• Journal of Ginseng Research
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• v.42 no.3
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• pp.304-311
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• 2018

Background: Ginseng black spot disease resulting from Alternaria panax Whuetz is a common soil-borne disease, with an annual incidence rate higher than 20-30%. In this study, the bacterial strains with good antagonistic effect against A. panax are screened. Methods: A total of 285 bacterial strains isolated from ginseng rhizosphere soils were screened using the Kirby-Bauer disk diffusion method and the Oxford cup plate assay. We analyzed the antifungal spectrum of SZ-22 by confronting incubation. To evaluate the efficacy of biocontrol against ginseng black spot and for growth promotion by SZ-22, we performed pot experiments in a plastic greenhouse. Taxonomic position of SZ-22 was identified using morphology, physiological, and biochemical characteristics, 16S ribosomal DNA, and gyrB sequences. Results: SZ-22 (which was identified as Brevundimonas terrae) showed the strongest inhibition rate against A. panax, which showed 83.70% inhibition, and it also provided broad-spectrum antifungal effects. The inhibition efficacies of the SZ-22 bacterial suspension against ginseng black spot reached 82.47% inhibition, which is significantly higher than that of the 25% suspension concentrate azoxystrobin fungicide treatment (p < 0.05). Moreover, the SZ-22 bacterial suspension also caused ginseng plant growth promotion as well as root enhancement. Conclusion: Although the results of the outdoor pot-culture method were influenced by the pathogen inoculum density, the cropping history of the field site, and the weather conditions, B. terrae SZ-22 controlled ginseng black spot and promoted ginseng growth successfully. This study provides resource for the biocontrol of ginseng black spot.

• Research in Plant Disease
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• v.10 no.3
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• pp.183-187
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• 2004

Black spot disease on sweet persimmon (Diospyros kaki cv. Fuyu) was found from the farmer's refregerated ware house located in Dong-eup, Changwon city, Gyeongnam province, Korea, 2002. The typical symptoms of the disease was appeared black spot on surface of fruits. Colonies of causal fungus were developed velvety and later turned olivaceous black to sooty black in color on PDA. Conidia were pale brown to golden brown in color and ovoid, obclavate to obpyriform, rarely ellipsoid in shape. and were 12∼46 ${\times}$ 6∼12 ${\mu}{\textrm}{m}$ in size. Septa were 3∼5 transvers, 1∼2 longitudinal or oblique. Conidia were mostly beakless and generated chains by means of secondary conidiophores. Conidiophores were pale to mid brown in color and 42∼95 ${\times}$ 3∼5 ${\mu}{\textrm}{m}$ in size. The optimum temperature for growth of the fungus was about 25∼3$0^{\circ}C$. This is the first report on the black spot of sweet persimmon caused by Alternaria alternata (Fr.) Keissler in Korea.

• Mycobiology
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• v.44 no.3
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• pp.187-190
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• 2016

In July 2015, diseased leaves of black chokeberry (Aronia melanocarpa) were observed in Danyang and Gochang, Korea. The symptoms appeared as circular or irregular brown leaf spots, from which Alternaria tenuissima was isolated. The isolates were cultured on potato dextrose agar, and their morphological characteristics were observed under a light microscope. The colonies were whitish to ash colored. The pathogenicity test on healthy black chokeberry leaves produced circular brown spots, in line with the original symptoms. Molecular analyses of the ITS, GPD, RPB2, and TEF genes were conducted to confirm the identity of the pathogen. The phylogeny of the multi-gene sequences indicated that the causal agent was A. tenuissima. This study is the first report of A. tenuissima leaf spot on black chokeberry (A. melanocarpa).

• Research in Plant Disease
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• v.9 no.3
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• pp.149-152
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• 2003

Black leaf spot disease occurred on Dendrobium phalaenopsis grown in farmer's fields located in Bonggangmyon, Gwangyang-eup, Jeonnam, Korea. Black small spots occurred on leaves at initial stage of infection and the infected leaves turned yellow from the tip. The yellow leaves were falled, resulting in stem blighting or eventual death of the entire plant. White mycelial colony of the causal fungus grown on potato dextrose agarturned dark violet later and optimum temperature for the mycelial growth was $25^{\circ}C$. The causal fungus isolated from the black leaf spot on D. phalaenopsis was identified as Fusarium moniliforme based on the mycological characteristics and pathogenicity. The fungus also caused same symptoms on leaves of Phalaenopsis sp. and Cymbidium sp. as well sa D. phalaenopsis by wound inoculation. This is the first report on black leaf spot of D. phalaenopsis caused by F.moniliforme in Korea.

• Mycobiology
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• v.41 no.3
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• pp.167-169
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• 2013

Black spot of sweet persimmon, caused by Alternaria alternata, occurred in an orchard in Gyeongnam province, Korea in 2012. The symptom was appearance of 0.5 to 4 cm black spots on the surface of fruit. The pathogen was isolated from flesh of disease lesions. The causal agent was identified as A. alternata by morphological characteristics and sequencers of the internal transcribed spacer (ITS) 1 and ITS4 regions of rRNA. Artificial inoculation of the pathogen resulted in development of disease symptoms and the re-isolated pathogen showed characteristics of A. alternata.

