• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.3
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• pp.185-191
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• 2005

An accurate prediction of dormancy release and bud burst in temperate zone fruit trees is indispensable for farmers to plan heating time under partially controlled environments as well as to reduce the risk of frost damage in open fields. A thermal time-based two-step phenological model that originated in Italy was applied to two important grapevine cultivars in Korea for predicting bud-burst dates. The model consists of two sequential periods: a rest period described by chilling requirement and a forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units (chill days in negative sign) until a pre-determined chilling requirement for rest release is met. After the projected rest release date, it adds daily heat units (anti-chill days in positive sign) to the chilling requirement. The date when the sum reaches zero isregarded as the bud-burst in the model. Controlled environment experiments using field sampled twigs of 'Campbell Early' and 'Kyoho' cultivars were carried out in the vineyard at the National Horticultural Research Institute (NHRI) in Suwon during 2004-2005 to derive the model parameters: threshold temperature for chilling and chilling requirement for breaking dormancy. The model adjusted with the selected parameters was applied to the 1994-2004 daily temperature data obtained from the automated weather station in the NHRI vineyard to estimate bud burst dates of two cultivars and the results were compared with the observed data. The model showed a consistently good performance in predicting the bud burst of 'Campbell Early' and 'Kyoho' cultivars with 2.6 and 2.5 days of root mean squared error, respectively.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.308-314
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• 2011

Efficient transformation and regeneration methods are a priority for successful application of genetic engineering to vegetative propagated plants such as grape. In this study, methods for Agrobacterium tumefaciens-mediated transformation and plant regeneration of grapevine (Vitis vinifera) were evaluated. Tamnara, Heukgoosul, Heukbosek, Rizamat were co-cultivated with Agrobacterium strains, LBA4404 containing the vector pBI121 carrying with CaMV 35S promoter, GUS gene as reporter gene and resistance to kanamycin as selective agent. Seven percent of the maximum regeneration frequency was obtained from co-cultivated with explants from Rizamat with LBA4404 strain on selection medium with kanamycin. The addition of acetosyringone, 200 ${\mu}m$ in virulence induction step was a key factor for successful GUS reporter gene expression in grapevine transformation. Transgenic plants showed resistance to kanamycin and the GUS positive response in leaf ($T_0$) stem ($T_0$) and petiole ($T_0$).

• Research in Plant Disease
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• v.12 no.3
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• pp.267-271
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• 2006

Botrytis cinerea Pers. was found to be highly virulent to the grapevine plant, especially in greenhouse condition. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. Of the 83 isolates of Pseudomonas spp., a bacterial strain P84, isolated from tomato rhizosphere, was shown to suppress a wide range of phytopathogenic fungi in vitro. The isolate was identified as Pseudomonas putida on the basis of its bacteriological and genetic characteristics. The P. putida P84 strain carry the phlD gene for 2,4-diacetylphloroglucinol biosynthesis and may produce the antibiotics as an antagonistic mechanism involved in biocontrol. The antagonistic activity of the bacterium has a promising implication for its use as a biocontrol agent to control grapevine gray mold.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.179-190
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• 2023

Grapevine downy mildew, caused by Plasmopara viticola, significantly damages vineyards and is one of the most devastating diseases affecting cultivated grapes worldwide. In this study, we characterized the phenotypic and molecular traits of 11 P. viticola isolates from four grape-growing regions in South Korea. Additionally, we investigated the diversity of pathogenicity among these isolates and conducted an assay to evaluate the response of grape cultivars to P. viticola infection. Lemon-shaped sporangia were identified in the collected isolates, which released zoospores into the suspension at room temperature. Within a few hours of inoculation, the zoospores developed germ tubes. We tested 11 P. viticola isolates for pathogenicity in 845 grape cultivars to screen for grape host resistance to downy mildew infection. Among the tested isolates, JN-9 showed the highest virulence. Grape cultivars displayed varying phenotypic reactions to P. viticola infection: approximately 7% were highly susceptible, 41% were susceptible, 20% were moderately susceptible, 8% were resistant, and 24% exhibited extreme resistance. Phylogenetic analysis based on four genomic regions (internal transcribed spacer 1 [ITS1], actin, beta-tubulin, and cytochrome c oxidase II) revealed a close evolutionary relationship among all the Korean isolates, forming a single monophyletic lineage. Notably, these isolates showed greater similarity to European isolates than to American isolates. This comprehensive study contributes to a deeper understanding of the identity and behavior of P. viticola, which is crucial for developing effective resistance strategies against this pathogen in grape cultivars cultivated in South Korea.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.60.1-60
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• 2000

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.90-90
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• 2002

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.186.4-186
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• 2003

No Abstract, See Full Text

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.143.1-143
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• 2003

Hop stunt viroid(HSVd) is a plant pathogen which infect a number of hosts such as grapevine, Citrus and Prunus plants. Sequence variants of HSVd have been divided into three types(i. grapevine and hop, ii. citrus, iii. plum, peach, apricot and almond). Purified RNAs from plum trees were used for the synthesis of cDNA with reverse transcription and amplified by polymerase chain reaction. Cloned cDNAs were sequenced and two different consensus sequence variants were detected. A neighbor-joining analysis was carried out on the sequence variants together with 62 previously described variants of HSVd from hop, plum and other species. Sequence variants from plum trees cultivated in Korea were clustered in HSVd-plum subtype and not in HSVd-hop subtype which were two Korean isolates belongs. These relationship between sequence variants from plum and two Korean isolates in HSVd-hop type supports the other origin for hop stunt disease.

• The Plant Pathology Journal
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• v.16 no.5
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• pp.290-293
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• 2000

The main grape producing regions in Korea were surveyed for the occurrence and relative incidence of crown gall disease on grapevine. The results of the survey showed that the disease tended to affect tetraploid cultivars, which produce a large and sweet fruit but are very weak to cold weather. Incidence of crown gall disease was high on the tetraploid cultivars, Kyoho (Gerbong), Daebong, and Black Olympia while it was low on the diploid cultivars, Cambell Early and Sheridan. The disease incidence was very high on Anseong, Cheonan, and Chincheon, where the major growing areas of tetraploid cultivars and grapevines were burried in the winter to protect from freeze injury, whereas it was low in Yungdong, Kimcheon, and Nonsan. Crown gall disease did not increased with grapevine age on both Cambell Early and Kyoho. It remained low in Cambell Early, but high for all ages on Kyoho, Galls were found on the crown region and mid part of the trunk, but more galls were on small branches and canes on Kyoho grapevines. More than one third of ZKyoho grapevines inspected had galls on multiple locations on grapevines. On Kyoho, 56.3% of the galls covered more than 50% of the crown gall disease affects severely on the cultivar.

• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.529-541
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• 2011

Bordeaux mixture made with each grade of lime and copper sulfate was tested general property and disease control value. Bordeaux mixture was made by composition of each grade of lime (95%, 80%) with each grade of copper sulfate(98.5%, 95%). Phytotoxicity was evaluated to Bordeaux mixture made with each grade of lime and copper sulfate, and then low grade copper sulfate (95%) was more severely in the grapevine leaf. Bordeaux mixture, made with each grade lime and copper sulfate, were tried to evaluate control effects of downy mildew in field. As a result, Bordeaux mixture (95% of lime and 98.5% of copper sulfate, 6-6) applied 5 times at late in June was showed more effective disease control value than any other trials of Bordeaux mixture. There was no difference in nutrient status of petiole each treatment. But fruit characteristics were shown more slightly improved quality.