• Title/Summary/Keyword: Dark spots

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Rust of Korean Azalea (Rododendron yedoense) Caused by Chrysomyxa rhododendri (Chrysomyxa rhododendri에 의한 산철쭉(Rododendron yedoense) 녹병)

  • Do, Yun-Jeong;Kim, Hyung-Moo;Lee, Kui-Jae;Lee, Wang-Hyu;Ko, Jeong-Ae
    • Research in Plant Disease
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    • v.13 no.3
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    • pp.220-222
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    • 2007
  • Rust disease on Korean Azalea (Rododendron yedoense) was occurred in Jeonju, Jeonbuk province of Korea. The typical symtoms of the disease appeared first as small yellowish spots on leaves. Uredinia were observed at hypophyllous of the leaves, yellow or dark yellow in color and globoid in shape with the size of $0.27{\sim}0.46{\times}0.31{\sim}0.61$ mm. Urediniospores were also observed in the leaves, yellow in color with globoid or ovoid in shape with the size of $17.1{\sim}29.2{\times}12.8{\sim}18.2{\mu}m$. Surface characterization of the spores revealed that these spores have papilla-like projections, which were made of $2{\sim}3$ annulation (SA; small annulate). Based on these morphological characterizations the causative fungus was identified as Chrysomyxa rhododendri.

First Record of a Filefish, Thamnaconus tessellatus (Monacanthidae: Tetraodontiformes) from Jeju Island, Korea (한국산 쥐치과 미기록종, Thamnaconus tessellatus의 최초 보고)

  • Park, Jeong-Ho;Jang, Seo Ha;Kim, Do Gyun;Jeong, Jae-Mook;Kang, Sukyung;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • v.29 no.4
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    • pp.277-281
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    • 2017
  • A single specimen (273.1 mm in standard length) of the monacanthid Thamnaconus tessellatus was caught by one-boat trawl from western Jeju Island and then collected at Busan Cooperative Fish Market (BCFM) on 30 May 2015. The specimen is characterized by both head and body with many dark brown spots densely, posterior margin of caudal fin no black, first dorsal spine originates the posterior half of eye, and 34~37 dorsal fin rays. This is the first record of T. tessellatus in Korea; we therefore add the species to the Korean fish fauna. According to the Yamada et al. (1995), we propose the Korean name, "Nam-byeol-jwi-chi" for this species.

The Occurrence of Strawberry Black Leaf Spot Caused by Alternaria alternate (Fr.) Keissler in Korea (딸기 검은무늬병(Alternaria alternata (Fr.) Keissler)의 발생에 관하여)

  • Cho J.T.;Moon B.J.
    • Korean journal of applied entomology
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    • v.19 no.4 s.45
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    • pp.221-227
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    • 1980
  • A new disease of strawberry caused by Alternaria was found in Gim Hae, Gyougnam province, in July 1979. The symptoms of the disease occurred mainly on leaves as showing dark brown spots with circular to irregular, $5\~6mm$ in diameter. The pathogen was identified as Alternaria alternate (Fr.) Keissler which has not been described in Korea as a pathogen of strawberry disease. The common name of the disease was given as Gum un mum byung of strawberry. The conidia shape and size of this fungus varied considerably with culture media. The measurements of conidia and beak on corn meal agar were $20.1\times9.3{\mu}\;and\;4.0\mu$, respectively, which were shorter than those on strawberry leaf lesions in the field. Among 49 strawberry varieties tested, Morioca 16 and Robinson were highly susceptible to the disease by artificial inoculation and Catskill, Cyclone, Northwest, Merton princess, Juspa and Daehak I were moderately susceptible whereas 31 varieties were resistant. This fungus could also infect the leaf of Common garden sunflower, Double sunflower and Mexican sunflower among the 14 plants species tested.

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Curing period affect the occurrence of black dot, weight loss and sprouting of potato tubers during storage

  • Chang, Dong Chil;Jin, Yong Ik;Jee, Sam Nyu;Nam, Jung Hwan;Yoo, Dong Lim;Cheon, Chung Gi;Choi, Jong Keun;Kim, Su Jeong;Yu, Hong-Seob
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.242-242
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    • 2017
  • A potato cultivar, Haryeong, was released for table stock in 2005 and has been supplied to farmers since 2010. Black dot has been known as a disease causing tuber blemishes in the cultivar, which is primarily an issue in storage. To investigate the effect of curing periods on disease occurrence, four periods (1, 3, 6 and 9 weeks) of curing were applied on Haryeong tubers harvested from the highlands (800 m a.s.l) in September. Tubers were stored at $2-3^{\circ}C$ and 80-90% RH for 6-7 months and were visually checked for disease occurrence. Tuber infection was characterized by barely visible small black spots on tubers and dark sooty lesions in stolon end of tubers. Another symptoms were observed on the upper surface of tubers which showed irregular, small to large, and depressed areas of brown to blackish skin with necrotic lesions inside. Results showed decrease in black dot depending on the curing period that ranges 18-48, 3-35, 0-14 and 0-3% at 1, 3, 6 and 9 weeks curing, respectively. During the storage, however, percentage weight loss of tubers and percentage of tubers with sprouts increased slightly with increasing the curing period from 1-3 to 6-9 weeks.

