• Korean journal of applied entomology
• /
• v.26 no.2 s.71
• /
• pp.113-115
• /
• 1987

Out of twelve fungicides evaluated in vitro and in vitro to manage rust and leaf spot diseases: Biloxazole was found to control both the diseases simultaneously and also increased the yield of peanut.

• Mycobiology
• /
• v.43 no.3
• /
• pp.351-353
• /
• 2015

Farfugium japonicum is used in traditional medicine and as an edible herb in China and Korea. In July 2013, leaf spots were observed in F. japonicum seedlings at Ulleung Island, Gyeongsangbuk Province, Korea. Early symptoms on the leaf adaxial surface included roughly circular yellow spots that later developed brown, necrotic centers. The aecia were hypophyllous, cupulate, yellowish, $180{\sim}430{\mu}m$ in diameter, clustered, and erumpent with a peridium with a recurved margin. The aeciospores were globoid, $14{\sim}17{\times}13{\sim}16{\mu}m$, light yellow or colorless, and densely verrucose. The 28S rDNA sequence of the isolate was identical to each other and shared 99% identity with Puccinia caricis. This is the first report of rust caused by P. caricis in F. japonicum in Korea or elsewhere in the world.

• Korean Journal Plant Pathology
• /
• v.11 no.3
• /
• pp.282-284
• /
• 1995

Grey leaf spot on tomato plants was first observed in Sedo-myeon, Puyo-kun, Chungnam province of Korea in 1994. This disease which had not been reported before in Korea exhibited different symptoms from those of other leaf spot diseases on tomato plants. The symptoms were characterized by small irregular-shaped spots on leaves at the initial stage of the infection, subsequent spread and coalescence of the spots throughout the leaves with ultimate necrosis, and abscission from the plants. When healthy tomato plants were inoculated with a conidial suspension of the fungus isolated from the lesion of a diseased plant in a field, the same characteristic symptoms as those in the field were produced. Furthermore, the same pathogen could be reisolated from the lesions formed buy the inoculation. Conidial characteristics of the pathogen were as follows; oblong shape with constricted 3 transverse septa, round-shaped base, round- or point-shaped apex, size of 45~75$\times$12.5~17.5 ${\mu}{\textrm}{m}$, and 3.5 : 1 ratio of length to width. The pathogen was identified as Stemphylium lycopersici and thus this is the first report on the occurrence of grey leaf spot disease on tomato plants caused by s. lycopersici in Korea.

• Mycobiology
• /
• v.44 no.3
• /
• pp.187-190
• /
• 2016

In July 2015, diseased leaves of black chokeberry (Aronia melanocarpa) were observed in Danyang and Gochang, Korea. The symptoms appeared as circular or irregular brown leaf spots, from which Alternaria tenuissima was isolated. The isolates were cultured on potato dextrose agar, and their morphological characteristics were observed under a light microscope. The colonies were whitish to ash colored. The pathogenicity test on healthy black chokeberry leaves produced circular brown spots, in line with the original symptoms. Molecular analyses of the ITS, GPD, RPB2, and TEF genes were conducted to confirm the identity of the pathogen. The phylogeny of the multi-gene sequences indicated that the causal agent was A. tenuissima. This study is the first report of A. tenuissima leaf spot on black chokeberry (A. melanocarpa).

• The Plant Pathology Journal
• /
• v.19 no.4
• /
• pp.200-202
• /
• 2003

Leaf spots were first observed on watermelon (Citrullus vulgaris Schrad) under polyethylene film-covered green-house in November 2002. Symptoms appeared as dark-brown circles or large irregular spots on the leaves of watermelon. Occasionally, zonal growth of the lesions was observed. Under humid conditions, small black sclerotium-like bodies (sporodochia) were produced on the surface of the lesions. The sporodochia on leaf lesions were sessile, polymorphic, variable in size, 35-850 $\mu\textrm{m}$ in diameter, and 30-470 $\mu\textrm{m}$ in depth. Conidia in sporodochium were black in mass, one-celled, rod-shaped, with rounded ends, hyaline, guttulate, and measured 6-8$\times$1.6-2.2 $\mu\textrm{m}$ in size. The pathogen was identified as Myrothecium roridum Tode ex Fr. This is the first report of Myrothecium leaf spot on watermelon naturally occurring in commercial greenhouses.

