• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.177-184
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• 2007

Bioactive substances, antioxidant activities and tyrosinase inhibitory activities of seed extracts were evaluated to discover new functional materials, using 13 edible or medicinal plants. Total polyphenol and flavonoid contents were highest in Taxus cuspidata, with $57.51mg{\cdot}g^{-1}\;and\;7.98mg{\cdot}g^{-1}$, respectively. Seed extract of Vitis coignetiae${\times}$Vitis labruscana($RC_{30}=0.030mg{\cdot}ml^{-1}$) was found to be the most effective in DPPH radical scavenging test, and the highest ABTS radical scavenging activity was shown in Diospyros lotus($RC_{30}=0.044mg{\cdot}ml^{-1}$). Inhibitory effects on peroxidation of linoleic acid determined by ferric thiocyanate (FTC) method were similar to BHT in Diospyros kaki, Diospyros lotus, Magnolia officinalis, Styrax obassia, Vitis coignetiae, Vitis coignetiae${\times}$Vistis labruscana, Zizyphus jujuba, Zizyphus jujuba var. inermis. For the inhibition against mushroom tyrosinase, Diospyros kaki, Diospyros lotus, Poncirus tritoliata, Prunus serrulata var. spomtanea, Zizyphus jujuba and Zizyphus jujuba var. inermis exhibited inhibitory activity, and especially Diospyros lotus showed the strongest inhibition.

• Research in Plant Disease
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• v.15 no.3
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• pp.259-261
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• 2009

Sclerotinia shoot rot of Grapevine(Vitis labruscana) occurred at Gapyeong and Yeongwol area from 2003 to 2005. Infected plants showed shoot blight at the one-year-old fruit bearing branches. The first visible symptom noticed was wilting and blighting of the branches. The obvious and typical initial symptom is the presence of a cottony, white, dense mat of mycelial growth on the surface of the diseased lesions. The base or stem of the infected young shoots develop a pale brown rotted area, which girdled and killed shoots. In advanced stages of the disease, stems and branches became bleached and eventually died. The isolates collected from diseased grapevine stem were identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The pathogenicity test revealed that Vitis vinifera(cultivar: Kyoho) was stronger than V. labruscana(cultivar: Campbell early) to the pathogen. This is the first report on sclerotinia shoot rot of grapevine in Korea.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.607-612
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• 2011

The occurrence of grape berry shattering and decay is influenced by the pre- and/or postharvest infection of decay organisms and pest. Postharvest infection is associated with physical damage due to rough handling. To control quality loss during storage of table grapes, the effects of slow releasing $SO^2$ pad on storability of 'Rosario Bianco' (Vitis vinifera) and 'Campbell Early' (Vitis labruscana) grapes were examined, respectively. The $SO^2$ concentration in package of tables grapes reached to at about 40 $ug{\cdot}L^{-1}$ after 40 days of treatment and remained more than 80 days above 15 $ug{\cdot}L^{-1}$. Decay was found in untreated 'Rosario Bianco' and 'Campbell Early' grapes at each for 44 and 85 days after storage, but not in $SO^2$ pad treated grapes. The storage potential of grape berries at $0^{\circ}C$ increased 2~3 times depending on cultivar by $SO^2$ pad treatment. The application of $SO^2$ pad is confirmed to be effective on the increase of market potential with minimizing quality loss such as berry shattering and decay.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.104-113
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• 1991

This experiment was conducted to find the effect of calcium salts on the inhibition of 'Campbell Early' grape(Vitis labruscana B.) berry absicission induced by ethephon. Ethylene evolution, berry abscission rate, and fruit quality were examined. Several mineral contents were determinded in the berries and morphological changes of cells in abscission zone were also studied. 1. Calcium acetate($4.4-8.8g/{\ell}$) and calcium hydroxide($2.2-8.8g/{\ell}$) completely inhibited berry abscission when applied with ethephon 1,000 ppm while calcium chloride was less effective. 2. Ethylene evolution in the berries treated with ethephon alone reached to maximum peak one day after application. However, that peak in the treatment of ethephon with calcium acetate occurred 3 hours after application. 3. No decrease of ethylene production capacity was observed in the ethephon solution even when held up to 36 hours after preparation but the effect on berry abscission was significantly reduced. In contrast, ethylene production of the solution prepared with calcium acetate was greatly decreased along with the increase of holding time. The effect of calcium acetate in aged solution on the inhibition of berry abscission was not altered. 4. There were no differences in mineral contents such as Ca, Mg, and K between the berries sprayed with ethephon 500 ppm or not. Additional calcium accumulation was not found in the skin, flesh, and petiole of clusters sprayed with 3 kinds of calcium salts (1.5 g net Ca per liter) respectively when analyzed 2 weeks before maturity. 5. Ethephon (1,000 ppm) alone induced the development of abscission layer in petiole but those applied with calcium acetate (0.05 M) did not develop any distinct abscission layer 3days after treatment.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.115-122
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• 2003

This experiment was conducted to find the effect of a non-purine cytokinin, thidiazuron(TDZ), on the increase of berry size and fruit quality in 'Kyoho' grapes. For the comparison, the effect of forchlorfenuron(CPPU) was also examined The number of shot berries per cluster was significantly increased by the application of TDZ at 5 days after calyptra fall, resulting in the increase of cluster weight but no increase of each berry weight. The increase of berry weight was found when TDZ was applied at 10 to 15 days after calyptra fall. Gibberellin(GA $25mg{\cdot}L^{-1}$) was also effective on the increase of berry weight and the combined application of GA and TDZ further increased the berry weight. TDZ showed stronger effect on the increase of berry weight than CPPU at the same concentration. Berry ripening was more delayed at higher concentration of TDZ but no chemical injury was observed even at $20mg{\cdot}L^{-1}$. Results indicated that TDZ was effective on the quality improvement through berry weight increase and the recommended concentration TDZ for 'Kyoho' grapes was 5 to $10mg{\cdot}L^{-1}$.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.121-124
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• 2003

