• Analytical Science and Technology
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• v.26 no.4
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• pp.262-267
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• 2013

Gravitational field-flow fractionation (GrFFF) is a separation technique that utilizes earth's gravity as the external field. GrFFF is a convenient tool for the size and/or density-based separation of micron-sized particles of various origins. In this study, GrFFF was employed for size-based separation of oyster mushroom spores. Oyster mushroom spores have smooth surface and are of cylindrical to narrow kidney-shapes with 5 to 12 im in longer dimension and 3 to 4 im in shorter dimension, as was confirmed by optical microscope (OM). GrFFF conditions were optimized for separation and characterization of spores by varying the channel flow rate from 0.5 to 1 mL/min. During the GrFFF elution of the spores, 3 fractions were collected to confirm the growth of oyster mushroom spore. The collected fractions were incubated for 30 days in water to examine the influence of the size on the growth of the spores. Results suggested that the oyster mushroom spores collected at the middle part of the GrFFF fractogram grew faster than those collected at the beginning or at the end of the fractogram.

• Journal of Mushroom
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• v.12 no.2
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• pp.132-137
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• 2014

Green mold disease caused by Trichoderma species has recently caused considerable damage to oyster mushroom industries in Korea. This disease Trichoderma, Penicillium, Aspergillus, such as in (genus) to be included in a disease caused by a species that collectively the largest incidence and damage is caused by the pathogen Trichoderma genus. T. longibrachiatum, Trichoderma koningii, Trichoderma virens, T. hazianum, T. atroviride, and T. pseudokoningii were detected on oyster mushroom beds and, of them, T. virens, T. hazianum, T. longibrachiatum was the most frequently detected. The knowledge concerning physiological and ecological properties of Trichoderma spp. was essential for their effective control. T. longibrachiatum hyphal growth is very fast, spore formation, and, particularly well-chlamydospore formation characteristics, and reviews are dark green discoloration. T. koningii, fast mycelial growth, aerial hyphae and spores in aerial hyphae formation is concentrated. T. virens, especially if the color change caused by spore-forming, slow, late in infection, the more severe the damage is discovered. T. hazianum fast mycelial growth, white aerial hyphae and late turns dark green. After spore formation hyphae glob of white pustules or tufts on the top of the formation. T. atroviride. aerial hyphae usually the mycelial growth and spore formation in the unlikely event of the formation and smells similar to the smell of coconut is that. Fast T. pseudokoningii mycelial growth, spore formation is formed around the inoculation site, discoloration of the medium color and well formed chlamydospores.

• Journal of Mushroom
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• v.4 no.2
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• pp.53-56
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• 2006

The enormous production of spores by the fruitbodies in the cultivation of oyster mushrooms (Pleurotus ostreatus) is develop an allergy with symptoms similar to an "extrinsic allergic alveolitis (EEA)". the sporeless strain would noy only benefit health of mushroom workers but also reduce the risk of viral infections on the mushroom farms. For the development of a sporeless strain of P. ostreatus we used strain ASI 2069. This non-commercial strain is completely nonsporulating. We have recovered both nuclear types of strain ASI 2069 as monokaryons (hereafter referred to as neohaplonts) by protoplasting the mycelium. Crosses between neohaplonts and SSI's(single spore isolates) obtained from a sporulating commercial strain ASI 2180 yielded fruitbodies that isolated 128 strains. 13 excellent strains are selected from 30 bred strains by quality of fruitbodies and spore number. Among 13 excellent strains, G192 strain is chose finally to high yield and sporelessness.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.376-381
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• 1992

In order to study the effect of modified atmosphere storage on extending shelf life of mushrooms, oyster mushroom and Shiitake were wrapped with polyethylene film (PE, $50\;{\mu}m$), and stored at $0.5^{\circ}C$. Mushrooms packed with conventional hardboard box (4kg) lost marketability within $5{\sim}6$ days due to weight loss, shrinkage, browning, spore formation and/or mycellium growth. PE-packing could prevent or retard the deterioration of the mushrooms in the aspects of appearance, texture, discoloration, and microbial contamination. This situation can be best characterized by the reduced respiration rate resulted from the elevated level of carbon dioxide and the reduced level of oxygen in the bag. Although the appearance of the oyster mushroom was maintained for one month, its shelf life was limited to 15 days because of tissue softening. Discoloration of the pileus of shiitake mushroom appears to be the most important factor to determine its marketability. For example, extension of shelf life of Dongo was limited to 15 days, principally due to the browning of the pileus. Shelf life of Hawgo whose color of the pileus changed little over the experimental period, however, could be extened to more than one month.

