• Journal of Forest and Environmental Science
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• v.16 no.1
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• pp.1-16
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• 2000

This study was carried out to examine the process of plant succession through vegetation invasion and to select appropriate endemic plant species for rapid stabilization and good visual effect on cut-slopes of forest roads. Establishing total of sixty $1m{\times}1m$ sample plots. fifteen for each forest road constructed in the year of '93 (six-year-old), '95(four-year-old), '97(two-year-old), and '98(one-year-old), the ecological attributes of invading vegetation on cut-slopes were analyzed. The results are summarized as follows: 1. The rate of vegetation coverage was highly associated with soil hardness and aspect of cut-slope. Higher rate of vegetation coverage was caused by larger number of invading plant species. 2. The dominant woody species were Rubus crataegifolius, Rhus chinensis, Lespedeza bicolor, Salix hulteni, Alnus hirsuta, and Pinus densiflora. The visual attractive for the fruit of Rubus crataegifolius and the autumn coloration of Rhus chinensis was noteworthy. The dominant herbaceous species were Youngia sonchifolia, Spodiopogon sibiricus, and Lysimachia clethroides in all study forest roads. Spring flower of Potentilla freyniana and Viola rossii: summer flower of Lysimachia clethroides, Commelina communis, Glycine soja. Persicaria sieboldi, and Oenothera odorata: and autumn flower of Artemisia stolonifera and Impatiens textori were abundant and remarkable. 3. The diversity index of woody species tended to be increased as years passed after construction, and that of herbaceous species were decreased. 4. The dominance of Th of dormancy form was early high in the first year of construction, getting decreased thereafter. And that of MM + M + N was increased as years passed after construction. but that of Ch+H+G+Th+HH was decreased. 5. The degrees of succession were estimated by 359, 111, 97, and 87 for the construction year of '93, '95, '97, and '98. respectively, increased as years passed after construction.

• Horticultural Science & Technology
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• v.18 no.5
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• pp.605-611
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• 2000

This experiment was conducted to examine the effects of foliar application of ethychlozate and ethyclozate mixed with different calcium formulae (clef-non, suical, cell-bine, and calcium acetate monohydrate) on the fruit quality and peel puffing of 'Miyagawa Wase' satsuma mandarin cultivated in a plastic film house. Foliar application of ethychlozate mixed with clef-non or suical showed a result that the 'a' value of peel chromaticity was increased, which are supposed to accelerate peel coloration without peel puffing. The reducing sugar levels of fruits in control, ethychlozate, ethychlozate+celef-non, ethychlozate+suical, ethychlozate+cell-bine, and ethychlozate+calcium acetate monohydrate treatment were 4.98, 5.30, 5.59, 5.00, 5.20, and 4.27%, respectively. Especially, in the case of ethychlozate mixed with clef-non, the reducing sugar level was 0.61% higher than that of control. Sucrose and total sugar content also had a similar trend as that in the reducing sugar contents. The sugar contents of fruits in various ethychlozate treatments mixed with different calcium formulae except those in ethychlozate treatment or ethychlozate treatment mixed with calcium acetate monohydrate were higher than $12^{\circ}Brix$. Especially, the treatment of ethychlozate treatment mixed with clef-non showed the highest sugar content with $12.7^{\circ}Brix$. The ratio of soluble solids to acidity also showed the similar tendency, but there was no significant difference in acidity among the treatments.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.132-138
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• 2016

The objectives of this study were to infer the parameters of forest stand growth functions of STEMS for Cryptomeria japonica stands of Jeju Hannam Experimental Forest, Korea Forest Research Institute, and to investigate the effects of thinning regimes on the patterns of stand growth and carbon absorption. The forest stand growth functions for the potential diameter growth, modifier, crown ratio and mortality are the major ones composing the independent-tree/distance-free forest stand growth simulator, STEMS. The parameters were inferred using the sets of growth data obtained from stem analyses of 39 trees, chosen from 13 sample plots of the forest stands. The effects of thinning regimes on the patterns of stand growth and carbon absorption were investigated by simulating the stand growth patterns of the case study stand with 3 different thinning regimes: no-thinning, early thinning with low intensity and late thinning with high intensity using the simulator. According to the results of the analyses, the different thinning regimes cause significant effects on the growth patterns of average DBH, average height, diameter distribution and stand volume as well as the amount of carbon absorptions.

• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.487-494
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• 2011

The purpose of this study was to investigate self-esteem item goodness-of-fit in sports talented children with socio-psychological aspect, which may be a basis of developing global sports leaders. Fifty children who were selected by 2010 sports talent identification program at Korea National Sport University participated in this study. All participants were asked to answer the questionnaire using Rogenberg (1965) self-esteem scale. Total 8 questions were used with 4 point Likert scale and high point stands for higher self-esteem status. Reliability of Cronbach's ${\alpha}$ was.785 in this study. Frequency analysis, descriptive statistics, and reliability analysis were conducted with SPSS 18.0. WINSTEPS 3.70 (Linacre, 2010) was used for calculating item goodness-of-fit and subject reliability, scale propriety, item goodness-of-fit and item level of difficulty, and level of difficulty were calculated. Statistical analysis showed results as follows. First, it was reported to be suitable for subject reliability in self-esteem as 1.01~1.03 and item reliability as 1.01~1.01. Second, 4 scale was suitable for scale propriety resulting from stage index judgment. Third, 2,7,8 and 3 question showed problems in item goodness-of-fit and item level of difficulty. Finally, scale propriety was reported to be inappropriate for considering sports talented children's ability distribution and scale level of difficulty.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.116-122
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• 2013

We investigated characteristics and self-incompatibility genotypes of 11 crabapple cultivars to introduce a new pollinizer of 'Fuji' apple tree in Korea. Flowering dates of eleven crabapples were two to seven days earlier than that of 'Fuji'. The rate of pollen germination in vitro was ranged from 85.6% to 98.0% except 'Virginia'. Controlled pollination treatment with each crabapples to 'Fuji' increased fruit set rate about 20.4% to 34.4%, the number of seed per fruit about 13.8% to 42.3% and fruit weight about 7.4% to 16.7% compared to open pollination. Tested crabapples were resistant to peach fruit moth, brown leaf spot and sooty blotch in general. A PCR amplification method using S-RNase primers was carry out in eleven crabapples. S-alleles, $S_3$, $S_5$, $S_9$, $S_{10}$, $S_{20}$, $S_{26} from six crabapples were determinated. Through sequencing analysis, $S_5$ ('Manchurian', 'Virginia') and $S_9$ ('Yantaishagou') showed 100% homologous to previous result. Based on our results, it was recommended that 'Manchurian', 'Hopa A', 'Hanyaehanakaidou', 'Spectabilis' could be promising pollinzers for 'Fuji' apple cultivar.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.303-311
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• 2017

In this study, random amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP) analyses were used for evaluation of genetic diversity of 61 kiwifruit (Actinidia spp.) germplasms including domestic and overseas collection cultivars. Forty RAPD primers were detected in a total of 230 polymorphic bands with an average of 5.75. Thirty-two SRAP primer combinations were detected in a total of 204 polymorphic bands with an average 6.38. By unweighted pair-group method arithmetic average cluster analysis using 434 polymorphic bands, kiwifruit germplasms were classified in three groups with similarity value of 0.680. Cluster I consisted of 46 kiwifruit germplasms belonging to A. deliciosa, A. chinensis, A. deliciosa ${\times}$ A. arguta, A. chinensis ${\times}$ A. arguta, and A. chinensis ${\times}$ A. deliciosa. Cluster II consisted of seven germplasms belonging to A. arguta and 'Skinny Green', a cultivar derived from a cross between A. arguta and A. deliciosa. Cluster III consisted of seven germplasms belonging to A. rufa, A. hemsleyana, A. macrosperma, A. polygama, and A. eriantha. Genetic similarity values among tested kiwifruit germplasms ranged from 0.479-0.991, and average similarity value was 0.717. Similarity value was highest (0.991) between NHK0038 (A. deliciosa) and NHK0040 (A. deliciosa), and lowest (0.479) between 'Hayward' (A. deliciosa) and K5-1-22 (A. arguta).

