• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.589-605
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• 2012

This study was conducted to identify allelopathic effect of Ganghwa domestic Artemisia spp., named Sajabalssuk and Ssajuarissuk, for various receptor plants including clover (Trifolium repens L.), alfalfa (Medicago sativa L.), lawn grass (Zoysia japonica Steud.), dandelion (Taraxacum platycarpum Dahlst.), and dahurianpatrinia (Patrinia scabiosaefolia Fisch. ex Trevir). Receptor plants were treated with the aqueous and essential oil extract of Artemisia plants. In consequence, their allelopathic effects were evaluated by measuring seed germination rates, seedling growth, and dry weights of the receptor plants. The seed germination and seedling growth of the receptor plants were inhibited by all treatments of both aqueous and essential oil extracts of the Artemisia plants, and, in addition, the inhibitory effects were increased according to the higher concentration. Among the donor plants, A. $sp.^*III$ showed most effective allelopathic effect. Comparing the alleopathic effect among the receptor plants, seed germination was most inhibited in lawn grass while inhibitory effect of seedling growth was comparatively higher in dandelion. Although inhibitory effects were comparatively lower, the allelopathic effects of Artemisia plants were identified in clover and alfalfa since the seedling growth of these plants were inhibited more than 70%. Thus, in result, Ganghwa domestic Artemisia spp. could be possibly used for weed control since natural products of the plants showed inhibitory effects on seed germination and seedling growth of various receptor plants.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.648-655
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• 2010

This study is the first comprehensive report on the molecular cloning, structural characterization, sequence comparison between wild and mutant types, copy number in the genome, expression features and activities of a gene encoding 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in Korean lawn grass ($Zoysia$ $japonica$). The full length cDNA of the EPSPS from Korean lawn grass ($zj$EPSPS) obtained from a 3' and 5' RACE method was 1540 bp, containing a 1176 bp ORF, a 144 bp leader sequence (5' UTR) and a 220 bp 3' UTR, which was eventually decoded 391 amino acid residues with a molecular mass of 41.74 kDa. The Southern blot detection of the $zj$EPSPS showed that the gene exists as a single copy in the Korean lawn grass genome. Sequence comparison of the $zj$EPSPS gene demonstrated that the glyphosate-tolerant mutant (GT) having a Pro-53 to Ser substitution in the gene seems to have a preferred binding activity of the enzyme to phosphoenol pyruvate(PEP) over glyphosate, which allows the continuous synthesis of aromatic amino acids in the shikimate pathway. From the Northern blotting analysis, the $zj$EPSPS was found to be highly expressed, with continuous increase until 36 hours after 0.5% glyphosate treatment in both wild and mutant samples, but 1.5-fold higher EPSP synthase activity was observed in the tolerant mutant when exposed to the glyphosate treatment. The molecular information of the $zj$EPSPS gene obtained from this study needs to be further dissected to be more effectively applied to the development of gene-specific DNA markers and zoysiagrass cultivars; nevertheless, the glyphosate-tolerant mutant having the featured $zj$EPSPS gene can be provided to turfgrass managers for weed problems with timely adoptable management options.

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.123-127
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• 2009

This study was carried out to investigate the classification and the growing characteristics of biennial weed species in a newly formed transplanting lawn grass land. Measuring size in the experimental plot was $1{\times}1m$ in the 9 different locations, and experimental design was randomized complete plot with 3 replications. The results obtained are summarized as follows. 1) Weed species in a newly formed lawn field are consisted of 29.4% of Cruciferae, 29.4% of Compositae, 23.5% of Caryophyllaceae, 11.8% of Gramineae, and 5.9% of Labiatae family 2) Emerging percentage of weed species are consisted of 47.1% on October, 41.2% on November, 5.9% on both September and December, respectively. 3) Distribution rate about flowering time of weed species was in order of 58.5% on May, 23.5% on April, 11.8% on March, and 5.9% on June. 4) Weed species were grouped according to the plant height. It was observed that below 20cm, 20-40cm, 40-60cm and above 60cm of plant height were 23.5%, 47.1%, 17.6% and 11.8%, respectively.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.333-344
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• 2017

