• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.531-537
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• 1998

Forest green mold incidence rate, extent of damage according to the inoculation periods, and its cultural characteristics were observed in the automatic cultural system of the winter mushroom, Flammulina velutipes. The incidence rate of the forest green mold was 7.7% in early cultivation stage and slowly increased to 14.9% in harvest stage. When the forest green mold was inoculated at cultural period, the rate was recorded at 100%, but the extent of the damage increased up to 40% (+++). There was also 100% incidence rate at early pinheading time, whereas the yield of mushroom decreased to ++ $(10{\sim}39%)$. The rate of forest green mold was greatly decreased to 34.4% at 10 days after pinheading, and its damage extent was also below 10%. A pathogen to infect the winter mushroom was identified as Trichoderma pseudokoningii. It's optimum temperature for mycelial growth is $25^{\circ}C$, and it grew 2.6 times faster than that of F. velutipes. The mycelial color of T. pseudokoningii was pale yellow or olivaceous in shades on PDA medium. Phialospore was one celled, and ellipsodal or obovoid, smooth walled, and measured $1.3{\sim}3.0{\times}1.0{\sim}2.5\;{\mu}m$. It aggregated in small heads at the tips of the phialides. The phialides were $3.2{\sim}9.2{\times}2.0{\sim}5.5\;{\mu}m$ and were of bowling pin type, solitary and alternate or more irregularly disposed at the conidiophore apex, T. pseudokoningii depressed the F. velutipes growth at the crossing cultivation when they were simultaneously. FV 4-1 (F. velutipes) cultivar was less depressed by T. pseudokoningii, but had a lower cross growth rate than the other four cultivars.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.51-53
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• 2008

To utilize edible red algae paper for food packaging, red algae paper coated with green tea extract or catechin was prepared and microbial growth in bread wrapped with the paper was determined during storage. The paper coated with green tea extract or catechin had antimicrobial activity against Escherichia coli. Packaging of bread with the red algae paper coated with green tea extract or catechin decreased the populations of total aerobic bacteria and yeast and mold after 2 days of storage by 0.41 and 0.63 log CFU/g, respectively, compared to the control. These results suggest that bread can be packaged by edible red algae paper coated with green tea extract or catechin, resulting in inhibit microbial growth during storage.

• Mycobiology
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• v.30 no.1
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• pp.37-40
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• 2002

The susceptibility of radiata pine sapwood to fungal attack and the ability of selected fungicides to control colonization of sapstain and mold fungi on green radiata pine sapwood were evaluated. Radiata pine sapwood was highly susceptible to fungal staining, suggesting that prompt application of fungicides after sawing is essential for preventing fungal colonization. The ability of commercial fungicides to prevent fungal discoloration on radiata pine sapwood was assessed using an accelerated 6-week test on small samples in the laboratory, and in field tests using bulk-piled boards exposed outdoors for 6 weeks during summer rainy season. In laboratory tests, Hylite extra provided excellent protection against fungal discoloration even at the lowest concentrations. Hylite clear, Britewood S, and NP-1 Plus provided good short-term protection(2 to 4 weeks), but higher chemical loadings were, required for long-term protection(6 weeks). Woodguard produced little or no protection over the test periods. In field tests, Kathon 893 provided markedly superior protection at the concentration of 0.5 percent or higher. NP-1 Plus provided relatively good protection at all concentrations evaluated. Hylite extra was effective only for short-term protection(2 to 4 weeks) at all concentrations tested, but higher solution strengths were needed for longterm protection.

• Research in Plant Disease
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• v.17 no.3
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• pp.386-390
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• 2011

In June 2011, walnuts (Juglans regia) from orchards in Kimcheon and Muan, in southern Korea, were found to exhibit downy mildew-like symptoms of a foliar disease. Whitish polygonal efflorescence was produced on the abaxial surface of affected leaves and discolored light green blotches on the corresponding adaxial surfaces. In the later stage of disease development, diseased tissues collapsed and became necrotic. Based on morphological and cultural characteristics, the causal fungus was identified as Microstroma juglandis. The sequence of ITS rDNA of the present isolate showed 100% similarity with those of M. juglandis obtained from GenBank databases, thus confirming its identity. Pathogenicity tests were conducted on leaves of walnut seedlings, fulfilling Koch's postulates. The disease has been previously reported in North America, Europe, Oceania and some western Asia. This is the first report of downy leaf spot on walnuts in East Asia.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.674-683
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• 2019

Some species of the Trichoderma genus are reported as the major problem in oak wood mushroom production in Korea. In spite of economic loss by the fungi, scientific information on airborne Trichoderma species is not much available. To generate information for disease management development we analyzed airborne Trichoderma. A total of 1,063 fungal isolates were purely obtained from indoor air sampling of cultivation houses used for oak wood mushroom using sawdust media. Among the obtained isolates, 248 isolates were identified as Trichoderma fungi including T. harzianum, T. atroviride, T. citrinoviride, and T. pseudokoningii, by morphological and molecular analysis. T. harzianum was dominant among the four identified species. All the four Trichoderma species grew fast on solid nutrient media tested (potato dextrose agar [PDA], malt extract agar [MEA], Czapek's Dox + yeast extract agar [CYA] and cornmeal dextrose agar). Compact mycelia growth and mass spore production were better on PDA and CYA. In addition, T. harzianum and T. citrinoviride formed greenish and yellowish mycelium and spores on PDA and CYA. Greenish and yellowish pigment was saturated into PDA only by T. pseudokoningii. These four Trichoderma species could produce extracellular enzymes of sawdust substrate degradation such as β-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease. Their mycelia inhibited the growth of oak wood mushroom mycelia of two tested cultivars on dual culture assay. Among of eleven antifungal agents tested, benomyl was the best to inhibit the growth of the four Trichoderma species. Our results demonstrate that the airborne Trichoderma fungi need to be properly managed in the cultivation houses for safe mushroom production.

• Journal of Environmental Science International
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• v.24 no.11
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• pp.1363-1370
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• 2015

This study was aimed to determine effects of soil organic amendment as plant growing media component on restoration of planting ground. The changes of soil physical and chemical properties and germination and growth of kentucky bluegrass (Poa pratensis L.) were investigated. For treatments, soil was excavated at depth of 0-50 cm (referred as $S_1$) and at depth of 50-100 cm (referred as $S_2$). Then the half amount of $S_1$ soil was mixed with the soil organic amendment (coir dust 40% (v/v), bottom ash 25%, leaf mold 25%, vermiculite 5%, carbonized rice hull 5%) at a rate of 6% (v/v) (referred as $S_1CC$) and also the half amount of $S_2$ soil was mixed with the soil organic amendment at a rate of 6% (v/v) (referred as $S_2CC$) on pot in a 16 cm diameter and 14 cm height. The experiment was replicated 3 times with 3 pots per replication in randomized block design, and 100 seeds were planted per pot. In results, there was no significant difference in soil pH among the treatments with a slight decrease in soil hydraulic conductivity. However, in the $S_1CC$ treatment, positive increases in soil chemical properties, including electrical conductivity, organic matter, phosphoric acid, total nitrogen, exchangeable cation, and cation exchange capacity. Also, the germination rate, plant height, and number of leaves were higher in the $S_1CC$ treatment than those in other treatments. These results suggest that the addition of organic amendment to the soil at depth of 0-50 cm might be proper for restoring planting ground.