• Research in Plant Disease
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• v.10 no.1
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• pp.13-16
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• 2004

A basal stem rot disease of potato (Solanum tubersum) grown on hydroponic system in greenhouse was found in Jeju-city, Jeju Province of Korea in January 2001. The symptoms occurred on basel stem and root, and than plants eventually were died. The casual fungus isolate from basal stem rot symptom and identified to be Pythium myriotylum on the basis of mycological characteristics; Main hyphae wide were 8.4 ${\mu}{\textrm}{m}$ in size. Oogonia were spherical, smooth, mostly terminal in shape and 26.4∼31.2 ${\mu}{\textrm}{m}$ in size. Antheridia were 9.6∼14,4${\times}$4.8-9.6 ${\mu}{\textrm}{m}$ in size. Oospores were spherical, smooth, aplerotic in shape and 21.6∼26.4 ${\mu}{\textrm}{m}$ in size. This is the first report on the basal stem rot of potato caused by P. myriotylum in Korea.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.377-382
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• 2012

This study investigated the occurrence of sweet potato whitefly, Bemisia tabaci affecting cucumber, eggplant and red pepper, as well as sweet potato species, and its response to insecticides in Gyeonggi province from 2010 to 2011. Sweet potato whitefly is widespread throughout the southern part of Gyeonggi province. Most regional populations of B. tabaci belong to biotype Q having been reported in the south Korea since 2005, but in Goyang mixed populations of two biotypes (B and Q) were found. Survey results of Tomato Yellow Leaf Curl Virus (TYLCV) disease that was vectored by B. tabaci indicated that this virus disease was not spread throughout the Gyeonggi province. Biotype Q of B. tabaci was found to be resistant to neonicotinoid insecticides, whereas biotype B was highly susceptible to them.

• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.445-452
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• 1996

• Journal of Plant Biotechnology
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• v.41 no.2
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• pp.65-72
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• 2014

Plant cells from which the cell walls have been enzymatically or mechanically removed are called protoplasts. The protoplasts are theoretically totipotent and can be used as sources of somatic cell fusion in practical breeding programs. Wild Solanum species have often been used as sources of important agricultural traits including diverse disease resistance. However, they cannot often be directly applied to breeding programs due to their sexual incompatibility with S. tuberosum. Somatic hybridization via protoplast fusion is one of the ideal methods to overcome this limitation and to introgress certain traits into S. tuberosum. This technique has still widely been used in potato since the first fusion was reported in 1970s. Therefore, this review highlights general perspectives of protoplast fusion and discusses the application of protoplast fusion in potato breeding.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.163-168
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• 1994

Erwinia rhapontici causes soft-rot disease in a number of plants such as rhubarb, onion, hyacinth and garlic. Pectate lyase (Pel) depolymerizes pectin and other polygalacturonates, which is though to play a role in bacterial invasion of plants. Pel activity was not detected in E. rhapontici cultured in a minimal salts medium containing glycerol, polygalacturonate, or citrus pectin as a carbon source. However, when sterilized potato tuber and Chinese cabbage slices were added to minimal salts polygalacturonate (0.5%) medium, E. rhapontici produced pectate lyase enzyme. Also Pel activity was consistently detected from macerated potato tubers, Chinese cabbage leaves, lettuce leaves and celery petioles tissue. Pel in the extract of macerated Chinese cabbage caused by E. rhapontici strain 1, resulted in electrolyte loss, tissue maceration and cell death of potato tuber tissue. These results indicate that E. rhapontici produces pectate lyase only in the presence of non-diffusible plant components, and that this enzyme probably contributes to its pathogenicity.

• Korean journal of applied entomology
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• v.2
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• pp.12-15
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• 1963

1. The trials were planned to test seven different fungicides for the control of Early blight of potato during the period of 1962 and 1963. 2. All of fungicides tested in the trials were considerably effective to control the disease, as the result of 4 applications which was done in one week intervals from early of June in 1963. All treatments were effective enough to make significant differences from the untreated. Especially, Dithyane M45, Difolatan and Dithane M22 showed satisfactory control even though no significant differences were obtained among them. Besides the three treatments, Bordeaux Mixture were relatively effective.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.186-193
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• 1980

The causal organism of Phytophthora disease on Panax ginseng Meyer in Korea was isolated and identified as Phytophthora cactorum. It's pathogenicity, etiology, and possible control measures were investigated. Disease symptoms on various parts of ginseng plants were also described The fungus caused seedling and mature plant blight and root rot. Oospores were easily formed on potato dextrose agar and corn meal agar. Oospores, however, were not formed in the diseased root tissues but did in the in footed shoots such as leaves, petioles, and stems and in the inoculated berries.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.153-159
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• 1998

The vein necrotic strain of Potato Virus Y (PVY - VN) and black shank (Phyto-phthora parasitica var. nicotianae) are the two major diseases causing severe damages especially in burley tobacco (N. tabacum L.) area in Korea. A new tobacco variety, KB 111, resistant to PVY and black shank disease, was developed by Korea Ginseng & Tobacco Research Institute in 1997. It is a male sterile(MS) F$_1$ hybrid of the cross between MS TC 613 and KB 108. KB 111 was compared to Burley 21 on the agronomic characteristics and disease resistances in performance tests: It possessed upright growth habit and flowered two days later than Burley 21. It was resistant to both PVY and black shank and yielded about 3% more cured leaf than Burley 21, but other characteristics are very simiar to those of Burley 21. The chemical composition and physical properties of the cured leaf of KB 111 were as much acceptable as those of Burley 21 while it produced average yield of good quality leaf and appeared to resistant to PVY and black shank disease on regional farm test in 1998.

• Research in Plant Disease
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• v.29 no.4
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• pp.399-404
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• 2023

Agricultural activities and the number of farms in the subarctic regions have been increasing annually after the coronavirus disease 2019 pandemic to achieve food self-sufficiency. Potatoes are vulnerable to soft rot bacteria at all stages of production, storage, and transportation. A novel bacterium, Pseudomonas sp. N3-W, isolated from Alaska tundra soil, grows at 5-25℃ and produces extracellular protease(s). N3-W caused necrotic spots (hypersensitivity) in hot pepper leaves and soft rot disease (pathogenicity) in potato tubers. The psychrotolerant N3-W caused significant soft rot symptoms on potatoes at a broad temperature range (5℃, 15℃, and 25℃). In contrast, mesophilic Pectobacterium carotovorum KACC 16999 induced severe rotting symptoms in potatoes at their optimal growth temperature of 15℃ and 25℃. However, it barely produced symptoms at 5℃, which is the appropriate storage and transportation temperature for potatoes. The results of pathogenicity testing imply that psychrotolerant soft rot pathogens from polar regions may cause severe soft rot not only during the crop growing season but also during storage and transportation. Our study indicates the possibility of new plant pathogen emergence and transmission due to the expansion of crop cultivation areas caused by permafrost thawing in response to recent polar warming.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.116.2-117
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• 2003

Late blight, caused by Phytophthora infestans, is one of the most destructive disease on potato and tomato cultivation. To analysis genetic diversity P. infeatans isolates were collected from potato and tomato fields in Korea. These pathogens contained both Al and A2 mating type with metalaxyl-resistant and sensitive isolates. Polymorphisms showed base on RAPD (Random Amplified Polymorphic DNA) in both potato and tomato isolates of P. infestans. Cluster analysis showed high level genetic variation in potato isolates of P. infestans than tomato isolates. P. infestans isolates were observed genetic diversity among them but not grouped among isolates related mating type and metalaxyl response. These results exhibited that P. infestans isolates showing genetic difference among them were distributed in Korea.