• Title/Summary/Keyword: Dark spots

Search Result 158, Processing Time 0.028 seconds

Bacterial Canker of Japanese Apricot (Prunus mume) Caused by Pseudomonas syringae pv. morsprunorum (Pseudomonas syringae pv. morsprunorum에 의한 매실의 세균성궤양성)

  • Kim Doo Young;Han Hyo Shim;Koh Young Jin;Jung Jae Sung
    • Research in Plant Disease
    • /
    • v.11 no.2
    • /
    • pp.135-139
    • /
    • 2005
  • Bacterial canker of Japanese apricot (Prunus mume Sieb. et Zucc.) was found in all orchards located at southern area of Korea. Typical symptoms were characterized by dark spots formed on fruits, brown lesions on leaves, and bacterial exudate oozed out of the cracked bark of diseased tree. Thirty-eight isolates from 16 different areas were identified on the basis of biochemical and physiological characteristics (LOPAT and GATTa test) and also on the basis of 165 rDNA and ITS sequences. Pathogenicity tests confirmed that bacterial canker of Japanese apricot in Korea is caused by Pseudomonas syringae pv. morsprunorum.

Gray Leaf Spot in Peppers Caused by Stemphylium solani and S. lycopersici

  • Kim, Byung-Soo;Yu, Seung-Hun;Cho, Hyun-Jung;Hwang, Hee-Suk
    • The Plant Pathology Journal
    • /
    • v.20 no.2
    • /
    • pp.85-91
    • /
    • 2004
  • A disease causing severe leaf spots in pepper plants has been observed in northern Gyeongbuk and Gangwon provinces in Korea since 1994. The current study diagnosed the disease as gray leaf spot caused by Stemphylium solani Weber and S. lycopersici (Enjoji) Yamamoto, both of which are pathogenic in pepper and tomato plants. Although the disease has been found in almost all areas where peppers are grown, it is more severe in mountain terrains where the nights are cool. Both species of pathogenic fungi were found to sporu-late profusely on V-8 juice agar in plastic or Pyrex glass Petri dishes, although not in domestically-produced glass Petri dishes, when cultured at $20^{\circ}C$ under irradi-ation from a daylight fluorescent lamp with a 12-hour light and dark alternation. The domestically-produced glass Petri dishes, which are made of window glass, were found to block near ultraviolet wavelengths, around and below 300 nm, which explained why the fungi did not sporulate. However, sporulation decreased at above $25^{\circ}C$ and most isolates failed to sporulate above $27^{\circ}C$. The worst level of disease was obtained when the inoculated plants were incubated with a $15^{\circ}C$ night and $20^{\circ}C$ day temperature regime relative to 4 night/day temperature combinations (15/20, 20/25, 25/30, and 30/35$^{\circ}C$).

A Policy Proposal for the Korean Collaboration of Eastern and Western Medicine according to a model of the Chinese Integrative Medicine (중국(中國) 중서의결합(中西醫結合)모형에 따른 한국(韓國)의 한양방협진(韓洋方協診) 정책(政策) 제언(提言))

  • Park, Jeong-Seok;Shin, Byung-Chul;Kim, Chun-Bae;Jeong, Tae-Young;Lee, Yeon-Weol;Cho, Chong-Kwan;Yoo, Hwa-Seung
    • Journal of Haehwa Medicine
    • /
    • v.19 no.1
    • /
    • pp.1-7
    • /
    • 2010
  • Melasma is a common disorder that causes dark colored patches. It generally causes brown spots on the face, especially on the forehead, cheeks, and upper lips. The pattern of patches has bilateral symmetry in yellowish-brown to gray-brown colors. It is much more common in women than in men. Melasma is considered to be caused by environmental and physical constitutional factors and often occurs when a woman's hormone changes by pregnancy or the use of oral contraceptive pills. It is important to combine oriental medicine and Sasang constitutional medicine for treatment of Melasma. Normal treatment of Melasma includes warming oneself, removal of the emotional stress factors, and good nutrition.

