• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.181-192
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• 2010

Water erosion is progressing in the Loess Plateau, especially in gullies, and the sediment runoff to the Yellow River amounts to 975 million tons every year. Natural factors for water erosion include climate, soil, geological feature, terrain and vegetation. Many development projects due to the increasing population reduced the forest coverage ratio to 10%, and 200 million people in the downstream area are suffering from the damage during intense rainfall. Accordingly, the Chinese government is continuously trying to efficiently prevent the erosion by establishing measures for water erosion, including fish-scale pits, terrace technique, and check dams.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.155-155
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• 2005

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.156-156
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• 2005

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.344-350
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• 2011

In this study, LVLs of radiata pine were fabricated with non-preservative treated veneers, CuAz treated veneers, and ACQ treated veneers, using aqueous vinyl urethane adhesive and phenol modified resorcinol resin adhesive. Then density gradient, bonding strength, bending properties and decay resistance of LVLs were evaluated. As results, the cone-shaped and higher density gradient pattern was found in layer close to glueline. After cyclic water boiled test, the LVL bonded with aqueous vinyl urethane resin adhesive was delaminated in all layers or partly delaminated including check, chasm in glueline layer. In the case of LVL bonded with phenol modified resorcinol resin adhesive, despite slight cupping due to great glueline stress and vertical check between glueline layers, it was observed that the bonding strength to delamination was higher, owing to most absence of delamination through overall glueline. On the other hand, in the decay test, mass loss by brown rot fungi was greater than white rot fungi in LVL bonded with aqueous vinyl urethane resin adhesive. However, in LVL bonded with phenol modified resorcinol resin adhesive, the mass loss by brown rot fungi was slight and non-preservative treated LVL was low. The mass loss of preservative-treated LVL was 0 (zero), showing the high decay resistance effect.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.380-388
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• 2019

The studies regarding soil bacterial community and correlation analysis of wild-simulated ginseng cultivation area are insufficient. The purpose of this study was to investigate the correlation between soil bacterial community and growth characteristics of wild-simulated ginseng for selection of suitable cultivation area. The bacterial community was investigated by high throughput sequencing technique (Illumina platform). The correlation coefficient between soil bacterial community and growth characteristics were analyzed using Spearman's rank correlation. The soil bacterial community from soil samples of 8 different wild-simulated ginseng cultivated area exhibited two distinct clusters, cluster 1 and cluster 2. The relative abundance of Proteobacteria (35.4%) and Alphaproteobacteria(24.4%) was observed to be highest in all soil samples. The lower soil pH and higher abundance of Acidobacteria resulted in increased growth of wild-simulated ginseng. Additionally, abundance of Acidobacteriia (class) and Koribacteraceae (family) demonstrated significant positive correlation with fresh weight of wild-simulated ginseng. The results of this study clearly state the correlation between growth characteristic and soil bacterial community of wild-simulated ginseng cultivation area, thereby offering effective insight into selection of suitable cultivation area of wild-simulated ginseng.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.53-57
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• 2009

Biological Characteristics of Lycorma delicatula and insecticidal activity of some insecticides against nymphs of L. delicatula was investigated. Nymph of L. delicatula had 4 instars, and color of body was black. There were white spots on the body of 1st-3rd nymph. Upper body became red at 4th nymph. Adult forewings were brownish, and had black spots. Color of hind wing were red. The egg mass was covered with a yellowish brown secretion. The adult of L. delicatula emerged once a year. Among test insecticides, deltamethrin 1% EC and fenitrothion 50% EC showed very quick and strong insecticidal activity against the 2nd-3rd nymphs of L. delicatula. Imidacloprid 4% SL and clothianidin 8% SC showed 100% insecticidal activity at 24h after treatment. Thiacoprid 10% SC revealed the weakest insecticidal activity among the insecticides tested.

