• Mycobiology
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• v.45 no.1
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• pp.39-43
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• 2017

Leaf spot disease on black chokeberry (Aronia melanocarpa) was observed at several locations in Korea during 2014-2015. Leaf spots were distinct, scattered over the leaf surface and along the leaf border, subcircular to irregular and brown surrounded by a distinct dark color, and were expanded and coalesced into irregularly shaped lesions. Severely infected leaves became dry and fell off eventually. The causative agent was identified as Pseudocercospora pyricola. Morphological observations and phylogenetic analyses of multiple genes, including internal transcribed spacer, translation elongation factor 1-alpha, actin, and the large subunit ribosomal DNA were conducted. The pathogenicity test was conducted twice yielding similar results, fulfilling Koch's postulates. To our knowledge, this is the first report on P. pyricola infection of A. melanocarpa globally.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1858-1861
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• 2005

Automatic nut sorting machine used to calculate the size of inserted nut and detect the black spot defection is introduced in this paper. Because most of farm products are imported from the underdeveloped countries, domestic farm products have no place to be sold in market. To overcome this critical situation, lowering the productivity cost is strongly demanded to compete with foreign corps. Imaged processed nut sorting algorithm is developed to the automatic nut sorting machine to remove the sorting time which takes lots of man power. This system is composed of mainly two parts, mechanical parts and vision system. The purpose of mechanical part is supplying the nuts automatically to make computer system capture the images of objects. Simplified mechanical system was assembled followed by 3D simulation by Pro/E design for the adaptive cost effects. Several image processing algorithms are designed to detect the spot defects and calculate the size of nuts. Test algorithm shows good results to the designed automatic nut sorting system.

• The Plant Pathology Journal
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• v.22 no.4
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• pp.375-380
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• 2006

In the survey from 1992 to 2000, twenty-eight parasitic diseases were observed in major apple producing areas in Korea. The predominant apple diseases were white rot(Botryosphaeria dothidea), Marssonina blotch(Marssonina mali), Valsa canker(Valsa ceratosperma), Alternaria leaf spot(Alternaria mali), and bitter rot(Collectotrichum gloeosporioides and C. acutatum). Apple scab that reappeared in 1990 after disappearance for 15 years was disappeared again since 1997. A viroid disease(caused by apple scar skin viroid) was newly found in this survey. The five diseases, fire blight(Erwinia amylovora), black rot(Botryosphaeria obtusa), scab(Cladosporium carpophilum), Monochaetia twig blight(Monochaetia sp.), and brown leaf spot(Hendersonia mali), which had once described in 1928 but no further reports on their occurrence, were not found in this survey. However, blossom blight(Monilinia mali), brown rot(Monilinia fructigena), and pink rot(Trichothecium roseum), which did not occur on apple after mid 1970s, were found in this survey.

• Research in Plant Disease
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• v.8 no.2
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.374-381
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• 2021

A newly recorded chaetodontid species, Chaetodon speculum Cuvier, 1831 was collected in July, 2021 from Pohang, Korea. Its body color is yellow with black stripe across the eyes and a large spot occupying one fourth of the upper part of the body. C. speculum is very similar to congeneric species, C. zanzibarensis, but it can be distinguished by the size of the spot, shape of the lateral line, number of longitudinal line scales and geographic distribution. C. speculum is readily identified between post-larval stage and adult stage because of its similar external shape. Molecular analysis based on mitochondrial DNA COI sequences showed our specimen perfectly matched C. speculum. Therefore, we propose the new Korean name, "Heug-jeom-na-bi-go-gi" for C. speculum.

• Journal of Mushroom
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• v.21 no.4
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• pp.195-199
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• 2023

The fungus Alternaria alternata, responsible for causing brown to black spotting on numerous fruits and vegetables globally, was identified in 2022 as the causative pathogen of brown spot disease in potatoes in Korea. In pursuing potential inhibitors against A. alternata growth, we evaluated 15 mushroom culture filtrates: eight from Trametes spp. and seven from Polyporus spp., known for their antibacterial and anticancer properties. Antifungal activity was assessed by exposing each filtrate to A. alternata on a paper disc. Four filtrates displayed inhibitory action against the fungus, albeit with mild effects. Our findings highlight the potential of Trametes and Polyporus fungi as emerging antifungal candidates, offering promise in preventing potato brown spots.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.207-222
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• 2018