Characterization of Virulence Function of Pseudomonas cichorii Avirulence Protein E1 (AvrE1) during Host Plant Infection

  • Huong, Duyen Do Tran;Rajalingam, Nagendran;Lee, Yong Hoon
    • The Plant Pathology Journal
    • /
    • v.37 no.5
    • /
    • pp.494-501
    • /
    • 2021
  • Pseudomonas cichorii secretes effectors that suppress defense mechanisms in host plants. However, the function of these effectors, including avirulence protein E1 (AvrE1), in the pathogenicity of P. cichorii, remains unexplored. In this study, to investigate the function of avrE1 in P. cichorii JBC1 (PcJBC1), we created an avrE1-deficient mutant (JBC1ΔavrE1) using CRISPR/Cas9. The disease severity caused by JBC1ΔavrE1 in tomato plants significantly decreased by reducing water soaking during early infection stage, as evidenced by the electrolyte leakage in infected leaves. The disease symptoms caused by JBC1ΔavrE1 in the cabbage midrib were light-brown spots compared to the dark-colored ones caused by PcJBC1, which indicates the role of AvrE1 in cell lysis. The avrE1-deficient mutant failed to elicit cell death in non-host tobacco plants. Disease severity and cell death caused by JBC1ΔavrE1 in host and non-host plants were restored through heterologous complementation with avrE1 from Pseudomonas syringae pv. tomato DC3000 (PstDC3000). Overall, our results indicate that avrE1 contributes to cell death during early infection, which consequently increases disease development in host plants. The roles of PcJBC1 AvrE1 in host cells remain to be elucidated.

First Record of a Goby, Callogobius shunkan (Perciformes: Gobiidae) from the Southern Coastal Waters of Jejudo Island, Korea (제주도 남부 연안 해역에서 채집된 농어목 망둑어과 한국첫기록종, Callogobius shunkan)

  • An, Jung-Hyun;Kim, Byung-Jik;Kim, Sang-Kil
    • Korean Journal of Ichthyology
    • /
    • v.32 no.4
    • /
    • pp.251-256
    • /
    • 2020
  • We described the first record of Callogobius shunkan from Korea, based on two specimens (54.9~66.1 mm in standard length) collected from the southern coastal waters of Jejudo Island. These specimens were characterized by prominent papillae ridges on the head, including postnasal and postorbital rows, well-developed pelvic frenum, dark brownish head, scattered whitish flecks on the body, and three blackish spots on the basal portion of dorsal fins. We proposed a new Korean name, "Ju-reum-mang-dug" for the species.

Occurrence and Characterization of Leaf Spot Caused by Septoria melissae on Lemon Balm in Korea

  • Yang, Seon-Ah;Choi, In-Young;Ju, Ho-Jong;Lee, Kui-Jae;Galea, Victor;Shin, Hyeon-Dong
    • Mycobiology
    • /
    • v.48 no.6
    • /
    • pp.495-500
    • /
    • 2020
  • Leaf spot on lemon balm is frequently observed in Korea, causing considerable damage to crops. In 2014 and 2015, the occurrence of leaf spot was observed in several production greenhouses at Suwon, Gongju, and Namwon in Korea. Symptoms on lower leaves initially developed as small, distinct, discolored lesions, which enlarged progressively turning into dark brown, angular spots surrounded by purplish-brown margins. Based on the morphological characteristics and sequence analysis of actin (ACT), translation elongation factor 1-alpha (EF-1α), internal transcribed spacer (ITS), 28S nrDNA (LSU), and RNA polymerase II second largest subunit (RPB2), the fungus associated with the lemon balm leaf spot was determined as Septoria melissae. To the best of our knowledge, this is the first report of lemon balm leaf spot caused by S. melissae in Asia as well as in Korea.

First record of Chaetodon vagabundus Linnaeus, 1758 (Pisces, Chaetodontidae) collected from Jeju Island, Korea (한국 제주도에서 출현한 나비고기과 어류 1미기록종, Chaetodon vagabundus Linnaeus, 1758)

  • LEE, Yu-Jin;KIM, Jin-Koo
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.57 no.2
    • /
    • pp.127-133
    • /
    • 2021
  • A single specimen of Chaetodon vagabundus Linnaeus, 1758 belonging to the family Chaetodontidae was collected on September 8, 2013 in Yerae-dong, Seogwipo-si, Jeju Island, Korea. The morphological characteristics of C. vagabundus are similar to C. auriga and C. auripes in having dark vertical stripes cross the eye, but differs from C. auriga, which has high dorsal fin extended between spine and soft rays without concavity and has blotch of circle in dorsal fin, and from C. auripes which has yellow body, big of eye proportion and a black stripe along the caudal peduncle during the immature stage. C. vagabundus has eye-like black spots on dorsal fin and black vertical stripe extended from the anterior dorsal soft ray to the middle of the anal fin along the caudal peduncle. Molecular analysis results showed that our specimen perfectly matched C. vagabundus in the mitochondrial DNA COI sequences. Therefore, we use the Korean name, "Hwang-jul-na-bi-go-gi" for C. vagabundus proposed by Kim et al. (2020).