This study was conducted to examine the effect of cool-season grass overseeding on the green period, turf quality and density in zoysiagrass lawn. Treatments were perennial ryegrass (PR) overseeding ($60g\;m^{-2}$) on medium-leaf type zoysiagrass, Kentucky bluegrass (KB) overseeding ($20g\;m^{-2}$) on medium-leaf type zoysiagrass and narrow-leaf type zoysiagrass, and no overseeding on medium-leaf type zoysiagrass. Overseeding of KB or PR effectively provided quality improvement of zoysiagrass lawn by extending green-period about one month in spring and two months in fall season. PR overseeding showed quick green cover within 2-3 weeks but decreased the quality of overseeded zoysiagrass lawn during the summer season. Whereas, KB overseeding showed slow green cover taking two to three month after seeding but provided stable and good turf quality throughout the years. KB or PR overseeding significantly increased the turf density of zoysiagrass lawn except the period of summer depression of PR. The ground coverage of cool-season grasses ranged from 30 to 80% with considerable seasonal variation. As a result, KB and PR have their strengths and weaknesses as an overseeding material. Thus, the use of KB and PR as a mixture would provide better overseeding performance in zoysiagrass lawn.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.263-270
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• 1999

In country, for 2002 World-cup the peak is to construct soccer playground. the stabilizing method by additives is mainly applied of permanent improvement for bearing capacity of structure foundation and for strength, durability and transformation of road pavement layer except for construction machine's trafficability and bearing capacity. This study is on soft ground improvement of $\bigcirc$$\bigcirc$ world-cup stadium field. construction field constitutes of very various layers and after construction the lawn grass should be planted on the surface of the earth and in addition, chemical effects should be limited from improved ground layer. Mixing soft clay in field with three domestic representative additives, it evaluated the unconfined compression strength. In the results, after curing during 28 days the objective strength has been obtained on about 5% combination ratio.

• Asian Journal of Turfgrass Science
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• v.1 no.1
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• pp.18-29
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• 1987

This study was carried out to examine the effect of nitrogen application and clipping interval on the characteristics of several turf components of korean lawngrass for the basic data of lawn management. It was treated by Split plot design with three replications. The main plots were nitrogen levels with 0, 350, and 700kgN / ha, and the sub plots were clipping intervals with 10, 20, and 30 days The results obtained are summarized as follows ; 1. Increasing the rate of nitrogen fertilizer and frequent clipping increased tiller number of korean lawngrass and the maximum number of tillers obtained in October were recorded from 700kgN application and clipping treatment of 10 days interval. Meanwhile, treatment of 350kgN with 10 days clipping interval increased tillers much more than those of 700kgN with 20 and 30 days clipping intervals. 2. The average number of green leaves occurred during the growth period maximized by applying 700 kgN and clipping 10 days interval. 3. Increasing tiller numbers significantly decreased tops DM weight per tiller by clippng plants at interval of 10 and 20 days, irrespective of nitrogen applied, and with nil N, at the interval of 30 days. By applying 700kgN however, tops DM weight per tiller increased as the number of tillers increased consistently. 4. The highest tops DM weight was achieved from late August to early September by applying 350 and 700kgN. 5. During the growth period, nitrogen application increased unders(stolon+root) DM weight, and, at the same level of nitrogen applied, the increase in stolon DM weight enhanced by lengthening the clipping interval to 30 days. 6. Nitrogen efficiency to green leaves, stolon nodes and DM weight of root with high nitrogen was achieved as clipping interval was shortened.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.1
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• pp.53-68
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• 1992

This study was carried out to estimate the recreation carrying capacity of lawn areas in parks. Recreation carrying capacity in this study is composed of two parts, ecological carrying capacity and psychological carrying capacity. As the first part, this paper deals with the treading times criteria based on the tolerence of the turf to treading pressure. The plant material used for this study was Zoysia japonica, and the treading experiment was done in the experimental fields in Kyungju and Suwon, Korea. The major results of the first part of the study are summarized as follow: 1. As shown in annual change of the growth of the turf, The growth of turt grass was represented by the number of leaf. 2. The tolerance to treading was not significantly different by the time of treading treatment. And the tolerance varies depending on growth rate of grasses, which showed significant relationship with precipitations. 3. From the result of different numbers of simulated treading treatment, the damage of the turf was increased by the increase of the frequency of treading. And the damage was very serious within short period(about 20 days) in high frequency(over 20 times/day) of treading treatment. But low frequency(1∼3times/day) of treading shows good effects on the growth of the turf. 4. The criteria of treading number per day for each carrying capacity level are estimated as 7 times/day for optimum carrying capacity, 13 times/day for standard carrying capacity, and 20 times/day for critical carrying capacity.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.368-372
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• 1998