In this study, light absorption of carbonaceous species in $PM_{2.5}$ was investigated using a dual-spot 7-wavelength Aethalometer(model AE33) with 1-min time interval between January 01 and September 30, 2017 at an urban site of Gwangju. During the study period, two Asian dust (AD) events occurred in April (AD I) and May (AD II), respectively, during which light absorption in total suspended particles was observed. Black carbon (BC) was the dominant light absorbing aerosol component at all wavelengths over the study period. Light absorption coefficients by aerosol particles were found to have 2.7~3.3 times higher at 370 nm than at 880 nm. This would be attributed to light absorbing organic aerosols, which is called brown carbon (BrC), as well as BC as absorbing agents of aerosol particles. Monthly average absorption ${{\AA}}ngstr{\ddot{o}}m$ exponent ($AAE_{370-950nm}$) calculated over wavelength range of 370~950 nm ranged from 1.10 to 1.35, which was lower than the $AAE_{370-520nm}$ values ranging from 1.19~1.68 that was enhanced due to the presence of BrC. The estimated $AAE_{370-660nm}$ of BrC ranged from 2.2 to 7.5 with an average of 4.22, which was fairly consistent to the values reported by previous studies. The BrC absorption at 370 nm contributed 10.4~28.4% to the total aerosol absorption, with higher contribution in winter and spring and lower in summer. Average $PM_{10}$ and $PM_{2.5}$ concentrations were $108{\pm}36$ and $24{\pm}14{\mu}g/m^3$ during AD I, respectively, and $164{\pm}66$ and $43{\pm}26{\mu}g/m^3$ during AD II, respectively, implying the greater contribution of local pollution and/or regional pollution to $PM_{2.5}$ during the AD II. BC concentration and aerosol light absorption at 370 nm were relatively high in AD II, compared to those in AD I. Strong spectral dependence of aerosol light absorption was clearly found during the two AD events. $AAE_{370-660nm}$ of both light absorbing organic aerosols and dust particles during the AD I and II was $4.8{\pm}0.5$ and $6.2{\pm}0.7$, respectively. Higher AAE value during the AD II could be attributed to mixed enhanced urban pollution and dust aerosols. Absorption contribution by the light absorbing organic and dust aerosols estimated at 370 nm to the total light absorption was approximately 19% before and after the AD events, but it increased to 32.9~35.0% during the AD events. In conclusion, results from this study support enhancement of the aerosol light absorption due to Asian dust particles observed at the site.

• Journal of Korean Society of Transportation
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• v.35 no.2
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• pp.129-142
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• 2017

Accident Black Spot Improvement Project is the representative road safety intervention to eliminate environmental risk factors on the roadway by installing road safety facilities. Although it is one of the main road safety projects in Korea, there has been a lack of effort analyzing the traffic accident reduction effects of this project. In this study, therefore, we selected 4,171 road black spots from 2004 to 2013 and investigated the traffic accident reduction effects of 5 road safety facilities by using "Comparison Group(C-G)" method. Through the analysis, it was found that the number of traffic accidents were lowered by 4.45% with traffic islands, 32.17% with road paved markers, and 24.13% with speed cameras, respectively. However, 0.61% with pedestrian fencing and 1.67% with skid resistant pavement were increased on the other hand. In addition, we also analyzed traffic accident reduction facilities' performance on specific types of collision mentioned in manual on road safety facilities by Ministry of Land, Infrastructure and Transport. It was shown that the number of bad weather traffic accidents were reduced by 52.96% with road paved markers, pedestrians accidents were reduced by 62.77% with pedestrian fencing and rear-end collisions were reduced by 26.00% with skid resistant pavement.

• Korean Journal of Ichthyology
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• v.27 no.3
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• pp.249-252
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• 2015

This is the first report of Chaetodontoplus melanosoma, belonging to the family Pomacanthidae, collected in Korea. The specimen (123.1 mm in standard length) was caught in the coastal waters of Jejudo Island by a trammel net on 23 February 2010. This species was characterized by the following morphological traits: 26 dorsal fin rays, 16 pectoral fin rays, 6 pelvic fin, 21 anal fin rays, no blue strips on the body, no markings behind the eye, and an egg-shaped faint black spot on the base of the pectoral fin. We suggest a new Korean name "Geom-eun-cheong-jul-dom" for C. melanosoma.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.381-384
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• 2014

A single specimen belonging to the family Diodontidae was collected from Seo-gwi-po, Jeju Island, Korea in July 2013 and was identified as Diodon hystrix Linnaeus, 1758, a species new to the Korean fish fauna. The species is characterized by 14 dorsal fin rays, 14 anal fin rays, spines on the dorsal and ventral surfaces of the caudal peduncle, and many small black spots on all fins except the anal fin. The most similar species, Diodon holocanthus, is well distinguished from D. hystrix by the absence of black spots on the dorsal and caudal fins, and the lack of a spine on the dorsal surface of the caudal peduncle. Accordingly, we describe herein the morphological traits of D. hystrix and suggest its new Korean name, "Jan-jeom-bak-i-ga-si-bok".