Selection of strains of Epicoccum purpurascens for tolerance to fungicides and improved biocontrol of Sclerotinia sclerotiorum

1990 ◽  
Vol 36 (11) ◽  
pp. 754-759 ◽  
Author(s):  
Ting Zhou ◽  
R. D. Reeleder
Keyword(s):  
Biological Control ◽  
Key Words ◽  
Sclerotinia Sclerotiorum ◽  
Fungicide Resistance ◽  
White Mold ◽  
Wild Type ◽  
Type Isolate ◽  
Type Strains ◽  
Selection Of

A wild-type isolate of Epicoccum purpurascens was exposed to shortwave ultraviolet light. One of the resulting cultures (M-20-A) was grown on media amended with the fungicides iprodione or vinclozolin and fungicide-tolerant strains were obtained. Several comparisons were made between new strains and the wild type. Sporulation was improved compared with the wild type. Strains varied in their tolerance to iprodione and vinclozolin but were not tolerant to the fungicide benomyl. Strains R4000, 16-B, and 7-A inhibited Sclerotinia sclerotiorum in vitro more than either the wild type or M-20-A, and exhibited improved control of white mold of bean in the greenhouse compared with M-20-A. Key words: biological control, fungicide resistance, white mold, iprodione, vinclozolin.

scholarly journals New isolates of Trichoderma antagonistic to Sclerotinia sclerotiorum

2016 ◽  
Vol 16 (3) ◽  
Author(s):  
Eder Marques ◽  
Irene Martins ◽  
Mariana de Oliveira Cardoso Cunha ◽  
Marcello Arrais Lima ◽  
João Batista Tavares da Silva ◽  
...  
Keyword(s):  
Biological Control ◽  
Information System ◽  
Genetic Resources ◽  
Sclerotinia Sclerotiorum ◽  
Antagonistic Activity ◽  
Biocontrol Agents ◽  
Complete Inhibition ◽  
Its Sequences ◽  
White Mold

Abstract Forty-nine isolates of Trichoderma from the Brazilian Midwest were evaluated for their antagonistic activity in vitro against Sclerotinia sclerotiorum (causal agent of white mold), which were then identified based on their nuclear ribosomal ITS sequences. Paired culture tests showed that all isolates exhibited some antagonism, with a maximum of 77% mycelial inhibition and complete inhibition of sclerotia production. Two isolates were found to be the most promising biocontrol agents, considering both antagonistic parameters (CEN1253 - T. koningiopsis and CEN1265 - T. brevicompactum). Five different species were identified: T. harzianum (23), T. spirale (9), T. koningiopsis (8), T. brevicompactum (7) and T. asperellum (2). These isolates are stored in the Embrapa Fungi Collection for Biological Control and the information obtained in the experiments will be incorporated into the database of biological assets within the genetic resources information system (Allele) and be made available for further studies.

scholarly journals Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.)

2009 ◽  
Vol 40 (1) ◽  
pp. 73-78 ◽  
Author(s):  
Rafaeli Rocha ◽  
Daniela Eleutério da Luz ◽  
Cibelle Engels ◽  
Sônia Alvim Veiga Pileggi ◽  
David de Souza Jaccoud Filho ◽  
...  
Keyword(s):  
Biological Control ◽  
Sclerotinia Sclerotiorum ◽  
Endophytic Fungi ◽  
Symphytum Officinale ◽  
Selection Of

An endophytic chitinase-producing isolate of Actinoplanes missouriensis, with potential for biological control of root rot of lupin caused by Plectosporium tabacinum

2003 ◽  
Vol 51 (3) ◽  
pp. 257 ◽  
Author(s):  
Khaled A. El-Tarabily
Keyword(s):  
Biological Control ◽  
Cell Wall ◽  
Root Rot ◽  
Germ Tube ◽  
First Record ◽  
Plant Roots ◽  
Wild Type ◽  
Type Isolate ◽  
Cell Wall Lysis

Twenty-one streptomycete and 15 non-streptomycete actinomycetes were isolated from surface-disinfested lupin roots and evaluated for their potential to produce chitinase and to inhibit the growth of Plectosporium tabacinum, the causal agent of lupin root rot in Egypt. The most inhibitory isolate was identified as Actinoplanes missouriensis which produced relatively high levels of chitinase and degraded the hyphae of P.�tabacinum in vitro, causing extensive plasmolysis and cell-wall lysis. A crude culture filtrate of A. missouriensis exhibited antifungal activity and significantly (P < 0.05) reduced spore germination and germ-tube growth of the pathogen. The antagonist was recovered from inside the root at all samplings up to 8 weeks after inoculation, indicating that the roots of healthy lupin may be a habitat for the endophyte. A. missouriensis significantly (P < 0.05) reduced the severity of root rot under glasshouse conditions. An endophytic isolate of Actinoplanes italicus incapable of producing chitinase and a mutant strain of A. missouriensis that did not produce detectable levels of chitinase, did not lyse hyphae of P. tabacinum or reduce root rot in the glasshouse experiments, although colonisation of the lupin root by both these isolates was similar to that of the chitinase-producing wild-type isolate of A. missouriensis. This study is the first record of control of a soil-borne plant pathogen by a chitinolytic actinomycete, endophytic in plant roots.