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Stem Rot of Kalanchoe Caused by Phytophthora nicotianae (Phytophthora micotianae 에 의한 칼랑코에 역병)

  • 한경숙;이중섭;지형진
    • Research in Plant Disease
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    • v.7 no.1
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    • pp.8-10
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    • 2001
  • A stem and root rot disease of kalanchoe (Kalanchoe sp.) which is a succulent plant that provides consumers with a durable flowering pot was found in Koyang, Kyounggi province, Korea in May 1998. We found that stems and roots of potted kalanchoe had dark brown spots at the soil level. The causal organism was identified as Pjytophtora nicotianae on the basis of mycological characteristics. The fungus produced markedly papillate, ovoid to spherical sporangia, and abundant chlamydospores. Sporangia were 20∼48$\times$24∼64㎛(avg. 35.0$\times$47.3㎛) in size, and optimum temperature for the mycelial growth of the isolate was 30$\^{C}$. The fungus showed relatively different pathogenicity to 14 kalanchoe cultivars including K. blossfelana cv. Florus. cultivars florsu, calypso, Maya, and Redsing were susceptible to thedisease in root dip inoculation. This is the first report demonstrating the stem rot on kalanchoe caused by P. nicotianae in Korea.

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MRI Findings of Intramuscular Foreign Body Injection: A Case Report (근육 내 이물질 주사의 자기 공명 영상 소견: 증례 보고)

  • So, Seong Yong;Kim, Hyun-Joo;Choi, Deuk Lin;Hong, Seong Sook;Chang, Yun-Woo;Park, Sung Tae
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.1
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    • pp.59-62
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    • 2013
  • There are various types of foreign body reactions, such as inflammation, edema, fluid collection, hematoma, infection, abscess and granulomas. There are various imaging findings according to types of foreign bodies and depending on the lapse of time. Therefore, correct diagnosis of a foreign body reaction is difficult and easily confused with soft tissue neoplasm. The MRI is ideal for the detection of foreign bodies regardless of radiolucency or acoustic impedance. It is especially very useful in the evaluation of the surrounding tissue reaction. The authors report a case of a 26-year-old female patient with both forearm swelling due to self-injection of a mixture of powdered tablets and saline. The lesion shows numerous internal T1 and T2 dark signal intensity micro-spots with surrounding fluid collection, which are diagnosed as foreign bodies with surrounding inflammatory changes during an operation.

A Study on the Development of Traditional Korean Paper Changphanji by the Bast Fiber of Paper Mulberry (닥나무의 인피섬유(靭皮纖維)를 이용(利用)한 전통(傳統) 한지장판지(韓紙壯版紙) 개발(開發)에 관(關)한 연구(硏究))

  • Cheon, Cheol
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.4
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    • pp.53-64
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    • 1990
  • This study was carried out to develop the traditional korean paper changphanji from the bast fiber of paper mulberry The results obtained were as follows: 1. The variations in the basis weight were remarkable, but there were no significant adverse effects on the tensile strength and thickness. 2. The stamping have contributed to the improvement of smoothness and the control of thickness. The automatic pressing system recommended to obtain good control of thickness. 3. The average density of the traditional korean paper changphanji was 1.06g/$cm^3$. 4. The changphanji developed in this study gave a clude, but excellent toughness and warm feeling. Some fiber lumps, dark spots and bamboo, screen marks were also obserded. 5. The tensile strength of four-fold sheet changphanji is highest and those of two-fold sheet changphanji is lowest. the lengthwise tensile strength was higher than crosswise one due to the fiber. 6. The elongation of three-fold sheet changphanji was highest 7. The water absorption of all products ranged from 11.3g/$m^2$ to 17.5g/$m^2$. 8. The wight loss by abrasion was 34.0%(four-fold sheet) 31.6%(three fold sheet), 31.0% (two-fold sheet)respectively. 9. Based on the results obtained. tensile strength and elongation, the four-fold sheet was excellent. the use of the bast fiber of paper mulberry as a raw material is attractive point which can not obtained from the commercial changphanji made from other raw materials.

