• The Plant Pathology Journal
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• v.16 no.3
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• pp.130-136
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• 2000

Differences in physiological and biochemical responses between sensitive and tolerant rice cultivars to ozone were investigated to develop reliable indications of early ozone damage. Three Korean local rice cultivars -sen-sitive cultivar Dongjin (DJ), moderately tolerant cultivar Hwayeong (HY) and tolerant cultivar Ilmee (IM) were exposed to ozone at the concentrations of 100 nl $\textrm{l}^{-1}$ or 200 nl $\textrm{l}^{-1}$ , 8 h per day for 10 days in a controlled-environment fumigation chamber. The rice cultivars seemed to be endurable to ozone stress at the concentration of 100 nl $\textrm{l}^{-1}$ which is frequently monitored during the growing season in summer. However, severe damage was induced and differential sensitivity was clearly noted among the rice cultivars at the higher ozone concentration. Activation of the glutathion (GR) -ascorbate peroxidase (APX) cycle was likely to be responsible for protection of rice plants against ozone exposure, relating difference in sensitivity of rice cultivars to ozone. Photosynthetic activity appeared to be one of sensitive responses, for which chlorophyll fluorescence and leaf greenness can together provide a very reliable index, a degree of photosynthetic damages by ozone. Formation of malondialdehyde (MDA) was also considered as an indication that can differentiate cultivars sensitivity to ozone. However, the changes in polyamines and total phenolics were not consistent with exposed ozone concentrations and/or ozone sensitivity of the cultivars. The behavior of polyamines and phenolics in the damaged plants at high ozone levels could be interpreted as an indication of ozone injury rather than activation of additional protection mechanisms scavenging active oxygen species formed by ozone. Several responses triggered by ozone could explain the differential sensitivity of the rice cultivars and be used as reliable indications of relative ozone damage to rice plant.

• Korean Journal of Pharmacognosy
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• v.43 no.1
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• pp.66-71
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• 2012

Cirsium japonicum var. ussuriense is often used in treatment of human disease such as hemorrhage, blood congestion and inflammation. This study was accomplished to evaluate the antioxidant properties of the leaf (CLE) and flower (CFE) extracts of C. japonicum var. ussuriense to protect normal human red blood cells (RBC) and plasma samples against oxidative damage in vitro. CLE and CFE were prepared by extracting with hot water. In red blood cells and plasma, oxidative hemolysis and lipid peroxidation induced by the aqueous peroxyl radical generator [2,2'-azobis (2-amidinopropane) dihydrochloride, AAPH] were significantly suppressed by CLE or CFE in a dose-dependent manner at the same time. CLE and CFE also prevented the depletion of cytosolic antioxidant glutathione (GSH) in RBC. These results suggest that the leaves and flowers of C. japonicum var. ussuriense may have the antioxidant properties.

• The Korea Journal of Herbology
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• v.38 no.4
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• pp.1-9
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• 2023

Objectives : This study aimed to convert into weight the dosages of flower of Daphne canescens and leaf of Phyllostachys nigra var. henonsis, whose daily dosages are likened to an object in 《Treatise on Cold Damage Diseases》. This study also aimed to understand their implications along with the previously studied gypsium and rhubarb. Methods : After reviewing documents, the dosages were converted into weight, confirmed by experiment, and their implications were considered. Results : A chicken-egg-volume of flowers of Daphne canescens is one Ryang(6.5 g) and two handfuls of leaves of Phyllostachys nigra var. henonsis is four Ryang(13 g). Each item was only used once in a decoction. Their dosages were expressed in weight respectively in 《Supplement to the Essential Prescriptions Worth a Thousand Gold》 and 《Bohenggyuljangbuyongyakbubyo》. Gypsium dosage was expressed in weight except in Daecheongryong-tang as chicken-egg-volume(16 Ryang). To liken a dosage to an object is an exception, as in the three cases above; for precision and convenience it is recommended that dosages be expressed in weight, in which case all three items fell into one of eight categories from one Ryang to 16 Ryang. Rhubarb was measured in weight, but only when using the 12-hour leaching method, four Ryang of rhubarb was cut into of 5-6 wide-go-stone-sized pieces and two Ryang into 5-6 go-stone-sized pieces. Conclusions : To liken a dosage to an object is only an exception and lacks precision and convenience; therefore dosages ended up expressed in weight, count, or volume.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.61-71
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• 1968