Optimal extraction condition and free radical scavenging effect of ethanol extracts of Olympia grape (Vitis labruscana L.) seeds and skins were determined. Extraction yield of grape seeds increased with increasing extraction temperature increased, but was not affected by ethanol concentration in grape skins. Highest extraction yields obtained with 100% ethanol concentration at $78^{\circ}C$ were 36 and 49.5% in seeds and skins, respectively. Ethanol extract of grape seeds obtained at $78^{\circ}C$ showed stronger $RC_{50}\;(409.7\;{\mu}g/mL)$ than that of grape skins. Among organic solvent fractions, ethylacetate fraction obtained from ethanol extract of grape seed showed the strongest $RC_{50}\;(136.7\;{\mu}g/mL)$. Overall, ethanol extracts of grape seeds and their organic fractions showed significantly stronger free radical scavenging effect than those of skin extracts.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.1
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• pp.1-9
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• 2017

Recently, it is increasing the grape farm which is converted from paddy field to orchard. These soil which are poor drainage extremely also can be damaged a lot by excessive water or flooding during heavy rain season on summer. Therefore the aim of this study was carried out to measure the changes of soil water potential and to compare the growth responses of 'Jinok' (Vitis spp.) and 'Campbell Early' (V. labruscana) grapes under three drainage systems (control, conventional drainage, and under drainage). After heavy rain, soil water potential holding times above -15 kpa applied water excessive were 352, 348 and 180 hours in control, conventional, and under drainage systems, respectively. The clay content of the under drainage system was lower than the other systems about 8-12%. The crop water stress index was lowest in the under drainage and highest in the control. Also, photosynthetic rate has showed the opposite result with crop water stress index. It was significant differences between the treatments but, the value has not shown significantly different between the varieties. In addition, leaf area and the trunk growth rate was more effective in under drainage than in the control and conventional drainage.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.973-981
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• 2022

'Shine Muscat' (Vitis labruscana Bailey x Vitis vinifera L.) grapes recently have been greatly favored in Korea, and as of 2022, account for 38.6% of the total grape market in Korea. However, there is a lack of research on post-harvest quality control appropriate to the unique characteristics of 'Shine Muscat'. In order to continuously increase domestic demand and exports in the future, it is essential to establish proper postharvest techniques. Essential oils have remarkable potential as biologically active and environmentally friendly antiseptics for the fruit industry. The objective of this study is to evaluate the effects of essential oils and aroma constituent treatment on fruit quality attributes of 'Shine Muscat' grapes in order to extend fruit quality during a simulated export period. A cluster of 'Shine Muscat' grapes was placed in a newly developed paper box container, and treated with rosemary essential oil, thyme essential oil, and linalool, along with an untreated control. The results showed no significant effect on fruit quality indices, such as cluster weight loss, berry firmness, soluble solids content, titratable acidity, sugar acid ratio, and color change, but showed a positive effect on the alleviation of berry shatter compared to the untreated control. In addition, rosemary oil treatment reduced the proportion of unhealthy berries. Therefore, the results indicated that the newly developed packaging container along with certain essential oil treatment could be applied as a promising packaging material for table grape export.

• Food Science and Preservation
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• v.7 no.3
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• pp.241-244
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• 2000

Grapes(Vitis labruscana B) were fumigated with acetic acid at 20mg/liter to reduce storage decay and packaged with polyethylene film(0.03mm), then stored for 90 days at 2$^{\circ}C$. Modified atmosphere packaging reduced slightly weight loss and soluble solids content during storage. Acetic acid fumigation decreased effectively berry shattering and achieved remarkable control of rotting for storage. Two grape cultivars, 'Campbell Early' and 'Sheridan', fumigated with acetic acid had only 0.7~2.9 berries rot compared with 8.3~27.6 berries rot of cluster for grapes that were not fumigated.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.141-146
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• 2000

Glycosidase activities were tested from the grape berries, Vitis labruscana B. Takasumi. Among various glycosidases, $\alpha$-D-galactosidase was found to be the most active in the flesh and other glycosidases were considerably active in the order of the following: $\alpha$-D-mannosidase>$\alpha$-D-glucosidase>$\beta$-D-glucosidase>$\beta$-D-galactosidase. In the seeds, $\alpha$-D-glucosidase activity was the highest and other glycosidases such as $\alpha$-D-galactosidase, $\beta$-D-glucosidase, and $\beta$-D-galactosidase were still significantly active. The $\alpha$-D-galactosidase in the grape flesh was purified over 83-folds through salting-out with $(NH_4)_2SO_4$ and a series of chromatographies employing Sephadex G-50, Octyl-Sepharose, Q-Sepha- rose, and Biogel P-100. The enzyme was a monomer of 45 kDs as determined through SDS-PAGE and Sephacryl S-200 chromatography. The purified enzyme showed a preference of $\alpha$-D-galactose to $\beta$-D-galactose as a substrate about 5.4 times. Sulfhydryl specific reagents such as N-ethylmaleimide and iodoacetamide significantly inhibited the enzyme activity to the extents of 48 and 52% of its initial activity, respectively. The optimumpH range of $\alpha$-D-galactosidase was around 6.5-7.0. The enzyme activity increased by 46% in the presence of 1mM $Fe^{2+}$.