scholarly journals Pharmacodynamics of Itraconazole against Aspergillus fumigatus in anIn VitroModel of the Human Alveolus: Perspectives on the Treatment of Triazole-Resistant Infection and Utility of Airway Administration

2012 ◽  
Vol 56 (8) ◽  
pp. 4146-4153 ◽  
Author(s):  
Zaid Al-Nakeeb ◽  
Ajay Sudan ◽  
Adam R. Jeans ◽  
Lea Gregson ◽  
Joanne Goodwin ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Therapeutic Strategies ◽  
Wild Type ◽  
Content Type ◽  
Exposure Response ◽  
Prevention And Treatment ◽  
Resistant Infection ◽  
Resistant Strains ◽  
Type Strains

ABSTRACTItraconazole is used for the prevention and treatment of infections caused byAspergillus fumigatus. An understanding of the pharmacodynamics of itraconazole against wild-type and triazole-resistant strains provides a basis for innovative therapeutic strategies for treatment of infections. Anin vitromodel of the human alveolus was used to define the pharmacodynamics of itraconazole. Galactomannan was used as a biomarker. The effect of systemic and airway administration of itraconazole was assessed, as was a combination of itraconazole administered to the airway and systemically administered 5FC. Systemically administered itraconazole against the wild type induced a concentration-dependent decline in galactomannan in the alveolar and endothelial compartments. No exposure-response relationships were apparent for the L98H, M220T, or G138C mutant. The administration of itraconazole to the airway resulted in comparable exposure-response relationships to those observed with systemic therapy. This was achieved without detectable concentrations of drug within the endothelial compartment. The airway administration of itraconazole resulted in a definite but submaximal effect in the endothelial compartment against the L98H mutant. The administration of 5FC resulted in a concentration-dependent decline in galactomannan in both the alveolar and endothelial compartments. The combination of airway administration of itraconazole and systemically administered 5FC was additive. Systemic administration of itraconazole is ineffective against Cyp51 mutants. The airway administration of itraconazole is effective for the treatment of wild-type strains and appears to have some activity against the L98H mutants. Combination with other agents, such as 5FC, may enable the attainment of near-maximal antifungal activity.

scholarly journals Selection of Trichoderma spp. strains for the control of Sclerotinia sclerotiorum in soybean

2017 ◽  
Vol 52 (12) ◽  
pp. 1140-1148 ◽  
Author(s):  
Patrícia Elias Haddad ◽  
Luis Garrigós Leite ◽  
Cleusa Maria Mantovanello Lucon ◽  
Ricardo Harakava
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Culture Medium ◽  
Harmful Effect ◽  
Soybean Seeds ◽  
Trichoderma Spp ◽  
Negative Effect ◽  
Soybean Plants ◽  
Selection Of

Abstract: The objective of this work was to evaluate, in vitro and in vivo, the potential of Trichoderma spp. strains to control Sclerotinia sclerotiorum in soybeans (Glycine max) and to perform the molecular identification of the best perfoming strains. The effect of 120 strains of Trichoderma spp. on the viability of S. sclerotiorum sclerotia was evaluated in vitro through immersion in suspension of conidia from the antagonists and plating in culture medium. The best performing strains were evaluated in vivo, in a greenhouse, for control of the pathogen inoculated on 'Pintado' soybean seeds and plants. Of the 120 strains tested in vitro, 22 strains of Trichoderma spp. caused 100% inhibition of sclerotia germination. In the greenhouse, five strains inhibited the negative effect of the pathogen on seed germination and two strains increased in up to 67% plant dry matter. The best performing strains were identified as T. koningiopsis (3 strains), T. asperelloides (3), T. atroviride (2), and T. virens (1). Trichoderma strains are able to protect soybean plants from the harmful effect of S. sclerotiorum and, at the same time, they can promote the growth of the aerial part in greenhouse conditions.

scholarly journals Evaluation of Accessory Gene Regulator (agr) Group and Function in the Proclivity towards Vancomycin Intermediate Resistance in Staphylococcus aureus

2006 ◽  
Vol 51 (3) ◽  
pp. 1089-1091 ◽  
Author(s):  
Brian T. Tsuji ◽  
Michael J. Rybak ◽  
Kerry L. Lau ◽  
George Sakoulas
Keyword(s):  
Staphylococcus Aureus ◽  
Wild Type ◽  
Accessory Gene ◽  
Time Curve ◽  
Unbound Fraction ◽  
Accessory Gene Regulator ◽  
Intermediate Resistance ◽  
And Function ◽  
Type Strains

ABSTRACT Simulated therapeutic vancomycin exposures were evaluated against agr wild-type and knockout Staphylococcus aureus groups I, II, III, and IV using an in vitro pharmacodynamic model. All agr groups developed intermediate resistance to vancomycin after subtherapeutic exposure. The free unbound fraction of the area under the concentration-time curve (fAUC/MIC) required to suppress resistance was fourfold higher (P < 0.001) in agr dysfunctional strains (112 to 169) than that in parent wild-type strains (28).

