• Mycobiology
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• v.36 no.4
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• pp.199-202
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• 2008

Inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. This fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (Betula spp). The dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. Chaga are a folk remedy in Russia, reflecting the circumboreal distribution of I. obliquus in boreal forest ecosystems on Betula spp. and in meridional mountain forests on beech (Fagus spp.) in Russia, Scandinavia, Central Europe, and Eastern Europe. Distribution at lower latitudes in Western and Southern Europe, Northern America, Asia, Japan, and Korea is rare. Infected trees grow for many years without several symptoms of decline. The infection can penetrate through stem injuries with exterior sterile conks developing later. In the Czech Republic, cinder conk is found on birches inhabiting peat bogs and in mountain areas with a colder and more humid climate, although it is widespread in other broad leaved species over the Czech Republic. The most common hosts are B. pendula, B. pubescens, B. carpatica, and F. sylvatica. Less frequent hosts include Acer campestre, Acer pseudoplatanus, Alnus glutinosa, Alnus incana, Fraxinus excelsior, Quercus cerris, Q. petraea, Q. robur, Q. delachampii, and Ulmus sp.

• Mycobiology
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• v.44 no.4
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• pp.319-324
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• 2016

Dieback in strawberry (Seolhyang cultivar) was first observed during the nursery season (June to September) in the Nonsan area of Korea in the years 2012 and 2013. Initial disease symptoms included dieback on runners, as well as black rot on roots, followed by wilting and eventually blackened, necrotic discoloration in the crowns of daughter plants. A fungus isolated from the diseased roots, runners, and crowns is close to Lasiodiplodia theobromae based on morphological characteristics. Analysis of a combined dataset assembled from sequences of the internal transcribed spacer and translation elongation factor 1- alpha genes grouped nine fungal isolates with the type strain of L. theobromae. The isolates showed strong pathogenicity on strawberry cultivars Kumhyang, Seolhyang, and Akihimae, fulfilling Koch's postulates. Based on these results, the pathogen responsible for dieback on strawberry plants in Korea was identified as L. theobromae.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.135-145
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• 1981

Vegetables including Chinese cabbage and radish have been grown in alpine areas such as Muju, Namweon, Jinan and Jangsu during the shortage period of vegetables. The incidence of various diseases, environmental factors such as temperatures and rainfalls, and aphid populations as virus vector were observed at 10-day intervals from July to September in those areas. Disease incidence showed no significant difference among locations. Major diseases in Chin ese cabbage were bacterial soft rot, white spot, downy mildew, mosaic virus, Alternaria leaf spot and Fusarium seedling blight. Major diseases in radish were virus, white rust, black rot, root rot, leaf spot and Fusarium seedling blight. Disease incidence reached peak on Aug. 20 with $27\%$ infection in radish and with $20\%$ infection in Chinese cabbage during the growing season, and declined thereafter. Percentage of infection in each growth stage showed $25\%$ at root thickening stage and $26\%$ at the harvest time in radish; and the head formation stage, $24\%$ at the harvest time. The data indicate that disease incidence in radish increased rapidly at late growing stage and progressively increased in Chinese cabbage Seedling blight caused by Fusarium sp. and root rot caused by Aphanomyces sp. were also observed in those areas. Cool and wet weather appeared to be favorable for disease incidences during the rainy period of growing season although average temperature was about $25^{\circ}C$. Populations of aphids were lower in the alpine vegetable growing area than that of flat areas. Aphids as virus vectors from total aphids collected were $73.5\%$ or 289 virus vectors /993 total aphids in Namweon and $18.1\%$ or 31 virus vectors/171 total aphids in Muju. The most prerevalent species of aphids was Myzus persicae Sulz.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.577-582
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• 2011

