• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.298-304
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• 2018

A single specimen of Gymnothorax pseudothyrsoideus (424.0 mm TL) belonging to the family Muraenidae, order Anguilliformes, was collected from Jeju Island, Korea, for the first time. The specimen is characterized by jaws closing completely, canine teeth on jaws, teeth not exposed when mouth is closed, ovoid posterior nostril, and body color ranging from yellowish brown to brownish with small dark spots aggregating to form larger spots that from approximately four irregular rows along the body. A comparison of mitochondrial DNA 16S rRNA sequences indicated that this specimen corresponds well with G. pseudothyrsoideus (K2P distance, d=0.002) but differs from other Gymnothorax species (11.9-13.7%). Therefore, the new Korean name "Geu-mul-nun-gom-chi" is proposed for the species G. pseudothyrsoideus.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.651-653
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• 1998

A destructive anthracnose of safflower has severely occurred at Kyeongsangnam-do Agricultural Research and Extention Services in 1998. Incidence of the disease surveyed at 12 fields in Chinju, Sanchong and Hamyang was ranged fro 55.7 to 85.4%. Small irregular yellowish to brown spots appeared on all parts of the plant at initial infection stage and the spots enlarged or united into larger irregular to cylindrical black lesions with hollows. Above portions of infected stems were often blighted and pink colored conidial masses were colonized on the lesions. The causal fungus consistently isolated from the infected tissues were identified as Colletotrichum acutatum by following characteristics. The fungus grew well on PDA at 15~3$0^{\circ}C$ developing apricot to salmon color. Conidia were single-celled, colorless, fusiform and bisectioned and measured as 8~18$\times$3~5 ${\mu}{\textrm}{m}$. Brownish appressoria were cylindrical or ovate and sized as 5~10$\times$4~8 ${\mu}{\textrm}{m}$. Optimum temperature for growth and germination of conidia was recorded at $25^{\circ}C$ and at least 6 hours were required for infection to the host plants. Over 90% conidia were germinated and all plants were infected by artificial inoculation by 24 hours at $25^{\circ}C$. This is the first report of safflower anthracnose caused by C. acutatum in Korea.

• Research in Plant Disease
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• v.26 no.4
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• pp.279-282
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• 2020

In 2019, symptoms of Botrytis mold on the peony (Paeonia lactiflora Pall.) 'Sarah Bernhardt' were observed during a survey of the commercial greenhouses of Gangjin County, South Korea. The initial symptoms, small brown spots, were observed mainly at the leaf margins. The lesions extended to the interior of leaves forming irregular spots in which abundant conidia developed. Fungal colonies were obtained from surface-sterilized tissue excised from growing edges of the lesions that were transferred to potato dextrose agar. Melanized irregular sclerotia were formed in these colonies after 40 days at 8℃. Molecular phylogeny based on sequences of genes for glyceraldehyde-3-phosphate dehydrogenase, heat-shock protein 60, and RNA polymerase subunit II were highest for the PBC-2 isolate to the type strains of Botrytis cinerea, rather than other Botrytis species associated with peony diseases. Following Koch's postulates, healthy Sarah Bernhardt plants were inoculated with a foliar application of conidial suspensions of the isolate PBC-2. Following incubation under humidity with a 12 hr photoperiod for 7 days, symptoms developed on the leaf margins that were identical to those observed in the greenhouses. This study is the first report of Botrytis blight caused by B. cinerea on peonies grown in commercial greenhouses in South Korea.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.147-154
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• 2003

Agronomic characters of the 361 Korean adzuki beans(Vigna angularis (Willd.) Ohwi & Ohashi) collected in Korea were examined. Korean adzuki beans had predominantly up right growth habit types, followed by the intermediate types (15.3%) and the climbing types (6.9%). Round leaf type was the majority among the collections and followed by elliptical and xiphoid leaf type. Adzuki beans with yellow, light yellow and dark yellow flowers were 89.5％, 9.4％ and 1.1％, respectively. The 60.6% of the collections had red seeds and 26.9% had gray seeds. And collections with green seeds, white seeds mixed with gray spot, brown spots on red seeds, black spots on red seeds and dark gray spots on black seeds were also observed. Korean adzuki beans whose number of days from planting to flowering were 69∼75 days were the majority among 361 Korean adzuki beans. The number of days from flowering to majority were 41∼50 days and the number of days from planting to maturity were 111-120days. Adzuki beans having the stem length of 41-60 cm, the pod number per plant of 16-20 and the 100 seed weight of 8∼10 g were 50.2％, 40.2% and 30.5％ of collections, respectively.

• Research in Plant Disease
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• v.9 no.3
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• pp.159-161
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• 2003

Leaf spot diseases were found on safflower (Carthamus thinctorius) leaf in several fields located in Euisong-Gun, Gyengbuk province in Korea. The infected leaf rate of the diseases in surveyed area were different each years from 2001 to 2003 such as about 5%, 10%, and 30%, repectively. The typicla symptoms of diseases appeared first as small, light brown spots on leaves. And then spot turn dark brown and magnified. And yellow decoloration zone appeared surrounding dark brown spots. Mycological characteristics of Alternaria carthami, isolated from safflower mature leaf spot were dark gray colonies, conidiophores simple erect, septated, 40~80 ${\mu}m$ length; conidia solitary, straight, body size fo without beak length 40~100${\mu}m$, 10~15${\mu}m$ thick, Number of transverse septa 4~10 and longitudinal septa 4~7 ; beak with 2~4 septa, 30~65${\mu}m$ length. And A. alternata, isolated from old leaf were gray~dark gray colonies, conidiophores simple or branched, 20~110 ${\mu}m$ length; conidia long chaines, short conical or cylindrical beak, 2~6 transverse septa and several longitudinal septa, body size of without beak length 30~60 ${\mu}m$, 10~20 ${\mu}m$ thick ; beak length 5~35 ${\mu}m$. These are the first report on the leaf spot of safflower caused by Alternaria carthami, A alternata in Korea.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.101-104
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• 2016

