SURVEYS FOR FUNGAL PATHOGENS OF LOCUSTS AND GRASSHOPPERS IN AFRICA AND THE NEAR EAST

1997 ◽  
Vol 129 (S171) ◽  
pp. 27-35 ◽  
Author(s):  
P.A. Shah ◽  
C. Kooyman ◽  
A. Paraïso
Keyword(s):  
Metarhizium Anisopliae ◽  
Fungal Pathogens ◽  
Research Programme ◽  
Screening Tests ◽  
Culture Collections ◽  
Soil Baiting ◽  
Microbial Insecticide ◽  
Selective Agar ◽  
Agar Media ◽  
Highly Virulent

AbstractA total of 181 isolates of Metarhizium anisopliae (Metschnikoff) Sorokin, M. flavoviride Gams and Rozsypal, Beauveria bassiana (Balsamo) Vuillemin, and Sorosporella sp. was found in a survey of Orthoptera in West Africa, Madagascar, Oman, and Pakistan between 1990 and 1993. Prior to this survey, there were only 28 isolates of hyphomycete fungi from Orthoptera held in international culture collections. Seventeen of the recently acquired Metarhizium isolates have been determined to be highly virulent during screening tests as part of a research programme for the development of a microbial insecticide against locusts and grasshoppers in Africa. Ninety-five isolates came from Benin which was the country where survey activities were most concentrated, and 63 of these isolates were found in Malanville, northern Benin, between 1991 and 1992 during an epizootic of M. flavoviride. Recordings from Oman and Pakistan represent the first specimens from these countries to be deposited in international culture collections. No deductions can be made on the best method for survey; both incubation of live grasshoppers and field searches for cadavers yielded results. Soil baiting with Orthoptera was used with some success. Limited soil screening using selective agar media was not found to be particularly useful.

Assessment of different selective agar media for enumeration and isolation ofListeriafrom dairy products

1988 ◽  
Vol 55 (4) ◽  
pp. 579-583 ◽  
Author(s):  
Lucas Dominguez ◽  
José Francisco Fernández ◽  
Victor Briones ◽  
José Luis Blanco ◽  
Guillermo Suárez
Keyword(s):  
Dairy Products ◽  
Agar Medium ◽  
Raw Milk ◽  
Superior Performance ◽  
Direct Plating ◽  
Selective Agar ◽  
Natural Microflora ◽  
Agar Media ◽  
The Difference ◽  
Better Than

SummaryDifferent selective agar media were compared for the recovery and isolation of five species ofListeriafrom raw milk and cheese. The selective media examined were Beerens medium, MacBride medium and that described by Dominguezet al.(1984) with 6 mg/1 acriflavine, listeria selective agar medium (LSAM), and LSAM with 12 mg/1 acriflavine (LSAM × 2A); a non-selective yeast glucose Lemco agar was included for comparison. When the difference between listeria and the natural microflora of raw milk and cheese was 102cfu/ml, listeria could be isolated by direct plating on all media tested. When it was lower than 103–104cfu/ml, listeria were isolated by direct plating only on LSAM and LSAM × 2A. When the difference was greater than 104cfu/ml, a previous enrichment was necessary to isolate them. LSAM and LSAM × 2A media performed better than the other media tested for isolating listeria by direct plating and improved their isolation from dairy products. This superior performance was evaluated by the ability of these media to support colony formation of different species ofListeriatested, the easy recognition of these colonies from those formed by other microorganisms and by their capacity to inhibit the natural microflora of these foods.

scholarly journals First Description of Two Sequence Type 2 Acinetobacter baumannii Isolates Carrying OXA-23 Carbapenemase in Pagellus acarne Fished from the Mediterranean Sea near Bejaia, Algeria

2016 ◽  
Vol 60 (4) ◽  
pp. 2513-2515 ◽  
Author(s):  
Soumia Brahmi ◽  
Abdelaziz Touati ◽  
Axelle Cadière ◽  
Nassima Djahmi ◽  
Alix Pantel ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Mediterranean Sea ◽  
Sequence Type ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Selective Agar ◽  
Agar Media ◽  
The Mediterranean ◽  
First Time

ABSTRACTTo determine the occurrence of carbapenem-resistantAcinetobacter baumanniiin fish fished from the Mediterranean Sea near the Bejaia coast (Algeria), we studied 300 gills and gut samples that had been randomly and prospectively collected during 1 year. After screening on selective agar media, using PCR arrays and whole-genome sequencing, we identified for the first time two OXA-23-producingA. baumanniistrains belonging to the widespread sequence type 2 (ST2)/international clone II and harboring aminoglycoside-modifying enzymes [aac(6′)-Ib andaac(3′)-I genes].

