Influence de la monensine sur la croissance et la sécrétion des exopolysaccharides chez le Botrytis cinerea Pers. et le Sclerotium rolfsii Sacc.

1996 ◽  
Vol 42 (9) ◽  
pp. 965-972 ◽  
Author(s):  
Yahya Koulali ◽  
Ahmed Talouizte ◽  
Jean-Louis Fonvieille ◽  
Robert Dargent
Keyword(s):  
Botrytis Cinerea ◽  
Culture Medium ◽  
Sclerotium Rolfsii ◽  
Fungal Growth ◽  
Polymer Composition ◽  
Composition And Structure ◽  
Normal Wall

The addition of various concentrations of monensin (1, 5, and 10 μg/mL) to the culture medium inhibits the fungal growth and perturbs exopolysaccharides secretion, provoking a decrease of production in Botrytis cinerea and an increase in Sclerotium rolfsii. The ionophore induces also modifications in both polymer composition and structure. New monomers were observed in the two species and a decreased branching rate for Sclerotium rolfsii. These modifications show that monensin affects the enzymes responsible for normal wall synthesis and therefore vesicular traffic.Key words: monensin, growth, exopolysaccharides, Botrytis cinerea, Sclerotium rolfsii.

scholarly journals A Basidiomycete Fungus Responsible for Fresh Mushroom Off-Flavour in Wines: Crustomyces subabruptus, (Bourdot & Galzin) Jülich 1978

OENO One ◽  
2021 ◽  
Vol 55 (3) ◽  
pp. 283-298
Author(s):  
Eric Meistermann ◽  
Stéphanie Villaumé ◽  
Delphine Goffette ◽  
Corinne Trarieux ◽  
Morvan Coarer ◽  
...  
Keyword(s):  
Botrytis Cinerea ◽  
Culture Medium ◽  
Fungal Growth ◽  
Grape Juice ◽  
Warm Environment ◽  
Its Regions ◽  
The Subject ◽  
Basidiomycete Fungus

Grape rot can cause organoleptic deviations in wines, including the aroma of fresh mushrooms; one of the molecules responsible for this is 1-octen-3-one. The bunches affected by this defect are often contaminated by Botrytis cinerea; however, they may also contain a whitish mycelium that cannot be attributed to B. cinerea. This additional fungal growth is the subject of this study.  Several isolations of this fungus were carried out on grape bunches from different vineyards in the French Alsace and Champagne regions using a culture medium containing an anti-Botrytis fungicide (Boscalid). The sequencing of the ITS regions showed that most isolations corresponded to Crustomyces subabruptus (Bourdot & Galzin; Jülich 1978), an endophyte basidiomycete. Contamination tests carried out on bunches and grape juice with this fungus confirmed its responsibility for the appearance of fresh mushroom defects in wines, and showed that it has the capacity to produce large quantities of 1-octen-3-one in a wet and warm environment. The results of this study suggest that this basidiomycete is responsible for fresh mushroom aromas in wines.

The regulation of sclerotium initiation in Sclerotium rolfsii by glucose and cyclic AMP

1983 ◽  
Vol 29 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Y. Hadar ◽  
M. Pines ◽  
I. Chet ◽  
Y. Henis
Keyword(s):  
Culture Medium ◽  
Sclerotium Rolfsii ◽  
Fungal Growth ◽  
Maximal Level ◽  
Glucose Addition ◽  
Glucose Depletion ◽  
Endogenous Substrates ◽  
Further Development ◽  
Wall Components ◽  
Glucose Supplementation

Sclerotium rolfsii, grown in a shaken submerged culture, developed a potential for the formation of sclerotia. This potential was inhibited by the presence of glucose in the culture medium. The cultures were capable of producing sclerotia, after transfer to stationary incubation, when glucose was exhausted and the biomass reached its maximal level. The level of adenosine 3′,5′-cyclic monophosphate (cAMP) sharply increased upon glucose depletion and decreased upon glucose addition. Sclerotium rolfsii was grown in a chemostat with glucose of limiting concentration at a dilution rate of 0.05/h. Samples from the chemostat possessed the potential to produce initials when poured into empty Petri plates. Addition of glucose to these plates changed the fungal growth pattern from further differentiation to vegetative growth. Glucose supplementation to clearly differentiated initials did not inhibit further development. It was observed that during morphogenetic events endogenous substrates, e.g., cell wall components, were utilized.

Influence de la monensine sur la composition lipidique et protéique des culots membranaires chez Botrytis cinerea Pers. et Sclerotium rolfsii Sacc.