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Occurrence of Sword bean Scab Caused by Cladosporium cucumerinum in Korea

  • Kwon, Jin-Hyeuk;Kang, Soo-Woong;Park, Chang-Seuk
    • Mycobiology
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    • v.28 no.1
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    • pp.54-56
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    • 2000
  • A black scab disease occurred on sword bean (Canavalia gladiata) in plastic film houses around Chinju area during the spring season of 1999. The disease started from flower bud, then moved to flower stalk, pod, petiole, cirrus, stem and leaves. The lesions started with small dark brown spots then were gradually expanded. Severely infected plants reached 37.4% of whole plant covered with scab. Numerous conidia were produced on the diseased flower disk, pod, floral axis, stem and leaves. Most of the conidia were appeared to be readily dispersed in the air, but the mycelia were not suggested causing of sooty mold by ectoparasitism. A fungus was isolated from the diseased stem, and inoculated to healthy plants to satisfy the Koch's postulates and proved the fungus was the causal agent of the disease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated. The conidia were $3.9{\sim}34.1{\times}2.7{\sim}5.1\;{\mu}m$ in size and formed in long branched chains on the erected conidiophores which were pale olivaceous brown and variable in length between $7.2{\sim}210.7\;{\mu}m$ in size. Ramoconidia were $7.6{\sim}29.2{\times}3.2{\sim}14.4\;{\mu}m$ in size. The fungus was identified as Cladosporium cucumerinum based on the above morphological characteristics. The optimum temperature for mycelial growth and conidial formation was about 15 to $25^{\circ}C$. Cladosporium scab of sword bean caused by the fungi has not been reported in Korea previously.

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First Report of Black Rot Caused by Diplodia seriata on Apple (Diplodia seriata에 의한 사과 검은썩음병 발생보고)

  • Kim, Young Soo;Yun, Yun Joo;Jeon, Yongho
    • Research in Plant Disease
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    • v.24 no.4
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    • pp.321-327
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    • 2018
  • In 2018, symptoms of black rot on apple (Malus pumila var. dulcissima KOIDZ) cv. Fuji were observed in Yeongcheon-si, Korea. The fruit decay symptoms consisted of purple pimples spots, black rot around the seed cavity (calyx end), mummified fruit. To isolate the causal agent, small fragment (2 to 3 mm) of decayed tissue from the lesion margin were placed on WA or PDA. Fungal colonies on PDA produced dense white aerial mycelium, becoming dark gray with age. Pycnidia and conidia were observed under a light microscopy. The shapes of conidia were aseptate, ovoid, rounded at both ends, and $21.7-28.3{\times}9.9-15.3{\mu}m$. Based on morphological and cultural characteristics, this fungus was identified as Diplodia seriata. To confirm its identity, two loci (ITS and ${\beta}$-tubulin) were sequenced for molecular identification. BLAST searches indicated 100% identity with D. seriata. A pathogenicity test was conducted with isolates on Fuji apples. The apples were inoculated with mycelial plugs (5 mm) from 7-day-old cultures of the putative pathogens. All inoculated apples developed rot symptoms identical to the original symptoms, from which D. seriata were reisolated, fulfilling Koch's postulates. This study is the first report of black rot caused Diplodia seriata on apple.

First Record of Bothus pantherinus (Bothidae, Pleuronectiformes) from Korea (한국산 둥글넙치과(Bothidae) 어류, Bothus pantherinus의 첫기록)

  • Si-Yeong Jeong;Jin-Koo Kim
    • Korean Journal of Ichthyology
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    • v.35 no.1
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    • pp.44-49
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    • 2023
  • A single specimen of the genus Bothus (family Bothidae) was collected for the first time at the intertidal zone of Moseulpo Port, Daejeong-eup, Seogwipo-si, Jejudo Island, on 14 August 2022. The specimen was identified as Bothus pantherinus in having following morphological traits: dark spots and ring-shaped patterns near eyes and the pectoral fins, one distinct spot in the center of the lateral line, 75 lateral line scales, and seven hourglass shaped supracranial pterygiophores. As a result of analyzing 603 bp of mitochondrial DNA COI sequences, our specimen was perfectly matched to those of B. pantherinus registered in NCBI. It has been known that the species is widely distributed throughout the Indo-Pacific Ocean from Red Sea to Hawaiian (32 degrees north to 32 degrees south), but this study revealed that its distribution expanded to the waters of Jejudo Island (33 degrees north), Korea. We propose its new Korean name "Beot-kkoch-mu-nui-dung-geul-neob-chi".