Resistance of Pre- and Post-epidemic Strains of Agaricus bisporus to Trichoderma aggressivum f. aggressivum

Since the early 1990s, the epidemic of green mold on the cultivated mushroom Agaricus bisporus in North America has been caused by Trichoderma aggressivum f. aggressivum. The findings of earlier research suggested that the microevolutionary emergence of T. aggressivum f. aggressivum coincided with the onset of the epidemic. This hypothesis was tested further by determining the disease susceptibility of mushroom strains grown widely before the epidemic manifested. The results of complementary methods of analysis, which entailed a grain protection assay and cropping trials, established that two pre-epidemic strains were more susceptible to green mold than three post-epidemic strains being cultivated at the time of the epidemic. Thus, if T. aggressivum f. aggressivum had been present within cultivated mushrooms prior to the epidemic, it should have been detected. It still appears to be true that T. aggressivum f. aggressivum emerged during the 1990s in a manner that remains unclear.

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PCR-Based Genotyping of Epidemic and PreepidemicTrichoderma Isolates Associated with Green Mold ofAgaricus bisporus

Applied and Environmental Microbiology ◽

10.1128/aem.65.6.2674-2678.1999 ◽

1999 ◽

Vol 65 (6) ◽

pp. 2674-2678 ◽

Cited By ~ 21

Author(s):

X. Chen ◽

C. P. Romaine ◽

Q. Tan ◽

B. Schlagnhaufer ◽

M. D. Ospina-Giraldo ◽

...

Keyword(s):

Genetic Variation ◽

North America ◽

Agaricus Bisporus ◽

Rapd Markers ◽

Rapd Analysis ◽

Pcr Amplification ◽

Green Mold ◽

Rapd Pcr ◽

Cultivated Mushroom ◽

Highly Virulent

ABSTRACT We used randomly amplified polymorphic DNA (RAPD)-PCR to estimate genetic variation among isolates of Trichoderma associated with green mold on the cultivated mushroom Agaricus bisporus. Of 83 isolates examined, 66 were sampled during the recent green mold epidemic, while the remaining 17 isolates were collected just prior to the epidemic and date back to the 1950s.Trichoderma harzianum biotype 4 was identified by RAPD analysis as the cause of almost 90% of the epidemic-related episodes of green mold occurring in the major commercial mushroom-growing region in North America. Biotype 4 was more closely allied to T. harzianum biotype 2, the predominant pathogenic genotype in Europe, than to the less pathogenic biotype 1 and Trichoderma atroviride (formerly T. harzianum biotype 3). No variation in the RAPD patterns was observed among the isolates within biotype 2 or 4, suggesting that the two pathogenic biotypes were populations containing single clones. Considerable genetic variation, however, was noted among isolates of biotype 1 and T. atroviride from Europe. Biotype 4 was not represented by the preepidemic isolates of Trichoderma as determined by RAPD markers and PCR amplification of an arbitrary DNA sequence unique to the genomes of biotypes 2 and 4. Our findings suggest that the onset of the green mold epidemic in North America resulted from the recent introduction of a highly virulent genotype of the pathogen into cultivated mushrooms.

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BseGI Restriction of the Polymerase Chain Reaction Amplicon Th444 Is Required to Distinguish Biotypes of Trichoderma aggressivum Causing Serious Losses in Mushroom (Agaricus bisporus) Production

HortScience ◽

10.21273/hortsci.45.12.1910 ◽

2010 ◽

Vol 45 (12) ◽

pp. 1910-1911

Author(s):

Mirosława Staniaszek ◽

Katarzyna Szajko ◽

Zbigniew Uliński ◽

Magdalena Szczech ◽

Waldemar Marczewski

Keyword(s):

Polymerase Chain Reaction ◽

Agaricus Bisporus ◽

Polymerase Chain Reaction Amplicon ◽

Chain Reaction ◽

Restriction Fragments ◽

Green Mold ◽

Cultivated Mushroom ◽

Polymerase Chain ◽

Serious Disease ◽

Reference Strains

Green mold is a serious disease of the cultivated mushroom causing losses in production of economical importance. In the present study, digestion of a Th444 amplicon with endonuclease BseGI was useful to discriminate Trichoderma aggressivum f. aggressivum (T.a.f.a) from the T. aggressivum f. europeanum (T.a.f.e.). The informative restriction fragments of 260 and 300 bp were revealed in the corresponding reference strains T.a.f.a. and T.a.f.e. The 300-bp marker was found in all 28 Polish mushroom isolates tested.

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Lecanicillium dimorphum. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056401564 ◽

2003 ◽

Author(s):

R. Zare

Keyword(s):

Great Britain ◽

North America ◽

Leaf Litter ◽

Geographical Distribution ◽

Fungal Pathogen ◽

Acer Saccharum ◽

Agaricus Bisporus ◽

Puccinia Coronata ◽

Cultivated Mushroom

Abstract A description is provided for Lecanicillium dimorphum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Occurs mainly on the cultivated mushroom, Agaricus bisporus (CHEN et al., 1985). It is not a serious fungal pathogen. HOSTS: Agaricus bisporus and Puccinia coronata; leaf litter of Acer saccharum; also isolated from soil. GEOGRAPHICAL DISTRIBUTION: NORTH AMERICA: USA. ASIA: China, Iran, Israel. EUROPE: Germany, Great Britain, Netherlands. TRANSMISSION: Soil- and air-borne.

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Verticillium disease or "dry bubble" of cultivated mushrooms: the Agaricus bisporus lectin recognizes and binds the Verticillium fungicola cell wall glucogalactomannan

Canadian Journal of Microbiology ◽

10.1139/w04-047 ◽

2004 ◽

Vol 50 (9) ◽

pp. 729-735 ◽

Cited By ~ 26

Author(s):

Dolores Bernardo ◽

Amelia Pérez Cabo ◽

Monique Novaes-Ledieu ◽

Concepción García Mendoza

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Agaricus Bisporus ◽

Immunofluorescence Microscopy ◽

Fruit Body ◽

Vegetative Mycelium ◽

Verticillium Fungicola ◽

Dry Bubble ◽

Cultivated Mushroom ◽

Cultivated Mushrooms

The step of recognition and (or) binding for the development of the disease of the cultivated mushroom Agaricus bisporus by the mycoparasite Verticillium fungicola was studied by several approaches: agglutination of V. fungicola germinated spores by an A. bisporus extract from fruit body cell walls, immunofluorescence microscopy of A. bisporus hyphae from fruit bodies and vegetative mycelia pretreated with purified V. fungicola cell wall glucogalactomannan, and finally, by hemagglutination experiments carried out with an A. bisporus fruit body lectin in the presence and absence of the same glucogalactomannan. Hemagglutinating activity of the purified A. bisporus fruit body lectin was clearly inhibited by the V. fungicola glucogalactomannan, whereas in the A. bisporus vegetative mycelium such lectin was not encountered. All the results obtained make evident the recognition and binding of the A. bisporus fruit body lectin to the V. fungicola cell wall glucogalactomannan, clarifying why the mushrooms, but not the vegetative mycelium, become diseased.Key words: Agaricus bisporus lectin, Verticillium fungicola glucogalactomannan, mycoparasitism.

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