1998 ◽  
Vol 44 (10) ◽  
pp. 937-944 ◽  
Author(s):  
Yahya Koulali ◽  
Jean Louis Fonvieille ◽  
Abbes Es-Sgaouri ◽  
Robert Dargent
Keyword(s):  
Botrytis Cinerea ◽  
Sclerotium Rolfsii ◽  
Vesicular Traffic ◽  
Chemical Content

Membranes of young hyphae of Botrytis cinerea and Sclerotium rolfsii in the presence or absence of monensin were isolated and their chemical content was determined. Monensin induced a reduction of protein/lipid and sterol/phospholipid ratios. These modifications show that monensin affects vesicular traffic and also both the normal biosynthesis and growth.Key words: monensin, membranes, Botrytis cinerea, Sclerotium rolfsii.

Chemical control of fungal growth and ochratoxin A production by Aspergillus isolated from Moroccan grapes

2018 ◽  
Vol 7 (2) ◽  
pp. 84-91
Author(s):  
Adil Laaziz ◽  
Souad Qjidaa ◽  
Yousra El Hammoudi ◽  
Abdelouahed Hajjaji ◽  
Amina Bouseta
Keyword(s):  
Ochratoxin A ◽  
Radial Growth ◽  
Culture Medium ◽  
Fungal Growth ◽  
Sublethal Concentration ◽  
Agar Culture ◽  
Total Inhibition ◽  
Yeast Autolysate ◽  
Germination And Growth ◽  
Czapek Yeast Autolysate Agar

The aim of this study was to evaluate the effect of three fungicides azoxystrobin (Ortiva), hexaconazole (Hexa) and pyrimethanil (Pyrus) for their ability to inhibit the radial growth and ochratoxin A (OTA) production by five ochratoxigenic strains of Aspergillus carbonarius and A. niger previously iso-lated from Moroccan grapes. Our results showed that, the addition of the fungicides to the Czapek Yeast Autolysate agar culture medium reduced the growth of the ochratoxigenic strains. Pyrimethanil caused total inhibition of spore germination and growth of the five strains, for all dose tested. Where-as hexaconazole totally inhibited the growth of 4 strains and gave growth for the MUCL 49227 strain (2.67 mm/day) at sublethal concentration. The reduction in radial growth was less marked for azoxystrobin, with growth rate varying between 0 and 6.37 mm/day depending on the strain and the azoxystrobin concentration. Analysis of variance showed that the effect of single factors (fungicides, concentration and strain) and their interactions on growth and OTA production were highly significant (P=0.000).These findings suggest that the use of tested fungicides have to potential for reduction in production of OTA.

scholarly journals Selection of filamentous fungi that are resistant to the herbicides atrazine, glyphosate and pendimethalin

2021 ◽  
Vol 43 ◽  
pp. e51656
Author(s):  
Nara Priscila Barbosa Bravim ◽  
Anatércia Ferreira Alves ◽  
José Fábio França Orlanda ◽  
Patricia Barbosa Rodrigues Silva
Keyword(s):  
Filamentous Fungi ◽  
Mycelial Growth ◽  
Culture Medium ◽  
Agricultural Soils ◽  
Culture Media ◽  
Fusarium Verticillioides ◽  
Fungal Growth ◽  
Relative Growth ◽  
Maximum Inhibition ◽  
Selection Of

The objective of the present study was to isolate fungi from agricultural soils and evaluate fungal growth in culture medium contaminated with atrazine, glyphosate and pendimethalin. Filamentous fungi were isolated from agricultural soils and cultured in a modified culture medium containing 0, 10, 20, 50, and 100 μg mL-1 atrazine, glyphosate and pendimethalin for 14 days at 28°C. The fungi that presented optimal and satisfactory growth were plated in Sabouraud culture medium with 4% dextrose and containing the herbicides at concentrations of 0, 10, 20, 50, and 100 μg mL-1 for seven days at 28°C. The mean mycelial growth values were submitted to analysis of variance and the Tukey test (p < 0.05%) for comparison and relative growth determination, and maximum inhibition rates were calculated. The isolated fungi Aspergillus fumigatus, Fusarium verticillioides and Penicillium citrinum were shown to be resistant to atrazine, glyphosate and pendimethalin. F. verticillioides showed higher mean mycelial growth in the culture media contaminated with atrazine and glyphosate than the other two fungi. In the culture medium contaminated with pendimethalin, F. verticillioides, and A. fumigatus presented the highest mean mycelial growth values.

scholarly journals Effective medium for in vitro sprouting of the buds and multiplication of the plantlets, and identification of the fungal contaminant associated with the explants of Gnetum

