• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.338-340
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• 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.

• Plant Resources
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• v.4 no.1
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• pp.41-47
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• 2001

This study was conducted to investigate the occurrence of Soil borne wheat mosaic virus(SbWMV) in barley fields in Korea and to examine the host pathogenicity of SbWMV. By using the ELISA test, SbWMV was detected in the six regions : Suwon, Milyang, Jinju, Youngkwang, Iksan, and Chonju. SbWMV was isolated from the two strains, Albori strain from Jinju and Eunpamil strain from Milyang. SbWMV was collected from leaves showing mosaic, yellowing and necrosis stripes. SbWMV was inoculated mechanically on 1∼1.5 leaf stages with leaf-rubbing to identify the host pathogenicity of 36 Korean barley cultivars, a wheat cultivar, two rye cultivars, three Japanese barley cultivars and Chenopodium amaranticola. Viral sympoms of inoculated leaves appeared on moulted loaves about 4 to 6 weeks of inoculation. Baegdong and Tapgolbori, infected from Albori strain and Eunpamil strain infected from Samdobori showed much higher susceptibility than C. amaranticola and C. quinoa which showed ring spots and chlorotic spots respectively. Virus particles were observed by the electron microscope. They were rod-shapes, which are bipartite, of 142 nm or 281 nm in length with 20 nm diameter on infected leaves. Specific detection and identification of SbWMV was set up using the RT-PCR. PCR fragments of SbWMV(0.5kb) were obtained by using the designed primers for SbWMV RNA 2.

• Research in Plant Disease
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• v.13 no.2
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• pp.122-125
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• 2007

Leaf spot disease of Kalanchoe (Kalanchoe blossfeldiana) occurred at the farmer's vinly house in Gangseo-gu, Busan Metropolitan City, Korea, 2006. The diseased plants with typical symptom were collected and the casual agent were isolated. Its mycological characteristics and pathogenicity were examined. The results were as follows. The typical symptoms of the disease appeared as small brownish or dark brown spot on both sides of the leaves. The spots tended to develop from lower leaves. The spots gradually enlarged into conspicuous necrotic lesions 1-5 mm in diameter. Colonies of the causal fungus formed on potato dextrose agar were velvety, gray or grayish brown in color, Conidia were cylindrical or obclavate to oblong in shape, brown in color, $24{\sim}65\;{\times}\;12{\sim}23\;{\mu}m$ in size and had 1-4 transverse septa, The optimum temperature for growth of the fungus was about $25-30^{\circ}C$. Conidiophores were brown in color, $32{\sim}135\;{\times}\;4{\sim}8\;{\mu}m$ in size and had 1-7 transverse septa. The fungus was identified as Stemphylium lycopersici (Enjoji) Yamamoto based on its symptom and mycological characteristics. This is the first report of leaf spot of Kalanchoe caused by S. lycopersici in Korea.

• Research in Plant Disease
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• v.9 no.3
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• pp.149-152
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• 2003

Black leaf spot disease occurred on Dendrobium phalaenopsis grown in farmer's fields located in Bonggangmyon, Gwangyang-eup, Jeonnam, Korea. Black small spots occurred on leaves at initial stage of infection and the infected leaves turned yellow from the tip. The yellow leaves were falled, resulting in stem blighting or eventual death of the entire plant. White mycelial colony of the causal fungus grown on potato dextrose agarturned dark violet later and optimum temperature for the mycelial growth was $25^{\circ}C$. The causal fungus isolated from the black leaf spot on D. phalaenopsis was identified as Fusarium moniliforme based on the mycological characteristics and pathogenicity. The fungus also caused same symptoms on leaves of Phalaenopsis sp. and Cymbidium sp. as well sa D. phalaenopsis by wound inoculation. This is the first report on black leaf spot of D. phalaenopsis caused by F.moniliforme in Korea.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.211-215
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• 2000

Symptoms on 4 varieties of watermelons inoculated with watermelon mosaic potyvirus II isolated from watermelon (WMV-W) were severe mosaic and leaf malformation while those inoculated with cucumber green mottle mosaic tobamovirus from watermelon (CGMMV-W) were mild mosaic and chlorotic spots. Inoculation of the mixture of WMV-W and CGMMV-W produced extremely severe mosaic along with necrotic spots and general necrosis. Doubly infected plants were also stunted. Cells infected with WMV-W or CGMMV-W alone exhibited the intrinsically ultra-structural properties of each virus infection. WMV-W induced potyvirus-characteristic cylindrical inclusions in the cytosol. Virus particles were orderly aligned along the tonoplasts. CGMMV-W induced tobamovirus-characteristic stacked crystalline arrays of virus particles in the cytosol. Cells infected doubly with WMV-W and CGMMV-W contained striking cytopathic effects that were not present in single infection of each virus. The unique ring structure, nonagon, was that a single potyvirus particle was surrounded by 9 CGMMV-W tobamovirus particles.

