• Research in Plant Disease
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• v.19 no.2
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• pp.95-101
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• 2013

Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is one of the most serious diseases of crucifers world-wide. To establish the efficient screening method for resistant cabbage to Xcc, different inoculation methods, inoculation positions, growth stages of seedlings, and incubation temperatures after inoculation were investigated with the seven cabbage cultivars showing different resistance degrees to the pathogen. Clipping with mouse-tooth forceps was better inoculation method than piercing with 18 pins or cutting with scissors to distinguish the level of resistance and susceptibility. In inoculation using mouth-tooth forceps, clipping the edges of the leaves near veins is more effective than injuring the veins of the leaves directly. In addition, the inoculated plants kept at $22^{\circ}C$ showed more clear resistant and susceptible responses than those kept at 26 or $30^{\circ}C$. On the basis of the results, we suggest that an efficient screening method for resistance of cabbage cultivars to black rot is to clip the edges of the leaves near veins of the four-week-old seedlings with mouth-tooth forceps dipped in a suspension of Xcc at a concentration of $7{\times}10^7$ cfu/ml and incubate the inoculated plants in a growth room at $22^{\circ}C$ with 12-hr light a day.

• Food Science and Preservation
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• v.23 no.2
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• pp.204-210
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• 2016

This study aimed to find an effective preservation method of lotus leaves for the preparation of lotus-leaf Yakju throughout the year. The characteristics of Yakju containing lotus leaves pretreated by blanching, steaming, roasting, and drying were investigated in this study. The chemical properties of Yakju (pH, amino acidity, alcohol content, and volatile acid content) were significantly different for all treatments, except for the total acid content. The polyphenol content ranging from 315.89 to 462.63 ppm (p<0.05) was significantly different depending on pretreatment method L color value for Yakju was not significantly different all treatments, while a value was significantly different in Yakju containing frozen stored leaves after pretreatment. The b value was lowest for the blanching treatment, and was significantly different for all treatments. Among the organic acids present in Yakju, the oxalic, citric, and malic acid contents were significantly different for all treatments. In sensory evaluation, lotus-leaf Yakjus containing fresh leaves and dried leaves were preferred to the others in color and flavor among Yakjus prepared with lotus leaves before cold storage. However, among the Yakjus prepared with lotus leaves after cold storage, that containing blanched leaves was preferred to the others in terms of flavor, taste, and overall acceptability.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.335-345
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• 2020

Tomato grey mould has been one of the destructive fungal diseases during tomato production. Ten mM of menadione sodium bisulfite (MSB) was applied to tomato plants for eco-friendly control of the grey mould. MSB-reduced tomato grey mould in the 3rd true leaves was prolonged at least 7 days prior to the fungal inoculation of two inoculum densities (2 × 10⁴ and 2 × 10⁵ conidia/ml) of Botrytis cinerea. Protection efficacy was significantly higher in the leaves inoculated with the lower disease pressure of conidial suspension compared to the higher one. MSB-pretreatment was not effective to arrest oxalic acid-triggered necrosis on tomato leaves. Plant cell death and hydrogen peroxide accumulation were restricted in necrotic lesions of the B. cinereainoculated leaves by the MSB-pretreatment. Decreased conidia number and germ-tube elongation of B. cinerea were found at 10 h, and mycelial growth was also impeded at 24 h on the MSB-pretreated leaves. MSB-mediated disease suppressions were found in cotyledons and different positions (1st to 5th) of true leaves inoculated with the lower conidial suspension, but only 1st to 3rd true leaves showed decreases in lesion sizes by the higher inoculum density. Increasing MSB-pretreatment times more efficiently decreased the lesion size by the higher disease pressure. MSB led to inducible expressions of defence-related genes SlPR1a, SlPR1b, SlPIN2, SlACO1, SlChi3, and SlChi9 in tomato leaves prior to B. cinerea infection. These results suggest that MSB pretreatment can be a promising alternative to chemical fungicides for environment-friendly management of tomato grey mould.

