To obtain information on the sanitary of indoor environment in greenhouses used for shiitake cultivation, bacteria associated with larvae and imagoes of Sciaridae flies, pest to shiitake mushroom, were isolated and identified. A total of 1,048 bacterial colonies were isolated from the flies’ larvae and 984 bacterial colonies were isolated from the flies’ imagoes. Based on molecular analysis of the 16S rDNA sequence, Achromobacter xylosoxidans and Tetrathiobacter kashmirensis of β-proteobacteria, Enterobacter asburiae and Raoultella ornithinolytica of γ -proteobacteria, Curtobacterium sp. and Microbacterium thalassium of Actinobacteria, and Penibacillus taichungensis of Firmicutes were identified from the colonies of the flies’ larvae. While, Bacillus megaterium, B. thuringiensis, Lysinbacillus sphaericus and L. fusifomis of Firmicutes, Microbacterium thalassium and Citricoccus parietis of Actinobacteria, and Enterobacter asburiae of γ-proteobacteria were identified from the flies’ imagoes. Some of the isolated bacterial species were known be human pathogens. Overall, the results of this study suggested that mushroom fly carrying human pathogenic bacteria is one of sources impact on the sanitary of indoor environment of greenhouses used for shiitake cultivation.

To obtain information on the sanitary condition of indoor environment in greenhouses used for shiitake cultivation, bacteria associated with larvae and imagoes of Sciaridae flies, a pest to shiitake mushroom, were isolated and identified. A total of 1,048 bacterial colonies were isolated from the flies’ larvae and 984 bacterial colonies were isolated from the flies’ imagoes. Based on the molecular analysis of the 16S rDNA sequence, Achromobacter xylosoxidans and Tetrathiobacter kashmirensis of betaproteobacteria, Enterobacter asburiae and Raoultella ornithinolytica of gammaproteobacteria, Curtobacterium sp. and Microbacterium thalassium of Actinobacteria, and Penibacillus taichungensis of Firmicutes were identified from the colonies of the flies’ larvae. On the other hand, Bacillus megaterium, B. thuringiensis, Lysinbacillus sphaericus and L. fusifomis of Firmicutes, Microbacterium thalassium and Citricoccus parietis of Actinobacteria, and Enterobacter asburiae of gammaproteobacteria were identified from the flies’ imagoes. Some of the isolated bacterial species were known to be human pathogens. Overall, the results of this study suggested that mushroom fly carrying human pathogenic bacteria is one of factors affecting the sanitary of indoor environment of greenhouses used for shiitake cultivation.

This study was carried out to measure temperature, humidity, and bacterial concentration and species from the indoor air of a greenhouse used for shiitake cultivation. The highest level of humidity in the greenhouse was recorded at over 91.5% and the lowest humidity was recorded at 50% during 12 months. Temperature was between 5.1-30.5oC except for January. These results indicate that bacteria can survive in the indoor air of the greenhouse. Total bacterial concentration exceeded the Korean indoor air quality standard value (8.0 × 102 cfu/m3) in winter. A total of 13 genera and 17 species were isolated and identified from the indoor air of the greenhouse. Especially, 3 species (Kocuria rosea, Staphylococcus xylosus and Curtobacterium flaccumfaciens) have been reported to affect on human health. This is first report of airborne bacteria in a greenhouse used for shiitake cultivation.