• International Journal of Computer Science & Network Security
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• v.23 no.3
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• pp.57-66
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• 2023

Rice is an important food crop for most of the population in the world and it is largely cultivated in Pakistan. It not only fulfills food demand in the country but also contributes to the wealth of Pakistan. But its production can be affected by climate change. The irregularities in the climate can cause several diseases such as brown spots, bacterial blight, tungro and leaf blasts, etc. Detection of these diseases is necessary for suitable treatment. These diseases can be effectively detected using deep learning such as Convolution Neural networks. Due to the small dataset, transfer learning models such as vgg16 model can effectively detect the diseases. In this paper, vgg16, inception and xception models are used. Vgg16, inception and xception models have achieved 99.22%, 88.48% and 93.92% validation accuracies when the epoch value is set to 10. Evaluation of models has also been done using accuracy, recall, precision, and confusion matrix.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.43-51
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• 1988

$SO_2$ gas injuries for 19 varieties of 10 species of plants were investigated within a environmentally controlled growth chamber. Visible injuries were observed when exposing the plants either 0, 0.2, 0.4, 0.7 or 1.5ppm of $SO_2$ gas for 5 days from 9 : 00 to 17 : 00 everyday. The results obtained were as follows: 1. Light brown spots were shown on Raphanus sativus(Chunchu, Taeback, Jinjudaepyung), Brassica campestris(Manchun, Josaengmiho, Seoul, Jeonseung), and Capsicum annum(Searona, Hongsanho, Hongilpum); brown spots on Sesamum indicum(Pungnyun, Kwangsan); reddish brown shades on Cleosia cristata; and black brown spots on Perilla frutescens, Calendula officinalis, Chrysanthemum morifolium, and Salvia splendens, respectively. 2. The spotty injuries induced by $SO_2$ gas injuries for 19 varieties of 10 species of plants were investigated within a environmentally controlled growth chamber. Visible injuries were observed when exposing the plants either 0, 0.2, 0.4, 0.7 or 1.5ppm of $SO_2$ gas for 5 days from 9 : 00 to 17 : 00 everyday. The results obtained were as follows: 1. Light brown spots were shown on Raphanus sativus(Chunchu, Taeback, Jinjudaepyung), Brassica campestris(Manchun, Josaengmiho, Seoul, Jeonseung), and Capsicum annum(Searona, Hongsanho, Hongilpum); brown spots on Sesamum indicum(Pungnyun, Kwangsan); reddish brown shades on Cleosia cristata; and black brown spots on Perilla frutescens, Calendula officinalis, Chrysanthemum morifolium, and Salvia splendens, respectively. 2. The spotty injuries induced by SO₂ gas on Raphanus sativus, Callistephus chinensis, Capsicum annum, Perilla frutescens, Calendula officinalis, Salvia splendens, and Sesamum indicum; the many small spots on Chrysanthemum morifolium; and the brown shade on Celosia cristata appeared on the upper surface of the intervein, on the leaf apex area and on the entire upper surface of leaves, respectively. 3. Visual injuries of Capsicum annum(Chunchu), Perilla frutescens, Sesamum indicum(Pungnyun, Kwangsan), and Salvia splendens were developed at 0.4ppm of SO₂ gas fumigation. Brassica campestris(Jeonseung), Capsicum annum(Searona, Hongilpum), and Cleosia cristata, however, showed the injury at 1.5ppm of $SO_2$ gas concentration. 4. Based on the tolerance grade(time when the 1st injury appeared), Raphanus sativus, Perilla frutescens, Sesamum indicum, and Salvia splendens were the most sensitive plants and Chrysanthemum morifolium, Callistephus chinensis, Cleosia cristata, and Calendula officinalis were the plants most tolerant of $SO_2$ gas. gas on Raphanus sativus, Callistephus chinensis, Capsicum annum, Perilla frutescens, Calendula officinalis, Salvia splendens, and Sesamum indicum; the many small spots on Chrysanthemum morifolium; and the brown shade on Celosia cristata appeared on the upper surface of the intervein, on the leaf apex area and on the entire upper surface of leaves, respectively. 3. Visual injuries of Capsicum annum(Chunchu), Perilla frutescens, Sesamum indicum(Pungnyun, Kwangsan), and Salvia splendens were developed at 0.4ppm of $SO_2$ gas injuries for 19 varieties of 10 species of plants were investigated within a environmentally controlled growth chamber. Visible injuries were observed when exposing the plants either 0, 0.2, 0.4, 0.7 or 1.5ppm of $SO_2$ gas for 5 days from 9 : 00 to 17 : 00 everyday. The results obtained were as follows: 1. Light brown spots were shown on Raphanus sativus(Chunchu, Taeback, Jinjudaepyung), Brassica campestris(Manchun, Josaengmiho, Seoul, Jeonseung), and Capsicum annum(Searona, Hongsanho, Hongilpum); brown spots on Sesamum indicum(Pungnyun, Kwangsan); reddish brown shades on Cleosia cristata; and black brown spots on Perilla frutescens, Calendula officinalis, Chrysanthemum morifolium, and Salvia splendens, respectively. 2. The spotty injuries induced by SO₂ gas on Raphanus sativus, Callistephus chinensis, Capsicum annum, Perilla frutescens, Calendula officinalis, Salvia splendens, and Sesamum indicum; the many small spots on Chrysanthemum morifolium; and the brown shade on Celosia cristata appeared on the upper surface of the intervein, on the leaf apex area and on the entire upper surface of leaves, respectively. 3. Visual injuries of Capsicum annum(Chunchu), Perilla frutescens, Sesamum indicum(Pungnyun, Kwangsan), and Salvia splendens were developed at 0.4ppm of SO₂ gas fumigation. Brassica campestris(Jeonseung), Capsicum annum(Searona, Hongilpum), and Cleosia cristata, however, showed the injury at 1.5ppm of $SO_2$ gas concentration. 4. Based on the tolerance grade(time when the 1st injury appeared), Raphanus sativus, Perilla frutescens, Sesamum indicum, and Salvia splendens were the most sensitive plants and Chrysanthemum morifolium, Callistephus chinensis, Cleosia cristata, and Calendula officinalis were the plants most tolerant of $SO_2$ gas. gas fumigation. Brassica campestris(Jeonseung), Capsicum annum(Searona, Hongilpum), and Cleosia cristata, however, showed the injury at 1.5ppm of $SO_2$ gas concentration. 4. Based on the tolerance grade(time when the 1st injury appeared), Raphanus sativus, Perilla frutescens, Sesamum indicum, and Salvia splendens were the most sensitive plants and Chrysanthemum morifolium, Callistephus chinensis, Cleosia cristata, and Calendula officinalis were the plants most tolerant of $SO_2$ gas.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.83-94
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• 2010