Procedures for Recovery of Stressed and Injured Cells of Yersinia Enterocolitica from Meat and Meat Products

1989 ◽  
Vol 52 (5) ◽  
pp. 360-362 ◽  
Author(s):  
ZHEKO KOUNEV
Keyword(s):  
Yersinia Enterocolitica ◽  
Agar Medium ◽  
Alkali Treatment ◽  
Meat Products ◽  
The Other ◽  
Step Procedure ◽  
Selective Agar ◽  
Agar Media ◽  
Phosphate Buffered Saline

A new three-step procedure (TSP) for the recovery of Yersinia enterocolitica 0:3 from frozen meat, salted and dried meat products, raw dried meat products, and cooked perishable sausages, has been developed. The TSP is based mainly on enrichment in 0.15 M phosphate-buffered saline at 25°C. In the TSP, selected dilutions of samples are enriched for 1, 2, 3, 4, 24, and 48 h and then plated onto nonselective and selective agar media after or without alkali treatment. Additional enrichment was performed with half of the samples at 25°C for 24 h, and the rest at 4°C for up to 2 wk, followed by alkali treatment and plating on selective agar medium. Recovery of Y. enterocolitica was better using the TSP than the other method used for isolating the organism from meats.

Method of Applying Sanitizers and Sample Preparation Affects Recovery of Native Microflora and Salmonella on Whole Cantaloupe Surfaces†

2004 ◽  
Vol 67 (5) ◽  
pp. 999-1004 ◽  
Author(s):  
DIKE O. UKUKU ◽  
WILLIAM F. FETT
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Treatment Method ◽  
Microbial Populations ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Selective Media ◽  
Selective Agar ◽  
Agar Media ◽  
Native Microflora

Standardized methods for applying sanitizer treatments to cantaloupes and for recovering surviving native microflora or Salmonella on inoculated cantaloupe after sanitizing are lacking. Accordingly, the objectives of this study were to compare four methods for applying sanitizers (dipping, dipping with rotation, dipping with agitation, and dipping with rubbing) using 200 ppm of chlorine or 5% H2O2, two recovery methods (homogenization of rind plugs in a stomacher or blender), and five selective recovery media for Salmonella. Whole cantaloupes were submerged in a cocktail of five strains of Salmonella (each at approximately 2 × 108 CFU/ml) for 10 min and allowed to dry for 1 h inside a biosafety cabinet and stored at 20° C for approximately 23 h before sanitizing. The recovery of Salmonella from whole cantaloupe without sanitizing averaged 5.09 log CFU/cm2 by blending and 4.30 log CFU/cm2 by homogenization in a stomacher for the five selective agar media. Microbial populations ( Salmonella or the indigenous aerobic mesophilic bacteria, gram-negative bacteria, lactic acid bacteria, Pseudomonas spp., and yeast and mold) were not significantly (P > 0.05) reduced by treating with water regardless of the treatment method used. Sanitizing with chlorine or H2O2 by dipping, with or without rotation for 2 min, also did not reduce microbial populations. However, populations of all classes of native microflora and Salmonella were significantly (P < 0.05) reduced by sanitizer treatments (2 min) applied with agitation or by rubbing. In general, sanitizer treatments applied by rubbing resulted in greater log reductions (by up to 1.7 log unit) than for treatments applied with agitation. Populations of native microflora and Salmonella recovered from cantaloupe were higher (by up to 1.8 log unit) by blending compared to homogenization in a stomacher. In most instances, selective media used did not differ significantly (P > 0.05) for recovery of Salmonella after washing treatments.

Baseline Sensitivities of Major Citrus, Pome, and Stone Fruits Postharvest Pathogens to Natamycin and Estimation of the Resistance Potential in Penicillium digitatum

Plant Disease ◽  
2020 ◽  
Author(s):  
Daniel Chen ◽  
Helga Forster ◽  
James Adaskaveg
Keyword(s):  
Mycelial Growth ◽  
Fungal Pathogens ◽  
Wide Spectrum ◽  
The United States ◽  
Management Program ◽  
Penicillium Digitatum ◽  
Stone Fruits ◽  
Concentration Gradients ◽  
Food Preservative ◽  
Agar Media