Curvularia leaf blight of creeping bentgrass (Agrostis stolonifera) putting green by caused Curvularia trifolii was observed in Hapcheon, Korea. In July to September 2014, curvularia leaf blight developed on leaf blades of creeping bentgrass as small water-soaked lesions that subsequently turned into dark-colored, necrotic spots. The spots were expanded and became gray, grayish-brown, or light brown, circular to oblong lesions with purple to dark brown borders that often were surrounded by a yellow halo. The necrotic lesions coalesced, became irregular in shape and caused tip or complete blighting of the leaves. Blighted leaf blades appeared grayish-white to tan. The fungus was identified by morphological characters and 16S rDNA sequencing as C. trifolii. Conidia of the pathogen were short, with predominantly 3-septa, straight or often curved, with end cells frequently paler than intermediate cells. Size of the 3-septate conidia in culture are $26{\sim}28{\times}11{\sim}12{\mu}m$. Pathogenicity of the fungus was proved by artificial inoculation on the host. This is the first report of C. trifolii causing leaf blight on creeping bentgrass in Korea.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.201-205
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• 2016

In August 2015, leaf spot symptoms were observed on Korean gondre thistle (Cirsium setidens) in Youngwol, Korea. During the early stage, the symptoms appeared as one or more small gray-brown to brown spots on plant leaves. The spots showed extensive enlargement over time and eventually became large dark brown to black lesions on the whole leaf. Stemphylium species were consistently isolated from affected leaves. All isolates were identified as S. lycopersici, S. solani, or S. xanthosomatis based on morphological and cultural characteristics. The isolates were confirmed as S. lycopersici based on a multilocus sequence analysis using the ribosomal internal transcribed spacer (ITS) region, elongation factor 1, GAPDH (glyceraldehyde-3-phosphate dehydrogenase), and the noncoding region between the vacuolar membrane ATPase catalytic subunit A gene and a gene involved in vacuolar biogenesis. Pathogenicity was tested by spore suspension inoculation on wounded or unwounded gondre leaves. The lesions were observed on inoculated leaves within 3 days after inoculation, regardless of wound. To our knowledge, this is the first report of the leaf spot on gondre thistle caused by S. lycopersici in Korea or elsewhere.

• Research in Plant Disease
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• v.15 no.1
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• pp.41-45
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• 2009

In order to study a relationship between soil nutrients and rice brown spot occurrence, paddy field soils, rice grains and straws collected from different paddy fields with different disease degrees of brown spots were analyzed for inorganic nutrients. Brown spot was prevalent in the rice grown in nutrient-deficient soils, which is especially low in macronutrient elements (phosphoric acid, potassium, silicic acids) and micronurients (calcium, magnesium). The soil, however, was high in sodium while organic nutrients and pH level were similar to others. The rice straws with severe brown spot were low in inorganics such as ferrous, copper, T-N, and $P_{2}O_{5}$ while the rice grains with brown spot were low in ferrous, MgO, Zn, and Mn. In the analysis of field type and nitrogen level, the highest disease severity was found in sandy-type field soil, followed by salty-type field soil and disease severity decreased as application level of nitrogen fertilizer increased. As a summary, the most important factor for effective brown spot control in rice is maintenance of proper nutrients in sandy-type field and control of sodium level in salty-type field soil.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.183-188
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• 1979

The study has been carried to describe a new disease of strawberry in Korea, which was found in 1977 at Kimhae. Symptom of the disease occurred mainly on leaves as showing large annular brown spots or 'V' shaped brown lesions. Many of dark pycnidia were observed from the both side of old lesions. The pathogen was identified as Dendrophoma obscurans (Ell. & Ev) Anderson which has not been described in Korea as a pathogen of strawberry disease. The common name of the disease was given, temporaly, as Annular leaf blight of strawberry. In the laboratory study, light was necessary for the production of pycnidia and potato dextrose agar was the best media for tile pycnidia formation. There were some difference on resistance to the disease among 48 tested strawberry varieties though none of them shelved highly resistant reaction, and the older leaves showed more susceptible reaction than younger ones.

• Mycobiology
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• v.29 no.2
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• pp.110-112
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• 2001

A black scab was observed on strawberry(Fragaria ananassa) in plastic film houses around Jinju area during the winter of 2000. The disease started from leaves then moved to calyx and runner. At the beginning, the infected area started with small dark brown spots then gradually expanded. The pathogenic fungus was purely isolated from the diseased leaves, calyx and runner. The fungus was inoculated to test Koch's postulates and proved to be the causal agent of the disease. The isolated fungus grew readily on potato dextrose agar, forming dark green to dark gray colonies. The optimum temperature for mycelial growth was about $25^{\circ}C$. The diameter of growing hyphae was $3.8{\sim}5.6{\mu}m$. Conidia were ellipsoidal, ovoid or subspherical, mostly one-celled but occasionally septate. The size of conidia were $4.1{\sim}11.7{\times}3.8{\sim}5.3$ 1-cell, $9.3{\sim}18.8{\times}4.0{\sim}7.4{\mu}m$ 2-cell and formed in long branched chains on the erected conidiophores which were dark brown and variable in length between $28.8{\sim}236.2{\times}3.0{\sim}6.2{\mu}m$ in size. The fungus was identified as Cladosporium herbarum on the basis of its morphological characteristics. The black scab disease of strawberry caused by C. herbarum has not been reported in Korea previously.