Chinese fir (Latin name: Cunninghaimia lanceolata) is one of the major commercial coniferous trees. Most of Chinese fir forests are managed in successive rotation sites, which lead productivity to decline. Autotoxicity is the important reason for soil degradation of Chinese fir plantation, especially, phenolic acids are considered as the major allelopathic toxins which induce autotoxicity in Chinese fir rotation stands. We performed here proteomic approach to investigate the response of proteins in Chinese fir leaves to salicylic acid. The tube plantlets of Chinese fir clone were treated with 120 mg/L salicylic acid for 1, 3 and 5th day. 2-DE, coupled with MALDI-TOF-TOF/MS, was used to separate and identify the responsive proteins. We found 12, 7, and 12 candidate protein spots that were up- or down-regulated by at least 2.5 fold after 1, 3, and 5th day of the stress, respectively. Of these protein spots, 16 spots were identified successfully. According to the putative physiological functions, these proteins were categorized into five classes (1) the proteins involved in protein stability and folding, including 26S proteome, Grp78, Hsp70, Hsp90 and PPIase; (2) the protein involved in photosynthesis and respiration, including OEC 33 kDa subunit, GAPDH; (3) the protein related to cell endurance to acid, F-ATPase; (4) the protein related to cytoskeleton, tubulin; (5) the protein related to protein translation: prolyl-tRNA synthetase. These results give new insights into autotoxic substance stress response in Chinese fir leaves and provide preliminary footprints for further studies on the molecular signal mechanisms induced by the stress.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.217-222
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• 1996

A green-house experiment was conducted to know the performance of Chinese cabbage and radish applied with simulated acid rain(SAR) on the leaf and/or soil. The pHs of SAR and normal water were 2.7 and 6.0, respectively. The pHs of SAR and normal water applied on leaf/soil were 6.0/6.0, 6.0/2.7, 2.7/6.0, and 2.7/2.7 and they were applied fifteen times at the two- or three-day intervals with 10mm at a time. Leaf application of SAR caused brown spots in both crops, while no such symptoms were observed in soil application. SAR applied on the leaf or soil increased chlorophyll content significantly in Chinese cabbage, but slightly in radish. Leaf or soil application of SAR did not affect N, P, and K concentrations in both crops. The sulfur content in radish leaf increased by leaf or soil application of SAR, while in the root it increased by soil application only. Yield of Chinese cabbage was not affected by SAR, while both leaf and root yields of radish were significantly reduced by leaf application of SAR compared with soil application.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.130-133
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• 2004

Leaf blight and fruit rot of sweet persimmon (cv. Fuyu) caused by Pestalotia diospyri were observed during the growing season and postharvest such as storage and transport, respectively. Typical symptoms on leaves developed with small brown spots and were later reddish brown colors. In the storage fruit, the white mycelial mats formed between fruit and calyx. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar (PDA). Colony color of the fungus was white at first on PDA. Conidia were ovoid or fusiform, 5 cells, middle 3 cells were olive, upper and lower 2 cells were colorless, and their size were $16{\sim}22\;{\times}\;6{\sim}8\;{\mu}m$. They had were $2{\sim}3$ appendage at basal cell and size $9{\sim}18\;{\mu}m$. Based on the cultural and mycological characteristics and pathogenicity test on host plants and fruits, the fungus was identified as Pestalotia diospyri Syd.&P. Syd. This is the first report on the leaf blight and fruit rot of sweet persimmon caused by Pestalotia diospyri in Korea.