Greenhouse satsuma mandarins (Citrus unshiu Marc., cv. Gungchun) of an early harvesting cultivar were treated by hot water showering at 65$^{\circ}C$ for 10 s at a commercial scale in a packing house and then stored at 5$^{\circ}C$ for 3 weeks and subsequently at 18$^{\circ}C$ for 1 week (simulated shelf-life) to examine the potential use of hot water treatment (HWT) as an environmentally benign method to maintain mandarin quality characteristics during postharvest storage and sale. The respiration rate just after heat treatment or during storage was at a similar level in both the treated and untreated fruit. HWT also had no detrimental effects on quality attributes including pH, titratable acidity, soluble solids content, weight loss, firmness, and peel color. The development of stem-end rot, mold decay, and black rot was lower in the heat-treated fruit compared to those in the untreated control. A sensory evaluation showed that HWT markedly improved fruit appearance, making the fruit cleaner and glossier. The results suggested that HWT can be applied to satsuma mandarin as an effective pretreatment to maintain postharvest quality during storage and marketing.

• Journal of Life Science
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• v.27 no.6
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• pp.688-693
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• 2017

Antifungal bacterium against Colletotrichum coccodes causing black dot disease of potatoes and anthracnose of tomatoes was isolated from sewage sludge. The isolate showed a 99% sequence homology of partial 16S rRNA of Bacillus methylotrophicus CBMB205 and Bacillus amyloliquefaciens subsp. plantarum FZB42. The isolate was identified as Bacillus sp. SW29-2, using the neighbor-joining phylogenetic tree, BlastN sequence analysis, and morphological and cultural characteristics. Bacillus sp. SW29-2 is an aerobic, Gram-positive, endospore-forming bacterium, of which the morphological and physiological characteristics were the same as those of type strain B. lichniformis CBMB205, except for the cell growth of over 4% NaCl. The cell growth of the temperature and the initial pH of the medium was shown at $18-47^{\circ}C$ (opt. ca. $38^{\circ}C$) and 3-9 (opt. ca. 6.0), respectively. The inhibition size (diameter) of Bacillus sp. SW29-2 against four strains of C. coccodes ranged from 23 to 29 mm. Also, the isolate showed antifungal activity against penicillium rot-causing Penicillium expansum in apples. Thus far, any report on the antifungal activity of Baciilus spp. against C. coccodes has not been found. These results suggest that the Bacillus sp. SW29-2 isolate could be used as a possible biocontrol agent against C. coccodes, and further applied to other plant pathogenic fungi.

• Research in Plant Disease
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• v.13 no.1
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• pp.66-70
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• 2007

During 1997 and 1998, a new disease of lettuce (Lactuca sativa) was observed on greenhouse-grown plants in Kwangju and Kwangmyung. Lesions on leaves were irregular, small, pale green to black, water-soaked, and 2 to 5 mm in diameter, Coalescing lesions sometimes caused defoliation of older leaves. Isolations made from diseased leaves on yeast extract dextrose calcium carbonate agar yielded nearly pure cultures of a yellow pigmented bacterium typical of a xanthomonad. Two bacterial strains (SL0246 and SL1352) were purified and used for further tests. Pathogenicity of strains was confirmed on 5-week-old lettuce plants injected with bacterial suspensions containing $10^8$ cfu/ml of phosphate buffered saline. The representative Xanthomonas strains isolated from lettuce were compared with a reference strain X. campestris pv, vitians for fatty acid profiles and metabolic fingerprints using GN2 microplate, showing that all outcomes were indistinguishable between the representative and reference strains. This is the first report of bacterial leaf spot and dry rot of lettuce in Korea.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.135-141
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• 2006