2021 ◽  
Vol 16 (2) ◽  
pp. 001-013
Author(s):  
Abwe Mercy Ngone ◽  
Lawrence Monah Ndam ◽  
Rita Mungfu Njilar ◽  
Doungous Oumar ◽  
Thomas Eku Njock
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Fungal Growth ◽  
Growth Media ◽  
Fungal Contamination ◽  
Surface Sterilization ◽  
Pure Cultures ◽  
Nodal Cuttings ◽  
Baseline Information

Plant tissue culture requires the optimization of growth media. Gnetum, known locally in Cameroon as “Eru” is an indigenous gymnospermous vegetable with diverse medicinal, nutritional, cultural and socio-economic values. This resource is over-exploited and expected to neighboring countries, resulting to increased scarcity in the forest. Preliminary work on the in vitro culture of nodal cuttings was faced by the problem of fungal contamination. It was therefore necessary to isolate and identify the fungal contaminant, optimize the surface sterilization of field material and compose an appropriate medium for sprouting. Pure cultures of the fungus were obtained and grown on Potato Dextrose Agar (PDA) and Sabouraud Dextrose Agar (SDA). The identification was based on the appearance of the fungal growth on plates and also on the microscopic view. This was affected by the use of keys. Gnetum explants were disinfected with the various concentrations of disinfectants, preceded in some instances by pre-treatments, as well as incorporating fungicides in the culture medium. Two different culture media were employed: the Woody Plant Medium (WPM) and the Murashige and Skoog (MS) based establishment medium (Y-1). Gnetum was found to live in association with a complex of Microsporum species. The level of contamination of cultures was reduced from 100% to 40% when pre-treated before disinfection and even lower to 10% by incorporating fungicides in the medium. Sprouting was observed in WPM. This study provides baseline information on the in vitro propagation of Gnetum and thus opens up avenues for more research to be carried out in this field.

scholarly journals In vitro establishment of Bambusa oldhamii Munro from field-grown matrices and molecular identification of endophytic bactéria

2019 ◽  
Vol 49 ◽  
Author(s):  
Ana Paula de Azevedo Pasqualini ◽  
Gabriela Xavier Schneider ◽  
Hugo Pacheco de Freitas Fraga ◽  
Luiz Antonio Biasi ◽  
Marguerite Quoirin
Keyword(s):  
Molecular Identification ◽  
Culture Medium ◽  
Bacterial Isolate ◽  
Fungal Growth ◽  
Endophytic Bacterium ◽  
Liquid Culture Medium ◽  
Rdna Sequencing ◽  
In Vitro Establishment ◽  
Bambusa Oldhamii

ABSTRACT In plant micropropagation, the establishment stage is difficult, due to the presence of microorganisms in tissues from field-grown matrices, especially for bamboo. This study aimed to establish an efficient asepsis protocol for Bambusa oldhamii explants from field plants, as well as to carry out the molecular identification of a possible endophytic bacterial isolate. The explants were exposed to 70 % alcohol, 1 % sodium hypochlorite (NaOCl), 0.1 % mercuric chloride (HgCl2), thiophanate-methyl (Cercobin®) and chlorhexidine digluconate (2 % Riohex®) in different combinations, and introduced into Murashige and Skoog culture medium (solid or liquid), supplemented or not with 4 mL L-1 of Plant Preservative Mixture (PPMTM), totaling seven treatments. The asepsis and immersion of the explants in the liquid culture medium containing 4 mL L-1 of PPMTM visually inhibited the bacterial and fungal growth, allowed the development of shoots with a mean length of 2.2 cm and posterior subcultures, being the best treatment used for the in vitro establishment of B. oldhamii. The molecular identification of an endophytic bacterium performed by 16S rDNA sequencing allowed to identify the bacterial isolate as Ralstonia sp., with 100 % of similarity, and the phylogenetic analysis grouped it with Ralstonia pickettii. In addition, the bacterial isolate showed to be sensitive to 4 mL L-1 of PPMTM by the minimum inhibitory concentration test.

scholarly journals Effects of Fruit and Pollen Exudates on Growth of Botrytis cinerea and Infection of Plum and Nectarine Fruit

Plant Disease ◽  
1998 ◽  
Vol 82 (2) ◽  
pp. 165-170 ◽  
Author(s):  
J. F. Fourie ◽  
G. Holz
Keyword(s):  
Botrytis Cinerea ◽  
Culture Media ◽  
Fungal Growth ◽  
Steady Increase ◽  
Gas Liquid Chromatography ◽  
Immature Fruit ◽  
Sugar Release ◽  
Hexose Sugars

