• Korean journal of applied entomology
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• v.26 no.4 s.73
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• pp.251-255
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• 1987

This study was conducted to investigate the effects of cultural methods on infection by Rhizoctonia disease(Rhizoctonia solani $K\"{u}hn$) of potato (Solanum tuberosum L.). Two potato cultivars, i.e., Irish Cobbler and Superior were planted in 1984 at the Alpine Experiment Station and 4 cultural methods were used in Combinations or separately. The deeper planting showed the later germination of sprout. The degree of infection on underground stems didn't show any differences between the treatments, but the yield was higher in deeper planting. When seed tubers were planted on April 28 the underground stems showed severely discolourated epidermis comparing to later planting, consequently the yield was low. The glazed chitting tubers produced healthy sprouts comparing to the untreated tubers, consequently the yield was also increased. The density of sclerotia on tuber skin was remarkably increased between 6 to 15days of delayed digging after haulm killing. Underground stems of Irish Cobbler were easily discolourated by the disease, where-as the density of sclerotia was higher on tuberskin of Superior than of Irish Cobbler.

• 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.

• Research in Plant Disease
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• v.8 no.2
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• Research in Plant Disease
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• v.13 no.1
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• pp.1-5
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• 2007

Major diseases of tobacco and farmer's control practices were surveyed in the Kyeongbuk province area from 2005 to 2006. Mosaic caused by potato virus Y and bacterial wilt caused by Ralstonia solanacearum were most severe during the harvest season. Compared with the disease occurrence of ten years ago, the damage by tobacco mosaic virus reduced but bacterial wilt increased. These changes in the disease occurrences may probably be due to releasing the resistant tobacco cultivar to the mosaic virus but susceptible to the bacterial wilt pathogen. More than thirty percentage of the farmers have misused fungicides and also have applied the continuous mono-cropping system for more than ten years, and have chosen the incorrect crops for the rotation.

• Mycobiology
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• v.51 no.3
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• pp.186-194
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• 2023

In July 2021, wilting symptoms were observed in adult and seedling hemp (Cannabis sativa L. cv. Cherry Blossom) plants grown in a greenhouse. As the disease progressed, yellowing and wilting symptoms on the leaves developed, resulting in whole plant death. In seedling plants, typical damping-off symptoms were observed. To identify the pathogen, the roots of diseased plants were sampled, surface sterilized, and cultured on potato dextrose agar (PDA) media. From the culture, 4 different fungal isolates were recovered and purely cultured. Each fungal isolate showed distinct growth shapes and color development on malt extract agar, oatmeal agar, sabouraud dextrose agar, and PDA media. Microscopic observation and molecular identification using ribosomal DNA internal transcribed spacer sequencing identified them as 3 Fusarium spp. and 1 Thielaviopsis paradoxa. Additional sequencing of elongation factor 1-alpha and b-tubulin regions of 3 Fusarium spp. revealed that 2 of them are Fusarium solani, and the other one is Fusarium proliferatum. To examine which isolate can act as a causal agent of wilt disease of hemp, each isolate was tested for their pathogenicity. In the pathogenicity test, F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3, but not T. paradoxa AMCF4, were able to cause wilting disease in hemp seedlings. Therefore, we report that F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3 as causal agents of Fusarium wilt of hemp plants. To our knowledge, this is the first report of the wilt disease of C. sativa L. caused by Fusarium spp. in Korea.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.264-274
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• 2003

Many potato genetic resources have been collected and improved for their diverse traits over the years using breeding program in KPGR. To select potential varieties for table and processing in Korea, 58 elite potato breeding lines and several 'Valley' varieties were cultivated and harvested at Korea Alpine area in 2001. The cultivated lines and varieties were evaluated using their cultural adaptability in the environment and tuber characteristics, such as the depth of tuber eye, tuber shape, skin color, flesh color, scab resistance, yield, and the resistance of hollow heart and internal brown spot disease. Additionally, in the selection of potential processing varieties, reducing sugar content (sum of glucose and fructose concentration) of tubers is critically considered, because it mainly influence on the chip color of processing potato tuber. For table stock varieties with white skin color, 'Early Valley', 'Summer Valley', 'Winter Valley', and 'Taebok Valley' were selected. In the aspect of diverse potato tuber color, several varieties were selected such as 'Golden Valley' for its yellow fresh and skin color, 'Gogu Valley', 'Juice Valley', and 'Rose Valley' for their red skin color, and 'Purple Valley' for its purple skin. Compared with world wide known processing cultivar 'Atlantic', 24 lines (or varieties) were selected for the potential potato processing industry due to their low reducing sugar contents (below 0.3％), high yield (above 4.0 ton/ha), and unique chip colors. Selected white chipping varieties were 'Taedong Valley', 'Kangshim Valley', and 'Kangwon Valley', which have 0.23％, 0.27％, and 0.29％ of reducing sugar contents, respectively. 'Bora Valley', having deep purple color in both skin and fresh, was selected for purple chip variety and has 0.26％ of reducing sugar content. Light yellow chip varieties (lines) were 'Rose Valley' and Valley 54, having 0.19％ and 0.269％ of reducing sugar content, respectively. For French frying potatoes, 'Stick Valley' of 0.22％ and Valley 72 of 0.151％ in reducing sugars were selected. All of these selected lines and 'Valley' varieties can be used as parents to improve potato genetic resources and to develop better varieties with unique traits and colors.

• 한국약용작물학회:학술대회논문집
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• 2009.05a
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• pp.293-294
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• 2009

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.43.2-43
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• 1999

• Research in Plant Disease
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• v.17 no.2
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• pp.232-234
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• 2011

During survey of postharvest diseases of vegetables in the middle region of Korea in 2003, 2004 and 2005, new disease symptoms showing watery rot and soft rot were observed. In this study, the disease causal agents were identified as Geotrichum candidum, and their host range and pathogenicity were investigated. G. candidum isolated had wide host range and strong pathogenicity against carrot, cucumber, tomato and pumpkin. The disease occurrence on several vegetables that G. candidum can be a serious threat to stable production of fresh vegetable.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.491-495
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• 1998

A fungal disease of the cultivated mushroom, Ganoderma lucidum, caused by Xylogone sphaerospora was epidemic throughout all cultivation areas in Korea which caused a lot of yield losses in the mushroom production. For controlling the disease, the screening of effective fungicides against the pathogenic fungus were conducted. Thirty seven commercially available fungicides were tested for their inhibitory activities on potato dextrose agar media supplemented with these fungicides at various concentrations. Twenty one fungicides significantly inhibited mycelial growth of the pathogen, Xylogone sphaerospora, but 16 fungicides had no inhibitory effect. Among these 21 fungicides, 17 fungicides also inhibited mycelial growth of Ganoderma lucidum as well, but imazalil, procymidone, triforine, and vinclozolin had no inhibitory effects. However, vinclozolin showed no inhibitory effect on mycelial growth of the mushroom even at the concentration of 50 $\mu\textrm{g}$/ml vinclozolin solution for 2 hours, and then the pathogen was inoculated. After two month-cultivation of the mushroom, over 90% of logs treated with vinclozolin without pathogen inoculation produced fruiting bodies. However, fruiting bodies were not produced form the logs inoculated with the pathogen, but not treated with vinclozolin. Fifty seven percent of logs. which were pre-treated with vinclozolin and then inoculated with the pathogen produced fruiting bodies. Based on the results, vinclozolin is effective for the control of yellow disease of the Ganoderma lucidum caused by Xylogone sphaerospora.