1. In pot exreriments, the leaf blades of rice plants grown on Akiochi soil were weakened and the leaves dropped noticeably. This phenomenon could be prevented with application of silicate materials such as potassium silicate, Wallastonite and silicate slag (normally used silicate fertilizer in Korea). 2. Grain yield was increased by application of all the silicate materials. The effect of wollastonite was not lower than the effect of silicate slag. 3. Basal application of wollastonite gives a higher effect on the grain yield than top dressing. With higher wollastonite application, the nitrogen effect on the grain yield increases. This increase in nitrogen effect becomes more pronounced when the nitrogen level is higher. 4. Silica content in the plant waas increased by application of silicate materials to the soil. The increase in silica content in the plant was most noticeable with wollastonite. Basal application of wollastonite proved to be more effective than top dressing. Iron and nitrogen content in the plant decreased by application of the silicate materials. 5. The application of the silicate materials to Akiochi soil increases the resistance of rice to leaf blast, neck blast and Helminthosporium leaf spot. Among the silicate materials, wollastonite was most effective. 6. Damage by leaf blast increased proportionally with the nitrogen level, but decreased clearly with increase in wollastonite level. This phenomon was most pronounced for late transplanting time. 7. Damage by Helminthosporium leaf spot was also proportionally reduced by wollastonite application.

• Journal of People, Plants, and Environment
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• v.23 no.4
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• pp.445-453
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• 2020

Background and objective: Calcium chloride (CaCl₂) and sodium chloride (NaCl) are commonly used as a deicing agent in South Korea and penetrate the soil on the roadside, causing damage to plants. This study was conducted to investigate the salinity reduction effect of Pennisetum alopecuroides and the chemical characteristics of soil leachate. Methods: The plants were treated with five different concentrations of CaCl₂ (0, 1, 2, 5, and 10g·L^-1) and were grouped into the Cont., C1, C2, C5, and C10 groups. CaCl₂ of 200 m·L^-1 was sprayed to each plant once every two weeks. The growth of P. alopecuroides (plant height, leaf length, leaf width and the number of leaves) was measured. The level of EC and pH, and exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) in the leachate of soil was monitored. Results: The pH of soil leachate decreased as the CaCl₂ concentration increased, and the EC increased significantly. The content of K⁺ did not change significantly until the concentration of CaCl₂ reached 5 g·L^-1, but the content of Ca²⁺, Na⁺, and Mg²⁺ significantly increased. The plant height, leaf length, and leaf width of P. alopecuroides showed the highest value in CaCl₂ 1 g·L^-1 followed by CaCl₂ 2 g·L^-1 and the control group. Root fresh weight was the highest in CaCl₂ 2 g·L^-1. On the other hand, there was no change in the shoot fresh weight, dry weight and root dry weight, and P. alopecuroides growth inhibition at the concentration of 5 g·L^-1 or higher in the plant height and leaf length. Conclusion: P. alopecuroides is relatively highly salt-tolerant and can improve the salt damaged soil by lowering the content of the salt-based exchangeable K⁺ ions.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.51-57
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• 2008

This study demonstrates a variability in efficacy of mating disruption against the oriental fruit moth, Grapholita molesta, populations infesting apples cultivated in differential environmental conditions. Throughout the growing seasons, trap catches of G. molesta male moths and damaged leaf and fruit were examined to evaluate the efficacy of a commercialized mating disruptor. Treatment of the mating disruptor significantly reduced the trap catches of male moth in treated plot, compared to those of the untreated plot. This reduced trap catches were significantly correlated with leaf and fruit damage. Moreover, the highest host damage occurred in June just after the highest overwintering adult peaks in both plots. The treatment of mating disruptors in Chungsong effectively disrupted the overwintering population in April and May, resulting in no noticeable host damage during the following growing seasons. However, there was a marked difference in host damage between two plots, especially in late seasons. Variation in the efficacy of mating disruption technology in terms of host damage appeared to be related with nearby pheromone-untreated orchards, which may result in the immigration of gravid females.

• Korean journal of applied entomology
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• v.57 no.1
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• pp.33-38
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• 2018

Walnuts are one of the most economically important fruit trees in forestry. In walnut orchards, however, studies examining damage by insect pests are limited. This study was conducted to investigate the rate of damage caused by Conogethes punctiferalis to walnut fruits and by Acrocercops transecta to walnut leaves. In 2017, the change of damage rate (caused by C. punctiferalis) to fruits were investigated in Buyeo. In addition, we counted fruits and leaves damaged by two lepidopteran species in Gimcheon, Buyeo, Yeongdong, and Hwaseong. Damaged fruits steadily increased in abundance with fruit growth in Buyeo, and the highest number of damaged fruits was documented in late summer. The rates of damage caused by C. punctiferalis to fruits in Buyeo, Gimcheon, and Hwaseong were 22.1%, 20.5%, and 11.7%, respectively. Additionally, the rates of damage caused by A. transecta to leaves in seedlings (58.5% on average) were significantly higher than to those in older trees (11.2% on average), irrespective of the study location. In conclusion, this study showed that C. punctiferalis and A. transecta were serious pests affecting walnut fruits and leaves, respectively. Therefore, management methods for these insect pests need to be developed.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1093-1101
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• 2006