• Journal of Plant Biotechnology
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• v.47 no.3
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• pp.254-259
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• 2020

We studied the antioxidative and immunoregulatory properties of 70% ethanol extracts from the leaves, branches, and fruit of 13 species of the Rhamnaceae collected during the bearing season (Berchemia berchemiifolia, Berchemia floribunda, Hovenia dulcis, Paliurus ramosissimus, Rhamnella franguloides, Rhamnus crenata, Rhamnus davurica, Rhamnus koraiensis, Rhamnus parvifolia, Rhamnus ussuriensis, Rhamnus yoshinoi, Sageretia thea, and Ziziphus ujube). Total phenolic and flavonoid content values were determined using calibration curves of gallic acid and rutin, respectively. ABTS and DPPH radical scavenging assays were performed to determine antioxidative potential. Anti-inflammatory effects were studied using the nitric oxide (NO) inhibition assay in LPS-induced RAW264.7 cells. Extracts of Berchemia berchemiifolia, Sageretia thea, and Ziziphus jujuba had the highest total phenol and flavonoid content values. Extracts of Berchemia berchemiifolia, Paliurus ramosissimus, Rhamnella franguloides, and Sageretia thea had the highest ABTS radical scavenging activities. Berchemia berchemiifolia and Sageretia thea had the highest DPPH radical scavenging activities. Furthermore, extracts of Berchemia berchemiifolia, Berchemia floribunda, Paliurus ramosissimus, Sageretia thea, and Ziziphus jujuba showed strong anti-inflammatory activity through inhibition of NO production. The results of this study suggest that Rhamnaceae extracts can be used as natural antioxidants and immunomodulators.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.250-255
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• 2006

Pinus densiflora is a dominant conifer species in Korea and also distributed in regions of Japan and eastern China. Success in the establishment and productivity of forest tree plantation is largely determined by selection of species and seed source. The provenance tests of Pinus densiflora in Korea are underway. However, the information of the growth performance of Japanese and Chinese provenances are insufficient. Therefore, this study was conducted to evaluate the growth performance of Pinus densiflora Japanese provenances. Data were collected from a provenance trial including established by Korea Forest Research Institude at Chungju in 1970. Six Japanese provenances ($31^{\circ}90^{\prime}{\sim}40^{\circ} 27^{\prime}$ in latitude and $128^{\circ}47^{\prime}{\sim}141^{\circ}80^{\prime}$ in longitude) were included in this trial. Pyeongchang provenance at Kangwon province in Korea was used for reference provenance. At nursery stage, the height and diameter at root collar of six Japanese provenances were smaller than those of Pyeongchang provenance. Among Japanese provenances, Kasahara provenance showed higher growth performance than those of others. The provenance rankings of growth performance were fluctuated until age 11. However, the growth performance of Japanese provenances showed higher than those of reference provenance after age 17. Kirishima-yama provenance showed best growth performance. Simple correlation analysis was conducted to investigate the geographic factors affecting growth performance. The height growth showed negative corelation with latitude of seed origin. Generally, Japanese provenences of Pinus densiflora were well adapted and grown in Chungju. However, it was suggested that further studies on other sites need to generalize the results of this study.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.1
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• pp.10-14
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• 2006

We tested the seed viability of Pinus rigida using accelerated aging to discover optimum times and temperatures far artificially accelerated aging. Seeds were artificially aged at different temperatures and during different tines. The seed viability was affected by the accelerated aging and by temperature with a decline in germination and seed vigor. The aging index of P. rigida seed was 0.31 at $35^{\circ}C$ and seed viability was nearly lost after aging treatment at $40^{\circ}C$ for 15 days. The optimum temperature of P. rigida far the aging test was decided to be approximately $37^{\circ}C$ on the basis of the aging index. Inorganic materials and conductivity of leaching solution from aging seeds increased with the increase of aging period. The accelerated aging test was considered to be a suitable method to evaluate the seed viability of tree species. Because seed characters are much different among tree species, however, more studies need to be done to discover the optimum conditions for aging by tree species.

• Journal of Plant Biotechnology
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• v.41 no.4
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• pp.194-200
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• 2014

Monodehydroascorbate reductase (MDHAR) is an important enzyme that plays a role in the detoxification of reactive oxygen species (ROS) by maintaining reduced pool of ascorbate through recycling the oxidized form of ascorbate. In this study, we isolated a PagMDHAR1 gene from Populus alba ${\times}$ P. glandulosa, and investigated its expression characteristics. The PagMDHAR1 cDNA encodes a putative 434 amino acids containing FAD- and NAD(P)H-binding domains. Southern blot analysis indicated that a single nuclear gene encodes this enzyme. Northern hybridization analysis revealed that PagMDHAR1 is highly expressed in both suspension cells and flower tissues, while its expression levels were enhanced by drought, salt, cold, wounding and ABA. Therefore, PagMDHAR1 might be expressed in response to abiotic stress through the ABA-mediated signaling pathway in this poplar species, suggesting that the PagMDHAR1 plays an important role in the defense mechanisms against oxidative stress.