Fungicide resistance among Cladobotryum spp. - Causal agents of cobweb disease of the edible mushroom Agaricus bisporus

Department of Plant Pathology and Microbiology, Horticulture Research International, Wellesbourne, Warwick CV35 9EF, UK
Mycological Research (Impact Factor: 2.81). 03/2000; 104(3):357-364. DOI: 10.1017/S0953756299001197
Source: OAI


A survey of fungicide resistance among isolates of the mushroom pathogens Cladobotryum mycophilum and C. dendroides Types I and II was undertaken, with respect to the active ingredients thiabendazole, carbendazim (benzimidazoles) and prochloraz manganese following an epidemic in Britain and Ireland in 1994/95. The majority of isolates (41/57) were strongly resistant to thiabendazole (ED50 > 200 ppm) and were exclusively C. dendroides Type II. All C. mycophilum and C. dendroides Type I isolates, and four C. dendroides Type II isolates, were weakly resistant to thiabendazole (ED50 1–10 ppm). Thiabendazole-resistant C. dendroides Type II isolates were only weakly resistant to carbendazim (ED50 2–10 ppm) and isolates which were weakly resistant to thiabendazole were carbendazim-sensitive (ED50 < 1 ppm), demonstrating a lack of complete cross resistance between these two benzimidazole fungicides. The ED50 values for all isolates with respect to prochloraz manganese ranged from 0.14 to 7.8 ppm. Benzimidazole resistance was considered to have been an important factor influencing the severity of the 1994/95 cobweb epidemic but 25% of isolates collected were benzimidazole sensitive.

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    • "produce masses of spores. Moreover, some species of Cladobotryum from A. bisporus were observed to be fungicide resistant [16] and fungicide application is restricted for edible mushrooms due to its residual toxicity. Disinfection using near-UV irradiation has been described as an effective method for reducing pathogenic fungi and bacteria in mushroom growing spaces [17]. "
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    ABSTRACT: Four Cladobotryum isolates were collected from four different commercially grown mushroom types infected with cobweb disease in Cheongdo-gun and Chilgok-gun of Gyeongbuk Province, Korea in 2010. The isolates were identified as C. mycophilum from Agaricus bisporus and Pleurotus eryngii, C. varium from Flammulina velutipes and Hypsizygus marmoreus. The cultural characteristics of the four isolates were investigated using potato dextrose agar (PDA) media under nine different temperatures ranging from 5~32℃. Rapid growth of the isolates to colony diameters of 47~82 mm was observed at conditions of 18~22℃. No growth was observed at 32℃. C. mycophilum produced a yellowish red pigment while C. varium produced a cream colored pigment after cultivation for 25 days on PDA. Phylogenetic analysis of the internal transcribed spacer region and partial 28S rDNA from the four isolates confirmed they were C. mycophilum and C. varium. Cross pathogenicity tests revealed that the two isolates of C. mycophilum were highly pathogenic toward three mushroom types, but not toward H. marmoreus. The two isolates of C. varium were less pathogenic than those of C. mycophilum, but were pathogenic toward all mushroom types evaluated.
    Mycobiology 09/2012; 40(3):189-94. DOI:10.5941/MYCO.2012.40.3.189 · 0.51 Impact Factor
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    • "Numerous species of Cladobotryum cause cobweb disease of A. bisporus (Grogan and Gaze 2000) including C. dendroides , C. mycophilum, C. varium, C. multiseptatum and C. verticillatum (Adie et al. 2006; McKay et al. 1999). In recent years, cobweb diseases have been widespread and caused serious losses in Europe, the USA and Australia (Gaze and Fletcher 2008). "
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    ABSTRACT: This report is the first of cobweb disease on Agaricus bisporus in Korea. Cobweb on both fruit bodies and casing soils were observed on several mushroom farms in Gyeongbuk Province, Korea. Classical and molecular characterization indicated that the causal agent is Cladobotryum mycophilum. The isolated fungus was used to inoculate fruiting bodies of A. bisporus and caused the same symptoms. KeywordsMushroom- Agaricus bisporus -Cobweb disease- Cladobotryum mycophilum
    Journal of General Plant Pathology 06/2010; 76(3):232-235. DOI:10.1007/s10327-010-0236-3 · 0.97 Impact Factor
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    • "Casing inoculation was done by spore suspension spraying (approximately 10 6 conidia/ml) three days after casing. The bags were incubated at 25 o C during spawn-running of casing (for seven days) and then temperature was decreased to 18 o C (Grogan et al., 2000 "
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    ABSTRACT: Twenty isolates were isolated from diseased fruiting bodies of Agaricus bisporus collected from Serbian mushroom farms during 2003-2007. The isolates formed white, cottony, aerial colonies on agar media. With age, conidia and colonies turned yellow and redish.Pathogenicity of these isolates was confirmed by inoculation of harvested basidiomes of A. bisporus and by casing inoculation. Symptoms similar to natural infection were recorded. Based on pathogenicity tests and morphological characteristics, the isolates were identified as Cladobotryum dendroides (Bulliard : Fries) W. Gams & Hoozemans.
    01/2008; 23(3). DOI:10.2298/PIF0803175P
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