• Journal of Mushroom
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• v.2 no.1
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• pp.4-9
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• 2004

This study was carried out to investigate effect of NaCl treatment on growth oyster mushroom and Trichoderma spp. on PDA and in rice straws. We also investigated the possibility of oyster mushroom cultivation using rice straw harvested from the reclaimed land having been drained sea water. Mycelial growth of oyster mushroom was increased by treatment of 0.2% NaCl but decreased by treatment of the higher concentration of NaCl. In the case of the mycelial growth on PDA of Trichoderma spp., no change was found in 0.5%~1.0% NaCl, but decreased in the range of 1.0%~3.0% NaCl and drastically decreased at 5.0% NaCl. In the rice straws treated with different concentration of NaCl solution, mycelial growth of oyster mushroom showed almost same result compare to PDA. The spore formation of Trichoderma mould was almost same in both 0% and 0.3% NaCl, decreased in 0.5% and was not found spores in the higher concentration of NaCl. As increasing salt concentration in the rice straws, the NaO contents were increased. The $K_2O$ contents were decreased before and after sterilization. The moisture content of rice straws showed no difference by treatment of 3.0% NaCl but decreased the moisture by treatment of 5.0% NaCl. No pH change was found in the rice straws treated with NaCl. Mushroom yield in the rice straw of reclaimed land was a little higher than that of normal paddy land straw. The duration of primordium formation was not affected by NaCl concentration in rice straws. The yield of fruiting body in 0.3% NaCl treatment was 2,700kg, which was almost same to non-treated plot, but decreased in 0.5% NaCl. EC value of soaking water after submerging rice straw was higher than before, but NaO content was not changed at both condition.

• The Korean Journal of Mycology
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• v.38 no.1
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• pp.69-74
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• 2010

The 2 strains of Pleurotus ostreatus showing very severe and mild symptom of brown blotch were selected, and their F1 hybrid strains were made by mating of their single spore isolates. Hydrophobicity of fruiting body surface and brown blotch severity of the parental and their 11 F1 hybrid strains showing different level of severity of brown blotch were determined. Correlation coefficient (R) between disease severity and hydrophobicity were 0.68 and 0.70 on two independent experiments. Correlation coefficient between disease severity and disease incidence that was determined in the oyster mushroom farm were 0.46 and 0.52 on two independent experiments. When GFP-tagged Pseudomonas tolaasii was monitored with confocal microscope on cap surface of fruiting body, more cells of the pathogen were clustered on the severe strain than the mild strain, which indicates that the bacterial pathogen proliferates more on the severe strain. These results suggest that hydrophobicity of oyster mushroom fruiting body affects disease severity of the brown blotch disease; the longer the bacterial suspension stays on fruiting body surface more severe symptom of the blotch develops.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1079-1085
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• 2003