• Food Science and Preservation
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• v.23 no.7
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• pp.1004-1011
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• 2016

Flavonoids, non-nutrient secondary metabolites of plants, are widely distributed in commonly consumed agro-food resources. Flavonoids include aglycones, and their glycosides are reported to have potential health-promoting compounds. The aim of this study was to investigate flavonoid glycosides in the fruit and leaves of Zizyphus jujuba var. inermis (Bunge) Rehder (jujube). A total of six flavonoids (five flavonols and one chalcone) were identified in jujube fruit and leaves by using ultra-performance liquid chromatography-diode array detector-quadrupole time of flight mass spectrometry along with chemical library and an internal standard. In positive ion mode, six flavonoids were linked to the C- and O-glycosides which were conjugated with sugar moieties based on kaempferol, quercetin, and phloretin aglycones. Total flavonoid contents of leaves (8,356.5 mg/100 g dry weight (DW)) was approximately 900-fold higher than that of fruit (fresh fruit, 13.6 mg/100 g dry DW; sun-dried fruits, 9.2 mg/100 g dry DW). Quercetin 3-O-rutinoside (rutin) and quercetin 3-O-robinobioside were the predominant flavonols in fruit and leaves of jujube. In particular, rutin had the highest content (6,735.2 mg/100 g DW) in leaves, and rutin is a widely reported bioactive compound. Phloretin 3',5'-di-C-glucoside (chalcone type) was detected only in leaves. The leaves of jujube contain a high content of flavonoids and the results of this study indicate that jujube leaves may be a source of bioactive flavonoids.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.147-148
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• 2007

• Natural Product Sciences
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• v.3 no.2
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• pp.106-107
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• 1997

Indole-3-methylethanoate was isolated for the first time form natural source i.e. from the leaves of Camellia sinensis (L.) O. Kuntz and fully characterized by physical and chemical evidence, the biological activity of the compound was studied by wheat coleoptile bioassay which showed growth promoting activity.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1999.05a
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• pp.22-22
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• 1999

• Proceedings of the Korean Society of Tobacco Science Conference
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• 2000.05a
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• pp.27-27
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• 2000

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.31-32
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• 2010

• Journal of the Korean Society of Tobacco Science
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• v.10 no.1
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• pp.11-19
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• 1988

This study was conducted to relate among growth characteristics, quality, and chemical components for flue-cored tobacco. The results are summarized as follows : 1. Starch content in harvested green leaf was correlated negatively with leaf length, leaf width, leaf area, and leaf weight of harvested green leaf, respectively, while positively with total sugar content in cured leaf, and the ratio of leaf length to leaf width of harvested green leaf. 2. Organic matter and total nitrogen contents in the soil were correlated positively with nicotine content in cured leaf, respectively, and total nitrogen in the soil negatively with total sugar content in cured leaf. 3, Amount of fertilizer, application date of MH, priod of harvesting, and yield were correlated positively with nicotine content in cured leaf, respectively , while negatively with total sugar content. Application amount of MH was correlated positively with total sugar content, but negatively with nicotine content in cured leaf. Also amount of compost was correlated negatively with nicotine content in cured leaf. 4. The ratio of total sugar to nicotine (TS/N) per plant was correlated positively with price (Won/kg) and specific leaf area, but negatively with leaf length. leaf width, leaf area, harvested leaves, and leaf weight in cured leaves, respectively. Yield was correlated negatively with TS/N per plant. 5. TS/N of the best quality tobacco per plant was 12.0. Those of the best quality tobacco in each stalk position were 42.1 for first~third leaf, 28.4 for 4th~6th leaf , 23.7 for 7th~9th leaf, 7.7 for l0th~12th leaf , and 7.8 for over 13th leaf from bottom, respectively. 6, When TS/N was 12.0, optimum values of growth characteristics per plant were 100.5 $\pm$ 10.3g for leaf dry weight, 755.1$\pm$53.2cm for leaf length, 294.4$\pm$25.1cm for leaf width, 8, 892$\pm$111cm2 for leaf area, 16.0$\pm$0.6 leaves for harvested leaves, and 7.32$\pm$0.44mg/cm2 for specific leaf area, respectively. 7. When TS/N was 12.0, optimum values of chemical components per plant were 1.92$\pm$0.28% for nicotine content, and 20.4$\pm$ 1.4 % for total sugar content, and that of yield was 238.3$\pm$ 9.8kg/10a.