• Applied Biological Chemistry
• /
• v.36 no.6
• /
• pp.502-509
• /
• 1993

In Ulrung floral community the growing environments and nutritive values of wild garlic was investigated. The wild garlic, grown for $3{\sim}4\;years$ in community area, were able to develope bulbs. The bulbs with 2 leaves had the highest ratio of propotion as 75.1% of share among the distribution of bulbs with completely developed leaves and 1 leaf-bulbs and 3 leaves-bulbs had 19.6% and 5.3%, respectively. Also the 2 or 3 leaves-bulbs indicated the better growth states in the part of shoot and bulbs than 1 leaf-bulbs, and there was a significant defferences in each growth between 2 leaves-and 3 leaves-bulbs. On the wild garlics we cannot find out insect injuries. However, there was deseases with symptoms of leaf-spots and lesion from May to June. At first it made a small spots on the leaves, followed by senescence at arrounding area of spots, and then it expanded to whole leaf. This pathogenic bacterium was supposed to be a member of Aristastoma. The contents of crude protein, fat, and carbohydrate in each portion of wild garlics decresed in the order of shoot, expanded leaves and bulbs. On the contrary, crude fibers increased in the same order and so it is not suitable for human consumption nutritional value. However, because the shoots of wild garlics have more than the other Allium sp., the shoots will be a good quality food stuff.

• Research in Plant Disease
• /
• v.16 no.1
• /
• pp.97-100
• /
• 2010

Angular leaf spot of strawberry caused by Xanthomonas fragariae occurred sporadically in the farmers open field at Sugok-myon, Jinju city, and greenhouse at Okjong-myon, Hadong-gun, Gyeongnam province, Korea. Typical symptoms of angular leaf spot initially appeared as a minute, water-soaked, rotted lesion on the lower leaf surface and the minute spots expanded to form angular leaf spots, usually delimited by small veins. The lesion was translucent under the transmitted light and dark green under reflected light. The slow growing pathogen was a gram-negative, motile bacterium with single polar flagellum, and producing yellowish orange pigment on YDC medium. It showed very strong pathogenicity on the leaves of strawberry. On the basis of biological characteristics and pathogenicity test on host plants, the bacteria was identified as a Xanthomonas fragariae. This is the first report on angular leaf spot of strawberry caused by X. fragariae in Korea.

• BMB Reports
• /
• v.42 no.7
• /
• pp.450-455
• /
• 2009

The "stage albinism line of winter wheat" FA85 was a specific natural mutant strain on leaf color. This physiological mutation was controlled by cytogene. In order to reveal the genetic and biochemical mechanism of albinism, 2-DE was used to investigate the difference of chloroplast protein expression pattern between FA85 and its parent wheat Aibian 1. From the results of 2-DE gels analysis, approximately 683 spots were detected on each gel, and 57 spots were expressed differently at least two-fold. Using MALDI-TOF/TOF MS, 14 of 57 spots were identified, which could be categorized into four classes: carbon metabolism, energy metabolism, defense/stress response and signal transduction. Compared with the parent wheat, the expression of ATPase-$\gamma$ and GP1-$\alpha$ was up-regulated in FA85, and of other proteins was down-regulated. Together, we concluded that the expression of chloroplast proteins had changed obviously in FA85, which might be related to the leaf color mutant.

• Plant Disease and Agriculture
• /
• v.5 no.2
• /
• pp.105-110
• /
• 1999

Bacterial leaf spot by Xanthomonas campestris pv. vesicatoria has been known to cause serious problem in red pepper in Korea. However recent survey showed that most smptoms in the leaves were mixed with two different symptoms one was leaf spot and the other was canker. bacteria isolated from canker were identified as Clavibacter michiganensis subsp. michiganensis on the basis of biochemical and physiological characteristics. The causal bacteria were non-motile rod-shaped and Gram-positive. The lesions on pepper leaves appeared at first as small blisters or pimple-like white spots which enlarged in size at a later stage. The centers of some of the spots became necrotic and brown and were surrounded by a white halo. Pathogenicity tests were performed on pepper cv. Alchan seedling by spraying of bacterial suspension. During 1997 and 1998 total 17% of 527 fields surveyed were infected by C. michiganensis subsp. michiganensis. The canker of red pepper caused by C. michiganensis subsp. michiganensis was first identified in this study in Korea, and new name "gueyangbyung" was tentatively given to the disease.

• Research in Plant Disease
• /
• v.29 no.1
• /
• pp.60-63
• /
• 2023

During disease surveys from 2019 to 2021, the authors frequently encountered leaf spot symptoms on Fischer's ragwort plants growing at fields at six locations of Gangwon Province, Korea. The symptoms displayed brown to dark brown, circular or irregular spots on the plant leaves. The disease surveys at the six locations revealed 1-90% of diseased leaves of the plants. Phoma sp. was dominantly isolated from the diseased leaf lesions. Seven single-spore isolates of the fungus were selected and identified as Didymella ligulariae by investigation of their cultural, morphological, and molecular characteristics. Artificial inoculation test to Fischer's ragwort leaves was conducted with three isolates of D. ligulariae. The inoculation test revealed that the tested isolates cause leaf spot symptoms in the plants similar to the natural ones. The fungal pathogen has never been reported to cause leaf spot in Fischer's ragwort. Leaf spot of Fischer's ragwort caused by D. ligulariae is first reported in this study.