In the present study we studied the growth, photosynthetic traits and protective mechanisms against oxidative stress in the primary loaves of cucumber (Cucumis sativus L.) seedlings with or without UV-B treatment. Cucumber seedings were irradiated with UV-B for 10 days in environment-controlled growth chambers. The primary leaves irradiated with UV-B showed reduction in leaf length and decreased biomass production. The reduced biomass production seemed to be due to a negative effect of UV-B radiation on the photosynthetic process. Changes in chemical properties of leaf, such as chi a/b ratio affected photosynthesis. UV-B significantly affected chl b content compared with chi a in the light harvesting complex resulting reduced photosynthetic activity Fv/Fm decreased with an UV-B stress, suggesting that the photosynthetic apparatus, and particularly, PS II was damaged under UV-B stress. Malondialdehyde(MDA) concentration which represents the state of membrane lipid peroxidation Increased significantly under UV-B stress confirming an oxidative stress. UV-B exposure with SA solution(0.1-1.0 mM) can partially ameliorated some of the detrimental effects of UV-B stress. Leaf injuries including loss of chlorophyll and decreased ratio of Fv/Fm were reduced with combined application of UV-B and SA. ABA and JA showed similar mode of action in physiological effects on photosynthetic activities though the levels were lower than those from SA treated plants. Chloroplast ultrastructure was also affected by UV-B exposure. The thickness of leaf tissue components decreased and the number of grana and thylakoids was reduced in chloroplast applied UV-B or SA alone. At combined stress granal and stromal thylakoids were less affected. The leaves under combined stress acquired a significant tolerance to oxidative stress. From these results, it can be suggested that SA may have involved a protective role against UV-B induced oxidative damage.

• Nutrition Research and Practice
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• v.3 no.2
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• pp.114-121
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• 2009

The effect of diet supplemented with red beet (Beta vulgaris L.) leaf on antioxidant status of plasma and tissue was investigated in C57BL/6J mice. The mice were randomly divided into two groups after one-week acclimation, and fed a high fat (20%) and high cholesterol (1%) diet without (control group) or with 8% freeze-dried red beet leaf (RBL group) for 4 weeks. In RBL mice, lipid peroxidation determined as 2-thiobarbituric acid-reactive substances (TBARS value) was significantly reduced in the plasma and selected organs (liver, heart, and kidney). Levels of antioxidants (glutathione and $\beta$-carotene) and the activities of antioxidant enzyme (glutathione peroxidase) in plasma and liver were considerably increased, suggesting that antioxidant defenses were improved by RBL diet. Comet parameters such as tail DNA (%), tail extent moment, olive tail moment and tail length were significantly reduced by 25.1%, 49.4%, 35.4%, and 23.7%, respectively, in plasma lymphocyte DNA of RBL mice compared with control mice, and indicated the increased resistance of lymphocyte DNA to oxidative damage. In addition, the RBL diet controlled body weight together with a significant reduction of fat pad (retroperitoneal, epididymal, inguinal fat, and total fat). Therefore, the present study suggested that the supplementation of 8% red beet leaf in high fat high cholesterol diet could prevent lipid peroxidation and improve antioxidant defense system in the plasma and tissue of C57BL/6J mice.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.1-24
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• 1985

The pinus trees planted by the road in the Seoul -Suwen high-way was surveyed on the damages due to air pollution during April and May in 1984. The results were as follows ; The concentration of SO$_2$was ranged from 0.003 to 0.05ppm, NOx from 0.03 to 0.1ppm and the amount of dust fall, from 10 to 110ton/km$^2$/month. While the concentrations of gaseous pollutants such as SO$_2$and NOx were notsignificantly different in the type of road and with in the distence of 20 meters from the road the dust falls were decreased as remoted from the road. The tissue damages of leaves were determined by the microscopic observation. The higher concentration of dust fall on the leaf, the more severe damage observed in the stomata. The attached dust of the leaves were ranged from 1l to 75mg/g of leaf, and those were significantly incereased as near from road. The sulfur contents of leaves were measured at 0.15g/100g of leaf in the 5 meters located and at 0.064g/100g of leaf in the 20 meters, and the lead contents, 45ug/g of leaf in the 5 meters and 24ug/g in the 15 meters. The appearent damages of plant were very much corelated to the attached dusts of leaves the sulfur contents and the amount of dust fall, and the multiple regression analysis between the damages and factors of air pollution were under taken. As increment of vehicle in future, the air Pollution was predicted and the plant damages were estimated.