• Title/Summary/Keyword: brown spots

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Gray Mold Rot of Eggplant Caused by Botrytis cineraea in Greenhouse (시설재배에서 Botrytis cinerea에 의한 가지 잿빛곰팡이병)

  • 김철승;이재필;송주희;임은경;정순재;하상영;문병주
    • Journal of Life Science
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    • v.11 no.3
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    • pp.242-247
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    • 2001
  • Botrytis cinerea E12 was isolated from the leaves, flowers and fruits of eggplant in the greenhouse in Halrim, Kimhae and Dejeo, Pusan. The leaves infected with the pathogen were appeared initially brown-color, small gray spots at the edge, and finally fall down. The fruit was showed the symptoms of circular or irregular shapes, followed by sunken. When the symptoms were developed, the conidia formed on the surface with gray color. To determine the pathogenicity of B. cinerea E12 against the eggplants, the conidia were suspended with 30% tomato juice, PDB and sterile water, respectively. The result showed that the conidial suspension with 30% tomato juice was highly effective on the pathogenicity as more than 90%. Moreover, the symptoms caused by inoculum were the same as those of wild-type pathogen.

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Stem Rot of Garlic (Allium sativum) Caused by Sclerotium rolfsii

  • Kwon, Jin-Hyeuk
    • Mycobiology
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    • v.38 no.2
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    • pp.156-158
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    • 2010
  • Stem rot disease was found in garlic (Allium sativum L.) cultivated from 2008 to 2010 in the vegetable gardens of some farmers in Geumsan-myon, Jinju City, Gyeongnam province in Korea. The initial symptoms of the disease were typical water-soaked spots, which progressed to rotting, wilting, blighting, and eventually death. White mycelial mats had spread over the lesions near the soil line, and sclerotia had formed over the mycelial mats on the stem. The sclerotia were globoid in shape, 1~3 mm in size, and tan to brown in color. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) medium was $30^{\circ}C$. The diameter of the hyphae ranged from approximately 4 to $8\;{\mu}m$. Typical clamp connection structures were observed in the hyphae of the fungus, which was grown on PDA medium for 4 days. On the basis of the mycological characteristics and pathogenicity of the fungus on the host plants, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot disease in garlic caused by S. rolfsii in Korea.

A new record of the subgenus Eusimulium Roubaud from Korea with an updated key to genera and subgenera of Korean black flies(Diptera: Simuliidae)

  • Kim, Sam-Kyu
    • Journal of Species Research
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    • v.9 no.2
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    • pp.174-179
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    • 2020
  • Larvae and pupae of Simulium (Eusimulium) satsumense were collected and recorded from Korea for the first time. Detailed descriptions and photographs of both immatures are provided. Currently, 42 species are known from the subgenus Eusimulium, which is found globally, mainly in the Holarctic Region, but unknown from Korea. Members of the subgenus Eusimulium are morphologically homogeneous in male, female, and pupa, making them extremely difficult to distinguish from one another. S. (E.) satsumense can be distinguished from other Korean black flies by the following combination of the characteristics: Pupa: Gill of four slender filaments, dorsalmost filament strongly divergent from other filaments; cocoon slipper shaped without anterodorsal projection; Larva: Head spots distinctly positive; postgenal cleft short, apically rounded or squared; antenna with proximal segment brown; abdominal segments IX with prominent ventral tubercles; and rectal papillae of three simple lobes. In addition to descriptions for larvae and pupae of the species, a key to genera and subgenera of Simulium of Korean black flies are also provided.

