Dataset Information

Fungicide Sensitivity and Characterization of Cobweb Disease on a Pleurotus eryngii Mushroom Crop Caused by Cladobotryum mycophilum.

ABSTRACT: In 2009-2010, unusual symptoms were observed on Pleurotus eryngii grown in mushroom farms in Gyeongnam Province, Republic of Korea. One of the main symptoms was a cobweb-like growth of fungal mycelia over the surface of the mushroom. The colonies on the surface rapidly overwhelmed the mushrooms and developed several spores within 3-4 days. The colonized surface turned pale brown or yellow. The fruit body eventually turned dark brown and became rancid. Koch's postulates were completed by spraying and spotting using isolated strains. The phylogenetic tree obtained from the internal transcribed spacer sequence analysis showed that the isolated fungal pathogen corresponded to Cladobotryum mycophilum (99.5%). In the fungicide sensitivity tests, the ED50 values for the isolate with respect to benomyl and carbendazim were from 0.29 to 0.31 ppm. Benzimidazole fungicides were most effective against C. mycophilum, a causal agent of cobweb disease in P. eryngii.

SUBMITTER: Kim MK

PROVIDER: S-EPMC4174831 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Fungicide Sensitivity and Characterization of Cobweb Disease on a Pleurotus eryngii Mushroom Crop Caused by Cladobotryum mycophilum.

Kim Min Keun MK Seuk Su Won SW Lee Young Han YH Kim Hye Ran HR Cho Kye Man KM

The plant pathology journal 20140301 1

In 2009-2010, unusual symptoms were observed on Pleurotus eryngii grown in mushroom farms in Gyeongnam Province, Republic of Korea. One of the main symptoms was a cobweb-like growth of fungal mycelia over the surface of the mushroom. The colonies on the surface rapidly overwhelmed the mushrooms and developed several spores within 3-4 days. The colonized surface turned pale brown or yellow. The fruit body eventually turned dark brown and became rancid. Koch's postulates were completed by spraying ...[more]

PMID: 25288989

Similar Datasets

Project description:Aflatoxin B1 (AFB1) is the most harmful mycotoxin that occurs as natural contaminant of agricultural commodities, particularly maize. Practical solutions for detoxification of contaminated staples and reduction of agricultural wastes are scarce. We investigated the capability of the white-rot and edible fungus Plerotus eryngii (king oyster mushroom) to degrade AFB1 both in vitro and in a laboratory-scale mushroom cultivation, using a substrate similar to that routinely used in mushroom farms. In malt extract broth, degradation of AFB1 (500 ng/mL) by nine isolates of P. eryngii ranged from 81 to 99% after 10 days growth, and reached 100% for all isolates after 30 days. The growth of P. eryngii on solid medium (malt extract-agar, MEA) was significantly reduced at concentrations of AFB1 500 ng/mL or higher. However, the addition of 5% wheat straw to the culture medium increased the tolerance of P. eryngii to AFB1 and no inhibition was observed at a AFB1 content of 500 ng/mL; degradation of AFB1 in MEA supplemented with 5% wheat straw and 2.5% (w/v) maize flour was 71-94% after 30 days of growth. Further, AFB1 degradation by P. eryngii strain ITEM 13681 was tested in a laboratory-scale mushroom cultivation. The mushroom growth medium contained 25% (w/w) of maize spiked with AFB1 to the final content of 128 μg/kg. Pleurotus eryngii degraded up to 86% of the AFB1 in 28 days, with no significant reduction of either biological efficiency or mushroom yield. Neither the biomass produced on the mushroom substrate nor the mature basidiocarps contained detectable levels of AFB1 or its metabolite aflatoxicol, thus ruling out the translocation of these toxins through the fungal thallus. These findings make a contribution towards the development of a novel technology for remediation of AFB1- contaminated corn through the exploitation of the degradative capability of P. eryngii and its bioconversion into high nutritional value material intended for feed production.

Project description:Listeria monocytogenes is a major foodborne pathogen that is well-known for its high mortality rate upon infection. In recent years, the edible mushroom has also been found to be an important source of L. monocytogenes, but the contamination sources in Pleurotus eryngii (the king oyster mushroom) were unclear. In this study, a total of 203 edible mushrooms and environmental samples from four P. eryngii production plants were obtained. As a result, 29 samples (14.3%) were positive for L. monocytogenes, including eight mushroom samples (13.3%, 8/60) and 21 associated environmental samples (14.7%, 21/143). The contamination of L. monocytogenes in plants A and B was more severe and was likely to originate from the mycelium stimulation machine. The isolates belonged to serogroups II.1 (4b-4d-4e), I.1 (1/2a-3a), and I.2 (1/2c-3c), and multilocus sequence typing (MLST) revealed that these L. monocytogenes strains belonged to five different sequence types (ST3, ST121, ST9, ST87, and ST224). The ST121 and ST3 isolates were only found in plants A and B, respectively. The isolates were carried by hly (29/29, 100%), inlB (23/29, 79.3%), inlA (29/29, 100%), inlC (29/29, 100%), inlJ (29/29, 100%), actA (19/29, 65.5%), iap (29/29, 100%), plcA (26/29, 100%), plcB (29/29, 100%), prfA (27/29, 93.1%), and mpl (29/29, 100%). Further study of inlA sequencing showed that 65.5% of strains (19/29) contained full-length InlA that was required for host cell invasion, whereas the mutation led to premature stop codons (PMSCs) at position 492 (type 6) on inlA alleles. All isolates in this survey were sensitive to gentamicin, kanamycin, sulbactam/ampicillin, trimethoprim-sulfamethoxazole, tetracycline, and doxycycline. The drug with the highest resistance is rifampicin (37.9%), followed by penicillin (24.1%) and ciprofloxacin (10.3%). Most multiply resistant strains are isolated from raw materials and equipment of the P. eryngii processing lines. Our study reflects the contamination patterns and potential risk of L. monocytogenes infection in P. eryngii production plants. The persistence of specific L. monocytogenes isolates (such as ST121 and ST3) may assist with contamination. In accordance with these results, the control of L. monocytogenes should focus on the environmental materials, especially in the mycelium stimulation stage. However, effective Listeria monitoring programs will allow for the improved development of Listeria control measures to minimize cross-contamination in the processing of P. eryngii.

Dataset Information

Fungicide Sensitivity and Characterization of Cobweb Disease on a Pleurotus eryngii Mushroom Crop Caused by Cladobotryum mycophilum.

Publications

Fungicide Sensitivity and Characterization of Cobweb Disease on a Pleurotus eryngii Mushroom Crop Caused by Cladobotryum mycophilum.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets