control Abiotic Factors PHYTOPATHOGEN
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Essential Oils from the Leaves and Flowers of Callistemon viminalis:Chemical Characterization and Evaluation of the Insecticide and Antifungal Activities
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作者 Thais Aparecida Sales Maria Das Gracas Cardoso +8 位作者 Luiz Gustavo De Lima Guimaraes Karen Caroline Camargo Danúbia Aparecida De Carvalho Selvati Rezende Rafaela Magalhães Brandao Rafaela Vieira Souza Vanúzia Rodrigues Fernandes Ferreira Ana Ermelinda Marques Maísa Lamounier Magalhaes David Lee Nelson 《American Journal of Plant Sciences》 2017年第10期2516-2529,共14页
The chemical compositions of the essential oils from the leaves and flowers of Callistemon viminalis and their insecticide and fungitoxic activities were determined. The essential oil was extracted by the hydrodistill... The chemical compositions of the essential oils from the leaves and flowers of Callistemon viminalis and their insecticide and fungitoxic activities were determined. The essential oil was extracted by the hydrodistillation method using a modified Clevenger apparatus. The chemical characterization was performed by GC-MS and GC-FID. The evaluation of the insecticidal activity was performed with the Myzus persicae aphid, and the antifungal potential was determined via the inhibition of the mycelial growth of Alternaria alternata, Fusarium oxysorum and Botrytis cinérea phytopathogenic fungi. The principal components of the essential oils from the leaves and flowers were eucalyptol (84.60% and 61.47%), α-pinene (10.28% and 21.48%) and α-terpineol (2.59% and 2.79%), respectively. The use of a 0.5% concentration of the essential oil from the flowers influenced the preference of aphids and their reproduction. The number of adult aphids decreased within a period of 48 hours in the presence of the essential oil from the leaves. In the test with no chance of choice, the mean number of adults decreased with both oils within 48 hours. No inhibition of the mycelial growth of the A. alternate microorganism was observed in any of the treatments with the two essential oils. However, the growth of F. oxysporum and B. cinerea fungi was inhibited. The mycelial growth of F. oxysporum was inhibited with the concentration of 100 μL&#183;Lˉ1 of the oil from the flowers and 250 μL&#183;Lˉ1 of the oil from the leaves. The inhibition of the growth of B. cinerea was observed at concentrations of 500 and 100 μL&#183;Lˉ1 for the oils from the flowers and leaves, respectively. The essential oils presented insecticidal and antifungal potentials. However, further studies are needed for these oils to be used in integrated pest management. 展开更多
关键词 Myzus persicae Biological Activity Phytopathogenic Fungi Natural Products
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Pull the fuzes:Processing protein precursors to generate apoplastic danger signals for triggering plant immunity
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作者 Daniele Del Corpo Daniele Coculo +2 位作者 Marco Greco Giulia De Lorenzo Vincenzo Lionetti 《Plant Communications》 SCIE CSCD 2024年第8期113-136,共24页
The apoplast is one of the first cellular compartments outside the plasma membrane encountered by phytopathogenic microbes in the early stages of plant tissue invasion.Plants have developed sophisticated surveillance ... The apoplast is one of the first cellular compartments outside the plasma membrane encountered by phytopathogenic microbes in the early stages of plant tissue invasion.Plants have developed sophisticated surveillance mechanisms to sense danger events at the cell surface and promptly activate immunity.However,a fine tuning of the activation of immune pathways is necessary to mount a robust and effective defense response.Several endogenous proteins and enzymes are synthesized as inactive precursors,and their post-translational processing has emerged as a critical mechanism for triggering alarms in the apoplast.In this review,we focus on the precursors of phytocytokines,cell wall remodeling enzymes,and proteases.The physiological events that convert inactive precursors into immunomodulatory active peptides or enzymes are described.This review also explores the functional synergies among phytocytokines,cell wall damage-associated molecular patterns,and remodeling,highlighting their roles in boosting extracellular immunity and reinforcing defenses against pests. 展开更多
关键词 APOPLAST immunity activation post-translational processing cell wall proteases pro-peptides proenzymes phytocytokines cell-wall remodeling enzymes phytopathogenic microbes plant immunity
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Assessing global fungal threats to humans 被引量:2
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作者 Jianping Xu 《mLife》 2022年第3期223-240,共18页
Fungi are an integral part of the earth's biosphere.They are broadly distributed in all continents and ecosystems and play a diversity of roles.Here,I review our current understanding of fungal threats to humans a... Fungi are an integral part of the earth's biosphere.They are broadly distributed in all continents and ecosystems and play a diversity of roles.Here,I review our current understanding of fungal threats to humans and describe the major factors that contribute to various threats.Among the 140,000 or so known species out of the estimated six million fungal species on Earth,about 10%directly or indirectly threaten human health and welfare.Major threats include mushroom poisoning,fungal allergies,infections of crop plants,food contamination by mycotoxins,and mycoses in humans.A growing number of factors have been identified to impact various fungal threats,including human demographics,crop distributions,anthropogenic activities,pathogen dispersals,global climate change,and/or the applications of antifungal drugs and agricultural fungicides.However,while models have been developed for analyzing various processes of individual threats and threat managements,current data are primarily descriptive and incomplete,and there are significant obstacles to integration of the diverse factors into accurate quantitative assessments of fungal threats.With increasing technological advances and concerted efforts to track the spatial and temporal data on climate and environmental variables;mycotoxins in the feed and food supply chains;fungal population dynamics in crop fields,human and animal populations,and the environment;human population demographics;and the prevalence and severities of fungal allergies and diseases,our ability to accurately assess fungal threats will improve.Such improvements should help us develop holistic strategies to manage fungal threats in the future. 展开更多
关键词 food contamination by mycotoxins fungal allergy fungal phytopathogens human fungal diseases mushroom poisoning
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