Natamycin is a biofungicide that was recently registered for postharvest use on citrus and stone fruits in the United States. It has been used as a food preservative for many decades, with no resistance ever observed to date. The objective of this study was to determine baseline sensitivities for mycelial growth of 43 to 72 isolates of seven postharvest pathogens to natamycin and the resistance potential of Penicillium digitatum. Mean effective concentrations to inhibit mycelial growth by 50% (EC50 values), as determined by the spiral gradient method, were 0.90 μg/ml for Alternaria alternata, 0.76 μg/ml for Botrytis cinerea, 3.20 μg/ml for Geotrichum citri-aurantii, 0.17 μg/ml for Monilinia fructicola, 1.54 μg/ml for Penicillium digitatum, 1.14 μg/ml for P. expansum, and 0.48 μg/ml for Rhizopus stolonifer. Distributions of EC50 values for each pathogen were unimodal and mostly normal with no outliers detected. Natamycin was also inhibitory to spore germination with values for five of the species similar to those for mycelial growth. Microscopically, natamycin generally arrested spores at the pre-germination swelling stage. Mass platings of conidial mixtures of ten isolates of P. digitatum were inoculated on agar media with 2.5-log radial concentration gradients of natamycin or fludioxonil, and platings of G. citri-aurantii were executed on media amended with natamycin or propiconazole. No resistant isolates were observed for both species to natamycin or for G. citri-aurantii to propiconazole, whereas a resistance frequency of 4.5 x 10-6 to 3.1 x 10-6 was calculated for P. digitatum to fludioxonil. The wide spectrum of activity against different fungal pathogens and a low resistance potential support the registration of natamycin as a postharvest treatment and its integration into an integrated pest management program with other practices including sanitation and rotation of other fungicides with different modes of action.

scholarly journals FUNGAL PATHOGENS FOR BIOCONTROL OF INSECTS IN GREENHOUSES.

HortScience ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 260E-260
Author(s):  
Michael Brownbridge ◽  
Bruce L. Parker ◽  
Margaret Skinner
Keyword(s):  
Metarhizium Anisopliae ◽  
Fungal Pathogens ◽  
Green Peach Aphid ◽  
Western Flower Thrips ◽  
Great Promise ◽  
Verticillium Lecanii ◽  
Flower Thrips ◽  
Alternative Approaches ◽  
Further Development ◽  
Selection Of

Western flower thrips (WFT), green peach aphid (GPA) and sweet potato whitefly (SPWF) are major pests of the greenhouse industry. Chemical control of these pests is not desirable. Alternative approaches to pest management need to be developed. Entomopathogenic fungi hold great promise as sustainable biological control options. A broad range of indigenous fungal isolates have been screened for activity vs. WFT and GPA. Strains of Metarhizium anisopliae, Beauveria bassiana and Verticillium lecanii have been shown to be particularly effective. Plant and soil trials vs. WFT are now underway to permit selection of the best strains for further development. To date, assays vs. SPWF indicate that strains of Paecilomyces farinosus and B. bassiana are the most pathogenic.

Effect of Thawing on Growth of Staphylococcus Aureus in Frozen Convenience Food Items1

1975 ◽  
Vol 38 (6) ◽  
pp. 337-339 ◽  
Author(s):  
K. OSTOVAR ◽  
MARGARET J. BREMIER
Keyword(s):  
Staphylococcus Aureus ◽  
Egg Yolk ◽  
Frozen Foods ◽  
Convenience Food ◽  
Food Items ◽  
Poultry Products ◽  
Selective Agar ◽  
Seafood Products ◽  
Agar Media ◽  
Coagulase Positive Staphylococci

The appearance of convenience food items in the supermarkets and their consumption by wide segments of population has increased in recent years, and hence a study was done on presence of Staphylococcus aureus in these items and possible growth of the organism during defrosting of the foods. Using different selective agar media (Baird-Parker, Vogel-Johnson, Tellurite-polymyxin-egg yolk. and Mannitol-salt), various commercially available food items were examined. All suspected cultures were confirmed by coagulase test and Gram stain. Their enterotoxigenicity was also examined. Thawing the products at room temperature for 12 h generally resulted in a two-log increase in S. aureus population. Presence of S. aureus was observed in 18.3% of beef and poultry products; 12.5% of seafood products; and 8.3% of ready-to-eat frozen desserts. Most isolates produced types A or B enterotoxins. Of four selective agar media used. Baird-Parker was most efficient in isolating coagulase-positive staphylococci from frozen foods.

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