A Case of Progressive Pigmented Purpuric Dermatosis (진행성 색소성 자반병 한방 치험 1례)

  • Choi, In-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.14 no.2
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    • pp.194-197
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    • 2001
  • Progressive pigmented purpuric dermatosis(Schamberg's disease, purpura simplex) is an uncommon eruption characterized by petechiae and patches of brownish pigmentation, particularly on the lower extremities. Lesions remain for months or years and present only a cosmetic problem. there is no hematologic disease, venous insufficiency, or associated internal disease. The most characteristic feature is orange brown, pinhead-sized "cayenne pepper" spots. It is hard to find similar disease in Oriental Medicine, however it could be though related with 瘀血. We observed and treated a 25 old female with progressive pigmented purpuric dermatosis on her lower extremities, without pain and itching sign. About 1 year after our treatment, herb-medication. acupuncture treatment, negative therapy and applied aroma oil in order to remove the 瘀血(a kind of congestion) & inner heat and promote the circulation of her blood, the area of pigmented purpuric dermatosis was decreased remarkably and the colour was lighter. She is been treated continuously now and satisfied with the efficacy of treatment.

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Morphological and Molecular Characterization of Pseudocercospora chionanthi-retusi Causing Leaf Spot on Chionanthus retusus in Korea

  • Choi, In-Young;Abasova, Lamiya;Choi, Joon-Ho;Shin, Hyeon-Dong
    • Research in Plant Disease
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    • v.28 no.2
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    • pp.57-60
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    • 2022
  • Leaves of Chionanthus retusus were found to be damaged by leaf spot disease associated with a fungus in Iksan, Korea. Leaf spots were angular to irregular, vein-limited, scattered, 1-8 mm diameter, brownish-gray to dark brown when dry, with heavy fructification. The pathogen causes premature defoliation of C. retusus plant and was identified as Pseudocercospora chionanthi-retusi based on morphological and molecular-phylogenetic analyses. The phylogenetic tree was constructed using multi-locus DNA sequence data of partial actin (actA), partial translation elongation factor 1-alfa (tef1), partial DNA-directed RNA polymerase II second largest subunit (rpb2) genes, and internal transcribed spacer regions. Current study provides detail morphological description of P. chionanthi-retusi on C. retusus in Korea, with supports of phylogenetic analysis and pathogenicity test.

Identification and Characterization of Pseudocercospora cornicola Causing Leaf Spots on Cornus officinalis

  • In-Young Choi;Ho-Jong Ju;Lamiya Abasova;Joon-Ho Choi;Hyeon-Dong Shin
    • The Korean Journal of Mycology
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    • v.50 no.2
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    • pp.131-136
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    • 2022
  • Cornus officinalis plants that grow in several locations in Korea have been found to be infected with leaf spot disease. Symptoms include necrotic lesions, which are angular, irregularly shaped, vein-limited, and dark brown, on both sides of the leaves. The causal agent of the disease was identified to be Pseudocercospora cornicola based on the morphological characteristics of the fungus and molecular phylogenetic analysis of the obtained multi-locus DNA sequence data. This is the first report investigating P. cornicola found on C. officinalis in Korea.

Incidence of Beet Leaf Spot Caused by Neocamarosporium betae in Korea

  • Gyo-Bin Lee;Hong-sik Shim;Weon-Dae Cho;Wan-Gyu Kim
    • The Korean Journal of Mycology
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    • v.51 no.1
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    • pp.63-68
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    • 2023
  • From June to August 2021, we surveyed diseases affecting beet (Beta vulgaris subsp. vulgaris) plants in Cheolwon, Hoengseong, and Pyeongchang regions in Gangwon Province, Korea. We observed severe leaf spot symptoms, such as brown to dark circular or irregular spots on the leaves, in plants. Disease incidence in the plant leaves in the fields investigated at the three locations ranged from 1 to 80%. Five single-spore isolates of Phoma sp. were obtained from the diseased leaves and identified as Neocamarosporium betae based on their cultural, morphological, and molecular characteristics. Three isolates of N. betae were subsequently tested to confirm their pathogenicity in beet plants via artificial inoculation. The tested isolates caused leaf spot symptoms in the inoculated plants, similar to those observed in the plants in the investigated fields. Therefore, our findings revealed N. betae as the pathogen causing beet leaf spot in Korea.