We isolated a bacterium which produces antifungal substances from the Sanktpeterburg soils at Russia. The iso-lated strain was identified as Brevibacillus sp. and shown a strong antifungal activity on plant pathogenic fungi. Brevibacillus sp. KMU-391 produced maximum level of antifungal substances under incubation aerobically at $30^{\circ}C$ for 48 hours in trypticase soybean broth containing 1.0% sucrose and 1.0% polypeptone at 180 rpm and initiated pH adjusted to 7.0. Precipitate of culture broth by $30{\sim}60%$ ammonium sulfate precipitation exhibited strong antifungal activity against Didymella bryoniae by dry cell weight. Butanol extract of cultured broth also shown fungal growth inhibitory activity against Botrytis cinerea KACC 40573, Botrytis fabae KACC 40962, Colletotrichum gloeosporioides KACC 40804, Colletotrichum orbiculare KACC 40808, Didymella bryoniae KACC 40669, Fusarium graminearum KACC 41040, Fusarium oxysporum KACC 40037, Fusarium oxysporum KACC 40052, Fusarium oxysporum f, sp. radicis-Iycopersici KACC 40537, Fusarium oxysporum KACC 40902, Monosporascus cannonballus KACC 40940, Phytophthora camvibora KACC 40160, Rhizoctonia solani AG-1(IA) KACC 40101, Rhizoctonia solani AG-4 KACC 40142, and Scleotinia scleotiorum KACC 41065 by agar diffusion method.

• 보존과학연구
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• s.35
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• pp.121-127
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• 2014

The Vietnam homecoming box that has been collected in National Museum of Korean The Vietnam homecoming box that has been collected in National Museum of Korean Contemporary History got severely damaged such as rot, attached foreign substance, fading, color, wood decay. In particular, the bottom of the box was unstable state that deteriorated by pests and the left strut was severely damaged by some deep cracks and pests. The metal bands were remained on the side and bottom of the box, and all the bands were seriously corroded. On the bottom-right of the lid, black foreign matter was adhered to the surface. In the process of conservation treatments, the cleaning, filling cracks, reinforcing the bottom of the box, attaching the metal bands were proceed in order after the investigation of the state.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.226-231
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• 2006

Several white-rot fungi are able to produce extracellular lignin-degrading enzymes such as manganese peroxidase (MnP), lignin peroxidase (LiP), and laccase. In order to enhance the production of laccase and MnP using Trametes versicolor KCTC 16781 in suspension culture, the effects of major medium ingredients, such as carbon and nitrogen sources, on the production of the enzymes were investigated. The decolorization mechanism in terms of biodegradation and biosorption was also investigated. Among the carbon sources used, glucose showed the highest potential for the production of laccase and MnP. Ammonium tartrate was a good nitrogen source for the enzyme production. No significant difference in the laccase production was observed, when glucose concentration was varied between 5 g/l and 30 g/l. As the concentration of nitrogen source increased, a lower MnP activity was observed. The optimal C/N ratio was 25 for the production of laccase and MnP. When the concentrations of glucose and ammonium tartrate were simultaneously increased, the laccase and MnP activities increased dramatically. The maximum laccase and MnP activities were 33.7 U/ml at 72 h and 475 U/ml at 96 h, respectively, in the optimal condition. In this condition, over 90% decolorization efficiency was observed.

• Research in Plant Disease
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• v.17 no.1
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• pp.95-98
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• 2011

This research was carried out to selection of desirable cultivar for organic cultivation of carrot in Korea. The assay of disease resistance, insect tolerance and rate of bolting were investigated on 32 cultivars of genetic resources of carrot. This experiment was carried out at experimental field and greenhouse of Gangneung-Wonju National University. 'PI 223360' was resistant against powdery mildew. Ten cultivars including 'Oxheart Carrot Heirloom' were moderately resistant, 22 cultivars including 'Long Impeator #58' were susceptible to powdery mildew. Although there was no resistant cultivar against black rot and leaf blight, our results showed that several cultivars have moderate resistance. Thirteen cultivars including 'Oxheart Carrot Heirloom' were having insect (Erythroplusia pyropia) tolerance and 'SA 102' and 'Scarlet Keeper Carrot Rare' were susceptible. According to the investigation of bolting, 6 cultivars including 'Hongsim Ouchon Carrot' were early bolting and 4 cultivars including 'Japanese Imperial Long Carrot' were moderate bolting. Other cultivars were identified as late bolting. From above results, we confirmed that 'Oxheart Carrot Heirloom' was suitable cultivar for organic cultivation among 32 genetic resources of carrot.