Modified atmosphere packaging was applied to oyster mushrooms (Pleurotus ostreatus) to study the effect of storage temperatures and packaging materialso. Whole mushrooms (200g) were package with polyethylene film $(PE,\;60{\mu}m\;thickness)$, ethylene vinyl acetate (EVA), or ceramic film (containing 5% zeolite) and stored at 0, 5, 10 and $20^{\circ}C$. Weight loss, color, firmness, gas composition $(O_2,\;CO_2)$ inside the film package and ethanol content in the tissue of MA packaged mushrooms were examined. Mushroom that were packed unwrapped in a conventional hardboard box (2 kg) lost marketability at a very early stage of storage due to weight loss, shrinkage, browning, and spore formation. During storage, film packaging prevented or retarded the deterioration of the mushrooms in the aspects of appearance, texture, and discoloration. Firmness slightly decreased with storage time. Total color difference was much higher in the control than in the film-packaged mushroom and rapidly increased at the early of storage. Correlation analysis showed a high correlation between total color difference and b values. These results were characterized by the reduced respiration rate resulting from elevated carbon dioxide and reduced oxygen levels in the package. At all storage temperatures, ethanol content in the tissue increased slightly at the early part of storage and rose considerably towards the end of the storage period. Ethanol content in the oyster mushrooms was higher in the stipe than in pileus tissues. The shelf life of the oyster mushrooms was about $8{\sim}11$ days at $0^{\circ}C$, about $4{\sim}6$ day at $5^{\circ}C$, about $2{\sim}3$ days at $10^{\circ}C$, and about $1{\sim}2$ days at $20^{\circ}C$.

• Journal of Mushroom
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• v.4 no.2
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• pp.48-52
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• 2006

Oyster mushroom, Pleurotus ostreatus is bifactorial heterothallism. Single basidiospore isolates from fruiting bodies are homokaryotic and self-sterile. However, we found that homokaryons derived from some strains of P. ostreatus could develop fruiting bodies with two different types. One hundred and two isolates out of 155 monospore isolates formed fruiting bodies (65.8%). First group did not have only mature or sporulating fruiting bodies but also clamp connections, which initial isolate also did not present clamp connections (Abortive homokaryotic fruiting, AHF). Second group had developed fruiting bodies with clamp connections even though initial homokaryotic colony did not form clamp connections (Pseudo- homokaryotic fruiting, PHF). The mycelial colonies derived from PHF by tissue culture formed clamp connections, while mycelial colonies of AHF lacked them. We obtained 535 PHF and 79 AHF inter-strain hybrids among 8 strains of P. ostreatus by hyphal anastomosis. The fruiting body yield of PHF group is higher than that of AHF group in bottle cultivation. A preselection of single spore isolates for fertility would save labour in strain improvement of P. ostreatus.

• Journal of Mushroom
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• v.21 no.4
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• pp.254-260
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• 2023

The characteristics and spore production of Gonji7ho, Bunhong, and Sunjung fruiting bodies were assessed at different growth stages. The shape of the Pleurotus species fruiting body starts out short and small, then takes on a typical mushroom shape as it grows. Gonji7ho has a long stalk, Bunhong has a short stalk and a wide cap, and Sunjung's cap and stalk dimensions are intermediate. Each variety displayed deep color at the beginning of growth but became steadily lighter with continued growth. The shape of the linkage between the mushroom stalk and cap changed from an initial central position to a lateral position after the growing stage. Gonji7ho cap diameter increased 7-fold from 15.5 mm (5 days of growth) to 37.9 mm (9 days of growth). Growth rates for each growth day measured using the growth percentage of the previous day were 285.5% (5 → 6th day), 182.2% (6 → 7th day), 129.4% (7 → 8th day), and 103.8% (8 → 9th day). This trend was also observed in Bunhong and Sunjung, but Bunhong's growth rate was more rapid (4.9 fold on day 6, 2.7 fold on day 7) and continued to increase through day 9. Harvest yield, which is of greatest interest to farmers, displayed a similar trend spanning the growth period, as did cap diameter. Gonji7ho harvest yield increased rapidly until day 7 of growth (more than 177%), then growth slowed down beginning around day 8, and further decreased on day 9 (98%). Similar trends were observed in Bunhong and Sunjung. Bunhong showed characteristic rapid growth in harvest yield (4.9 fold compared to the previous day on day 6 and 2.7 fold on day 7), and the increase continued through day 9. A decrease in mushroom harvest yield commonly seen in the late growth stage is thought to be due to the death of some mushrooms and decomposition of cap tissue. Basidiospore content increased with number of growth days but decreased after day 8. Gonji7ho yielded the highest production on day 7 of growth, coinciding with harvest time, with 209,000,000 spores. This trend was also observed in Bunhong and Sunjung. These results will provide researchers with basal data and guide farmers in selecting the optimal harvest day.