First Report of Leaf Spot Disease Caused by Cladosporium pseudocladosporioides on Morus alba in South Korea

  • Heo, Jung-In;Oh, Ji Yeon;Lee, Dong-Hyeon
    • Journal of Forest and Environmental Science
    • /
    • v.37 no.4
    • /
    • pp.338-340
    • /
    • 2021
  • Morus alba, known as White Mulberry, is one of the most common species of mulberry found in South Korea, along with M. australis, known as Korean Mulberry. During a routine survey to investigate fungal diseases on deciduous broad-leaved trees in 2020, leaf spots were consistently observed on the White Mulberry in Sejong-si (36°30'12.8"N 127°17'34.5"E) and Wonju-si (37°15'29.6"N 128°11'37.9"E), South Korea, with a disease incidence of approximately 70 to 80%. Symptoms included circular, tan or necrotic lesions surrounded by a dark margin on leaves, which, in some cases, the lesions coalesced to form relatively large necrotic regions. The pathogen was successfully isolated from M. alba, and was identified as Cladosporium pseudocladosporioides based on the phylogenetic analysis and morphology. To the best of our knowledge, this is the first report of leaf spot disease on M. alba caused by C. pseudocladosporioides in South Korea.

The first record of the winter stonefly genus Mesyatsia Ricker & Ross, 1975 (Plecoptera: Taeniopterygidae) from Korea

  • Hwang, Jeong Mi;Hur, Jun Mi;Kang, Ji Hyoun;Bae, Yeon Jae;Muranyi, David
    • Journal of Species Research
    • /
    • v.10 no.4
    • /
    • pp.419-421
    • /
    • 2021
  • The genus Mesyatsia Ricker & Ross, 1975 is a small genus of the family Taeniopterygidae with only six species worldwide. This genus is mainly distributed in Asia, but has never been reported in Korea. In this paper, we report Mesyatsia makartchenkoi Teslenko & Zhiltzova, 1992 for the first time from the Korean Peninsula. The specimens were collected from Odaesan National Park, Bangtaesan Natural Recreation Forest, and Gariwangsan Natural Recreation Forest in Gangwon-do, South Korea by mainly Malaise traps and a few by sweep net. Some pharate larvae and adults crawling on the snow were also collected by handpicking. This species is characterized by the following features: pterostigma with dark spots; abdominal sternum 9 with vesicle; abdominal tergum 10 medially divided into two; subgenital plate strongly elongated, scoop-shaped, upcurved with tongue-shaped apex; cercus blunt. We provide materials, diagnosis for newly recorded species, and distributions. Additionally, we include a provisional key to the genera of Taeniopterygidae from Korea based on males.

Rear Vehicle Detection Method in Harsh Environment Using Improved Image Information (개선된 영상 정보를 이용한 가혹한 환경에서의 후방 차량 감지 방법)

  • Jeong, Jin-Seong;Kim, Hyun-Tae;Jang, Young-Min;Cho, Sang-Bok
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.54 no.1
    • /
    • pp.96-110
    • /
    • 2017
  • Most of vehicle detection studies using the existing general lens or wide-angle lens have a blind spot in the rear detection situation, the image is vulnerable to noise and a variety of external environments. In this paper, we propose a method that is detection in harsh external environment with noise, blind spots, etc. First, using a fish-eye lens will help minimize blind spots compared to the wide-angle lens. When angle of the lens is growing because nonlinear radial distortion also increase, calibration was used after initializing and optimizing the distortion constant in order to ensure accuracy. In addition, the original image was analyzed along with calibration to remove fog and calibrate brightness and thereby enable detection even when visibility is obstructed due to light and dark adaptations from foggy situations or sudden changes in illumination. Fog removal generally takes a considerably significant amount of time to calculate. Thus in order to reduce the calculation time, remove the fog used the major fog removal algorithm Dark Channel Prior. While Gamma Correction was used to calibrate brightness, a brightness and contrast evaluation was conducted on the image in order to determine the Gamma Value needed for correction. The evaluation used only a part instead of the entirety of the image in order to reduce the time allotted to calculation. When the brightness and contrast values were calculated, those values were used to decided Gamma value and to correct the entire image. The brightness correction and fog removal were processed in parallel, and the images were registered as a single image to minimize the calculation time needed for all the processes. Then the feature extraction method HOG was used to detect the vehicle in the corrected image. As a result, it took 0.064 seconds per frame to detect the vehicle using image correction as proposed herein, which showed a 7.5% improvement in detection rate compared to the existing vehicle detection method.