• Journal of Mushroom
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• v.4 no.4
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• pp.135-143
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• 2006

We have investigated cultural circumstance and given condition of king oyster mushroom(Pleurotus eryngii) growing farmer. We collected many pathogens from King oyster mushroom growing farmer and identified with chemicobiological test and microscope. Most of investigated farmers neglected their's growing room cleaning and washing, after harvesting At pin-heading induction time, humidity degree in growing room was kept of high level and Air ventilation volume was so little that fruit-body formation ratio was low. The collected pathogens were twenty eight strains and identified with Pseudomonas sp., Trichoderma sp. mostly. During the spawn running time and pin-heading induction time, contamination by Trichoderma sp. occurred mostly, but during the fruit-body growing time, contamination by Pseudomonas sp., Erwinia sp. etc, occurred.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.1
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• pp.8-15
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• 2010

An experiment was conducted to evaluate the biologically adverse effect of increased carbon dioxide in seawater on marine bacteria, Vibrio fischeri. We measured the bioluminescence and cell density at every 6 hours for 24 hours of the whole incubation period after exposing test microbes to a range of $CO_2$ concentration such as 380(Control), 1,000, 3,000, 10,000 and 30,000 ppm, respectively. Significant effect on relative luminescence(RLU) of V. fischeri was observed in treatments with $CO_2$ concentration higher than 3,000 ppm at t=12 h. However, the difference of RLU among treatments significantly decreased with the incubation time until t=24 h. Similar trend was observed for the variation of cell density, which was measured as optical density using spectrophotometer. The results showed that a significant relationship between $CO_2$ concentration and bioluminescence of test microbes was observed for the mean time. However, the inhibition of relative bioluminescence and also cell density could be recovered at the concentration levels higher than 3,000 ppm. The dissolved $CO_2$ can be absorbed directly by cell and it can decrease the intracellular pH. Our results implied that microbes might be adversely affected at the initial growing phase by increased $CO_2$. However, they could adapt by increasing ion transport including bicarbonate and then could make their pH back to normal level. Results of this study could be supported to understand the possible influence on marine bacteria by atmospheric increase of $CO_2$ in near future and also by released $CO_2$ during the marine $CO_2$ sequestration activity.