scholarly journals Prion replication without host adaptation during interspecies transmissions

2017 ◽  
Vol 114 (5) ◽  
pp. 1141-1146 ◽  
Author(s):  
Jifeng Bian ◽  
Vadim Khaychuk ◽  
Rachel C. Angers ◽  
Natalia Fernández-Borges ◽  
Enric Vidal ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Protein Misfolding ◽  
Guanidine Hydrochloride ◽  
Host Adaptation ◽  
Wild Type ◽  
Epidemiological Features ◽  
Significant Barrier ◽  
Prion Transmission ◽  
Selection Of

Adaptation of prions to new species is thought to reflect the capacity of the host-encoded cellular form of the prion protein (PrPC) to selectively propagate optimized prion conformations from larger ensembles generated in the species of origin. Here we describe an alternate replicative process, termed nonadaptive prion amplification (NAPA), in which dominant conformers bypass this requirement during particular interspecies transmissions. To model susceptibility of horses to prions, we produced transgenic (Tg) mice expressing cognate PrPC. Although disease transmission to only a subset of infected TgEq indicated a significant barrier to EqPrPCconversion, the resulting horse prions unexpectedly failed to cause disease upon further passage to TgEq. TgD expressing deer PrPCwas similarly refractory to deer prions from diseased TgD infected with mink prions. In both cases, the resulting prions transmitted to mice expressing PrPCfrom the species of prion origin, demonstrating that transmission barrier eradication of the originating prions was ephemeral and adaptation superficial in TgEq and TgD. Horse prions produced in vitro by protein misfolding cyclic amplification of mouse prions using horse PrPCalso failed to infect TgEq but retained tropism for wild-type mice. Concordant patterns of neuropathology and prion deposition in susceptible mice infected with NAPA prions and the corresponding prion of origin confirmed preservation of strain properties. The comparable responses of both prion types to guanidine hydrochloride denaturation indicated this occurs because NAPA precludes selection of novel prion conformations. Our findings provide insights into mechanisms regulating interspecies prion transmission and a framework to reconcile puzzling epidemiological features of certain prion disorders.

scholarly journals Seleksi Primer LCO – HCO, Primer bird-f1 – HCO Dan Primer bch – bcl Untuk Amplifikasi Gen COI DNA Mitokondria Itik Magelang (Anas javanica)

2014 ◽  
Vol 16 (2) ◽  
pp. 83
Author(s):  
Sonny Abdi Setiyawan ◽  
Anto Budiharjo ◽  
Hermin Pancasakti Kusumaningrum
Keyword(s):  
Mitochondrial Dna ◽  
Key Words ◽  
Coi Gene ◽  
Wild Type ◽  
High Production ◽  
Partial Homology ◽  
Selection Of

Magelang duck is a wild type of local duck from Indonesia. The advantagesof Magelangduckcompare tootherlocalduck from Indonesiaareabilityto livein the highlandsandlowlands and high production of egg and meat. Geneticcharacterization of Magelangduck still not available until now.The aim of the research is selectprimers forampliflying COIgeneof mitochondrialDNAof MagelangduckusingLCO-HCO, bird-f1 -HCO, andbcl-bch primers.The research methodwas DNAisolationfrom Magelangduck. Followed by, selection of primer in silicoto find homologywithin COIsequenceusing ClustalX, Genedoc, and FastPCR programs. Amplification of COIgenewas performedusing PCRwith all primerpairs. Result showed partial homology with all primer in COI sequence. TheamplificationusingtheLCO-HCO primer produced  primerdimer.Primerbirdf1-HCOand bch-bcl primers showed no amplification.   Key words: Magelang duck, COI gene, mitochondrial DNA, primer

scholarly journals Mutants of Listeria monocytogenes Defective in In Vitro Invasion and Cell-to-Cell Spreading Still Invade and Proliferate in Hepatocytes of Neutropenic Mice

2000 ◽  
Vol 68 (2) ◽  
pp. 912-914 ◽  
Author(s):  
Rui Appelberg ◽  
Irene S. Leal
Keyword(s):  
Monoclonal Antibody ◽  
Listeria Monocytogenes ◽  
Cell Spreading ◽  
Histologic Examination ◽  
Gene Products ◽  
Wild Type ◽  
In Vitro Invasion ◽  
Parenchymal Cells ◽  
Type Strains

ABSTRACT Listeria monocytogenes mutants defective in theactA gene, the plcB gene, and theinlA and inlB genes were less virulent when injected intravenously into BALB/c mice. The growth of these strains as well as of the virulent wild-type strains was increased by treating mice with a neutrophil-specific depleting monoclonal antibody, RB6-8C5. Histologic examination of the livers of the treated animals showed intrahepatocytic proliferation of the listeriae in all cases. Our data show that more than one pathway exists that allows L. monocytogenes to invade parenchymal cells. One pathway most likely involves the actA and plcB gene products, and a second one probably involves the internalins.

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