• The Journal of Fisheries Business Administration
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• v.37 no.1 s.70
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• pp.95-110
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• 2006

Japan's frozen shrimp future market is the only fisheries future commodity market in the world. This empirical study examines the lead and lag relationship between Japan frozen shrimp spot and future markets using the daily prices from August 1, 2002 to December 31, 2005. Frozen shrimp future contract is listed on Japan Kansai Commodities Exchange. Japan imports approximately 250,000 tons of frozen shrimp annually, of which just under 70,000 tons, nearly 30%, are black tiger shrimp. Approximately 90% of black tiger shrimp are caught in Indonesia, India, Thailand and Vietnam, and the two largest consumers of these shrimp are Japan and the U.S.A. Kansai Commodities Exchange adopts the India black tiger shrimp as standard future commodity. We use unit root test, Johansen cointegration test, Granger causality test, Vector autoregressive analysis and Impulse response analysis. However, considering the long - term relationships between the level variables of frozen shrimp spot and futures, we introduced Vector Error Correction Model. We find that the price change of frozen shrimp futures with next 1, 2, 3, 4, 5 month maturity have a strong predictive power to the change of frozen shrimp spot and the change of frozen shrimp spot also have a predictive power to the change of frozen shrimp with next 1, 2, 3 month maturity. But, the explanatory power of the frozen shrimp futures is relatively greater than that of frozen shrimp spot.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.67-74
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• 2008

Even though the efficiency of a point based black spot improvement project has been low, none of solid methodology, which is based on section not point, and is considered as one of the promising substitute, has not been come up with yet. Thus, this research aims at proposing the adequate length of a hazardous section and a method to set segment length over which the project needs to be performed on rural highways by analyzing the distances from project-conducted sites to new black spots in the following year and distances between project needed but not conducted sites and new black spots in the following year. According to the analysis, the probability of being a new black spot near the project conducted intersection is higher than that of a non-conducted intersection within 2km, however, no strong relationships between project types and distance distribution have been found. Based on those findings, a method to determine the target segment including adjacent black spots within 2 kilometers-range was proposed.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.7
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• pp.1047-1053
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• 2013

Five hundred and forty crossbred (Korean native black pig${\times}$Landrace) F2 were selected at a commercial pig farm and then divided into six different coat color groups: (A: Black, B: White, C: Red, D: White spot in black, E: Black spot in white, F: Black spot in red). Birth weight, 21st d weight, 140th d weight and carcass weight varied among the different coat color groups. D group (white spot in black coat) showed a significantly higher body weight at each weigh (birth weight, 140th d weight and carcass weight) than did the other groups, whereas the C group (red coat color) showed a significantly lower body weight at finishing stage (140th d weight and carcass weight) compared to other groups. Meat quality characteristics, shear force, cooking loss and meat color were not significantly different among the different coat color groups, whereas drip loss was significantly higher in F than in other groups. Most blood characteristics were not significantly different among the different groups, except for the red blood cells.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.7-14
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• 1984

Recently, a symptom similiar to black spot caused by Alternaria kikuchiana on the pear leaves is prevailing in Naju, Chonnam Province. This experiment was conducted in order to clarify causal agent and to survey present status on it. Disease lesions on the leaves were brown or black brown in color, circle or irregular circle in shape, $2\~6mm$ in diameter, and faintly zonal. Central part of lesions was gradually changed to greyish-white. The causal fungus was identified as Alternaria kikuchiana Tanaka causing black spot of pear reported previously on variety I-sib-se-gi (Nijisseki) of pear. However, this disease differed from that of typical black spot reported already in some aspects; It occurred more highly on matured leaves than on young ones. And it occurred severely in varieties Shin-heung, Shin-ko, Man-sam-gil(Okusankichi) etc. which have been reported as resistant varieties, while slightly in varieties Cho-ok(Hayadama), Park-da-cheung (Hakadahare) etc. which have been known as susceptible ones. From the results described above, it is considered that this disease is due to the differentiation in pathogenicity of Alternaria kikuchiana Tanaka in that area.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.434-439
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• 2017

Incidence rates of diseases in kiwiberry orchards were investigated monthly from late June to late September in Gwangyang and Boseong in 2015 and 2016. The impact of postharvest fruit rot was investigated during ripening after harvest. Bacterial canker was only observed on one single tree in 2015, but black rot, powdery mildew, leaf spot and blight, and postharvest fruit rot diseases were problematic throughout the study period in both 2015 and 2016. Incidence rates of the diseases varied with kiwiberry cultivar, region and sampling time. Incidence rates of powdery mildew, leaf spot and blight diseases increased significantly during the late growing stages near fruit harvest, while black rot peaked in late August. Incidence rate of postharvest fruit rot on fruit without fruit stalks was less than half of fruit with fruit stalks, regardless of kiwiberry cultivars. Among the four cultivars, Mansu was relatively resistant to black rot and postharvest fruit rot diseases. In our knowledge, this is the first report of various potential pathogens of kiwiberry in Korea.