Sugars in exudates from Harry Pickstone plum and Sunlite nectarine fruit and from pollen of weeds commonly found in orchards were determined by gas-liquid chromatography, and their effect on the development of Botrytis cinerea was determined in vitro and in vivo. Fructose, glucose, and sorbitol were the only sugars detected in exudates of immature fruit. They occurred at low concentrations, but their concentration generally increased as fruit ripened. Sucrose was first detected during maturation. In nectarine, an increase in sugar concentration, especially sucrose, was pronounced during the period of rapid cell enlargement, which occurred approximately 2 weeks before harvest. Absorbance readings of culture media amended with sugar indicated that the hexose sugars (fructose and glucose) and sucrose did not markedly influence growth of B. cinerea at concentrations below 0.22 and 0.12 mM, respectively. The hexose sugars caused a steady increase in growth when supplied at concentrations in excess of 0.44 mM, and sucrose caused a steady increase in growth at 0.23 mM. The stimulatory effect of fruit exudates on growth of B. cinerea on glass slides coincided with the period of rapid sugar release from the fruit and the shift in susceptibility to decay. Only fructose (1.72 mM) and glucose (0.72 mM) were detected in nectarine pollen exudates. Pollen exudates from weeds stimulated fungal growth and significantly increased the aggressiveness of the pathogen on plum and nectarine fruit when added to conidia during the last 4 weeks prior to the picking-ripe stage. The study showed that changes in the composition of nectarine and plum fruit exudates may contribute to the late-season susceptibility of these fruit to B. cinerea infection.

Influence de la monensine sur la composition des parois de quelques champignons filamenteux

1992 ◽  
Vol 38 (4) ◽  
pp. 277-283 ◽  
Author(s):  
Yahya Koulali ◽  
Jean-Louis Fonvieille ◽  
Jane-Marie Touze-Soulet ◽  
Émile Benizri ◽  
Robert Dargent
Keyword(s):  
Chemical Composition ◽  
Key Words ◽  
Botrytis Cinerea ◽  
Uronic Acid ◽  
Sclerotium Rolfsii ◽  
Total Lipids ◽  
Chemical Content ◽  
Neutral Sugars ◽  
Achlya Bisexualis

Walls of young hyphae of Achlya bisexualis, Botrytis cinerea, and Sclerotium rolfsii growing in the presence or the absence of monensin were isolated and their chemical content was determined. Monensin induced modified proportions of various monomers resulting in a reduction of the (neutral sugars + uronic acid)/amine sugar ratio of B. cinerea and S. rolfsii (species of group chitin–glucans), and of cellulose in A. bisexualis (species of group cellulose-glucans).The walls of hyphae grown in presence of monensin also contained less total lipids and proteins. These modificationsin chemical composition are related to changes in cytological structure. Key words: fungi, monensin, wall.

An aspartic proteinase gene family in the filamentous fungus Botrytis cinerea contains members with novel features

Microbiology ◽  
2004 ◽  
Vol 150 (7) ◽  
pp. 2475-2489 ◽  
Author(s):  
Arjen ten Have ◽  
Ester Dekkers ◽  
John Kay ◽  
Lowri H. Phylip ◽  
Jan A. L. van Kan
Keyword(s):  
Botrytis Cinerea ◽  
Culture Medium ◽  
Infected Plant ◽  
Aspartic Proteinase ◽  
Proteinase Activity ◽  
In Planta ◽  
Wheat Germ Extract ◽  
Fungal Plant Pathogen ◽  
Genes Encoding ◽  
Metalloproteinase Activity

Botrytis cinerea, an important fungal plant pathogen, secretes aspartic proteinase (AP) activity in axenic cultures. No cysteine, serine or metalloproteinase activity could be detected. Proteinase activity was higher in culture medium containing BSA or wheat germ extract, as compared to minimal medium. A proportion of the enzyme activity remained in the extracellular glucan sheath. AP was also the only type of proteinase activity in fluid obtained from B. cinerea-infected tissue of apple, pepper, tomato and zucchini. Five B. cinerea genes encoding an AP were cloned and denoted Bcap1–5. Features of the encoded proteins are discussed. BcAP1, especially, has novel characteristics. A phylogenetic analysis was performed comprising sequences originating from different kingdoms. BcAP1 and BcAP5 did not cluster in a bootstrap-supported clade. BcAP2 clusters with vacuolar APs. BcAP3 and BcAP4 cluster with secreted APs in a clade that also contains glycosylphosphatidylinositol-anchored proteinases from Saccharomyces cerevisiae and Candida albicans. All five Bcap genes are expressed in liquid cultures. Transcript levels of Bcap1, Bcap2, Bcap3 and Bcap4 are subject to glucose and peptone repression. Transcripts from all five Bcap genes were detected in infected plant tissue, indicating that at least part of the AP activity in planta originates from the pathogen.

Sign in / Sign up

Export Citation Format

Share Document