Alternaria solani Causing Leaf Blight Disease on Aster glehni in Korea

  • Jeon, Chang Wook;Hong, Sung Woon;Cho, Hyunji;Kwak, Youn-sig
    • Journal of agriculture & life science
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    • v.50 no.4
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    • pp.249-253
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    • 2016
  • Aster glehni Franchet et Schmidt is a compositae plant and has been known as a native specie in Ulleung Island, Korea. It is officially recognized as a regional specialty that grows only in this region. In 2014, brown and dark spots were observed on aster leaves in a forest research field, Jinju, Korea. A causal agent was isolated from the disease symptomatic leaves and identified as fungus Alternaria solani. Fungal morphological characteristics and molecular identification with internal transcribed spacer sequences were synchronized as A. solani. The isolated fungi reproduced the same disease symptoms when the fungus was artificially inoculated on healthy aster leaves. This is the first report that A. solani caused leaf blight disease in Aster glehni in Korea.

Occurrence of Brown Rot on Apricot Caused by Monilinia fructicola in Korea (Monilinia fructicola 에 의한 살구 잿빛무늬병)

  • Choi, In-Young;Kim, Ju;Seo, Kyoung-Won;Oh, Hun-Tak;Cho, Chong-Hyeon;Kim, Jin-Ho;Song, Young-Ju
    • Research in Plant Disease
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    • v.22 no.2
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    • pp.122-126
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    • 2016
  • In June 2015, an exhibited typical signs and symptoms of brown rot was observed on fruit of Apricot cvs. Modern and Alexander at an incidence of 5% of fruit in Jeonju, Korea. Early symptoms on fruit showed small, circular, light brown spots that eventually destroyed the entire fruit. Small sporodochia appeared on the fruit surface. Fruit susceptibility to brown rot increases during the 1 to 2 weeks period prior to harvest. The conidia were one-celled, hyaline, lemon-shaped, $14.6-18.0{\times}8.5-11{\mu}m$, and borne in branched monilioid chains. Based on the morphological characteristics and phylogenetic analysis of internal transcribed spacer (ITS), the fungus was identified as Monilinia fructicola. A BLAST search revealed that sequences of the fungus shared 100% identity to those of M. fructicola. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first confirmed report on the occurrence of M. fructicola on apricot in Korea.

Characteristics of Brown Rot Caused by Monilinia fructicola on Stone Fruit in Korea (핵과류 잿빛무늬병을 일으키는 Monilinia fructicola 병해 특성)

  • Oh, Hun-Tak;Choi, In-Young;Kim, Ju;Na, Young-Eun;Lee, Wang-Hyu;Lee, Kui-Jae;Shin, Hyeon-Dong
    • Research in Plant Disease
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    • v.23 no.4
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    • pp.322-333
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    • 2017
  • In June and July 2015 and 2017, typical signs and symptoms of brown rot were observed on the fruit of Japanese apricot, peach, apricot, Japanese plum, and sweet cherry with incidence levels of 2-5% in Jeonju and Imsil, Korea. Early symptoms were small, circular, light brown spots that eventually destroyed entire fruit. Small sporodochia later appeared on the surface. Conidia isolated from each host were one-celled, hyaline, lemon-shaped and borne in branched monilioid chains. The optimal temperature range for hyphal growth of all the isolates was $20-25^{\circ}C$. The growth of hyphae was faster on potato dextrose agar and oatmeal agar than others. Multiple alignments using the ITS sequences from different host showed that they matched each other (100%). The ITS sequences showed 100% identity to those of M. fructicola. Based on the morphological characteristics and phylogenetic analysis via internal transcribed spacer (ITS), all the isolate was identified as M. fructicola. Pathogenicity of representative isolates was proved by artificial inoculation, fulfilling Koch's postulates. This is the first confirmed report on brown rot caused by M. fructicola on stone fruit in Korea.