• Journal of Life Science
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• v.21 no.6
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• pp.901-906
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• 2011

In order to investigate the variations on the seed hardness of Pisum sativum distributed in southern area of Korean peninsula, 10 local strains (Choonseong. Ganghwa, Pocheon, Hadong, Haman, Geumneung, Yeongyang, Boseong, Gochang, Namweon), which located from $34^{\circ}26"N$ to $38^{\circ}11"N$, were selected according to their latitudes and geographical distances. The seeds of these strains were collected and their contents of mannose and galactose were analyzed. Mannose contents in the seeds were variable in the range between the highest 10.351 mg/g (Ganghwa) and the lowest 5.962 mg/g (Yeongyang). The contents of galactose were also represented remarkable differences from 7.050 mg/g (Yeongyang) to 19.314 mg/g (Hadong). The local strains were classified into 3 variation types such as the south central type (Namweon, Yeongyang, Geumneung, Gochang), the central type (Choonseong. Ganghwa, Pocheon) and the southern type (Haman, Hadong) and 1 strange strains (Boseong) according to the geographical climatic type, isopleth of warmth index and the ratio of mannose to galactose, which indicate the hardness of seeds in Leguminosae, ranged from 0.46 to 0.94. The variation types are very significant genecologically as an evidence for microevolution related to natual and artificial selection in cultivated plants.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.246-252
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• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.294-299
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• 1991

Eight naked barley cultivars were grown in three production systems to select proper cultivars for dual production of forage and grain and to determine production system x cultivar interactions. In the forage systems. barley was seeded on September 27 and October 17, harvested for forage on November 1. December 10 and February 12 from the September 27 planting (forage system I) and on December 10 and February 12 from the October 17 seeding(forage system II). In the grain-only system, barley was planted on November 5. In forage system I, oven-dried forage yields of eight cultivars ranged 195 to 296kg/10a and Saessalbori and Naehanssalbori yielded significantly higher than the other cultivars recording 280 and 296kg/ l0a, respectively. In forage system II, oven-dried forage yields of eight cultivars ranged 106 to 143kg/10a showing no significant difference among cultivars. Production system x cultivar interactions were significant for lodging at maturity, powdery mildew rating, 1000 kernel weight and grain yield. Leaf area index and biomass at heading, no. of spikes per $m^2$, no. of kernels per spike and test weight were not affected by the production system. Forage utilization delayed heading by 3 days and reduced culm length, spike length, lodging due to heavy rain on May 5 and lodging at maturity except for Songhagbori and Naehanssalbori. Forage utilization did not significantly affect grain yield from the September 27 planting but reduced 9% from the October 17 planting. while Saessalbori and Hyangcheonggwa 1 yielded significantly less than in the grain-only system. Songhagbori appears to be a proper cultivar for dual production of forage and grain in Cheju, considering forage and grain yields. and lodging and powdery mildew resistance.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.169-176
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• 2016

Although chemical fertilizers have a quick effect and broad applicability to agricultural fields, they have caused many problems like increasing soil acidity or decreasing soil organic matters. Environmental-friendly agriculture has been attempted in various ways such as organic agriculture, natural farming, low input and sustainable agriculture. The common interest of all environmental-friendly systems is to decrease burden to agricultural environment by low input of agricultural labor and materials. This study was conducted to estimate overwintering capacity and genetic distance among Chinese Milk Vetch (Astragalus sinicus, CMV) collections based on morphological characteristics and AFLP (Amplified fragment length polymorphism) analysis. Furthermore, the effect of CMV as green manure was observed in mix-cultured paddy fields with rice, sesame and sweet-potato. An another objective of this study was also to compare the pattern of weed occurrence in paddy fields with or without CMV and different rice transplanting times. The CMV collected from Paju district in central region of Korea was successively occurring through self-reseeding without artificial management. However, there was no noticeable difference in growth habit between Paju native CMV and introduced CMV from China which is currently used in farm fields. On the basis of multi-dimensional scaling and tree analyses, there are no significant difference of agricultural growth characteristics among Paju and chinese collections only excepting leaf angle and root length. The flowering time of Gurye collection was fast for 1 week as compared to other collections. AFLP that was commonly used for plant classfication, was applied to exam the genetic variation of CMV collections. Total 579 PCR products and 336 polymorphic fragments were generated using 8 primer pairs.