A field assay was conducted to study whether the by-product of Autoclaved Lightweight Concrete(ALC) could be used as a silicate fertilizer for Korean Zoysiagrass. ALC application rates (0, 2.0, 4.0, 6.0 and $8.0Mg\;ha^{-1}$) were investigated for their effects on growth status, mineral nutrient concentrations, yield of fresh and dry matter of lawn grass and soil properties after experiments. The number of stolon and length of stolon at 180 day after Zoysiagrass transplanting were increased in the treatemnt of $2.0{\sim}6.0Mg\;ha^{-1}$ of ALC application, but those of $8.0Mg\;ha^{-1}$ of ALC plot were deceased with excess of ALC. The fresh weight and dry matter at harvesting time of lawn grass treated with $6.0Mg\;ha^{-1}$ of ALC was heavier than those of other ALC plots. There were statistically significant between the number of stolon and length of stolon remarkably. Mineral nutrient contents such as Si and Ca in Zoysiagrass were increased by higher ALC application, while T-N, available P and K were no difference with application lavel of ALC. Soil pH and Si contents in soil after experiment were increased by ALC application remarkably.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.450-456
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• 2016

Rhizoctonia leaf blight (large patch) has become a serious problem in Korean lawn grass, which is extremely hard to treat and develops mostly from the roots of lawn grass to wither it away. Rhizoctonia leaf blight (large patch) is caused by Rhizoctonia solani AG2-2 (IV). To develop zoysia japonica with strong disease tolerance against this pathogenic bacterium, ${\beta}-1,3-glucanase$ was cloned from zoysia japonica, which is one of the PR-Proteins known to play a critical role in plant defense reaction. ${\beta}-1,3-glucanase$ is known to be generated within the cells when plant tissues have a hypersensitive reaction due to virus or bacterium infection and secreted outside the cells to play mainly the function of resistance against pathogenic bacteria in the space between the cells. This study utilized the commonly preserved part in the sequence of corn, wheat, barley, and rice which had been researched for their disease tolerance among the ${\beta}-1,3-glucanase$ monocotyledonous plants. Based on the part, degenerate PCR was performed to find out the sequence and full-length cDNA was cloned. E.coli over-expression was conducted in this study to mass purify target protein and implement in vitro activation measurement and antibacterial test. In addition, to interpret the functions of ZjGlu1 gene, each gene-incorporating plant transformation vectors were produced to make lawn grass transformant. Based on ZjGlu1 protein, antibacterial activity test was conducted on 9 strains. As a result, R. cerealis, F. culmorum, R.solani AG-1 (1B), and T. atroviride were found to have antibacterial activity. The gene-specific expression amount in each organ showed no huge difference in the organs based upon the transformant and against 18s gene expression amount.

• Journal of Environmental Science International
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• v.26 no.9
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• pp.1057-1072
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• 2017

In order to investigate the effect of air temperature reduction on an urban neighborhood park, air temperature data from five inside locations (forest, pine tree, lawn, brick and pergola) depending on surface types and three outside locations (Suwon, Maetan and Kwonsun) depending on urban forms were collected during the summer 2016 and compared. The forest location had the lowest mean air temperature amongst all locations sampled, though the mean difference between this and the other four locations in the park was relatively small ($0.2-0.5^{\circ}C$). In the daytime, the greatest mean difference between the forest location and the two locations exposed to direct beam solar radiation (brick and lawn) was $0.5-0.8^{\circ}C$ (Max. $1.6-2.1^{\circ}C$). In the nighttime, the mean difference between the forest location and the other four locations in the park was small, though differences between the forest location and locations with grass cover (pine tree and lawn) reached a maximum of $0.9-1.7^{\circ}C$. Comparing air temperature between sunny and shaded locations, the shaded locations showed a maximum of $1.5^{\circ}C$ lower temperature in the daytime and $0.7^{\circ}C$ higher in the nighttime. Comparing the air temperature of the forest location with those of the residential (Kwonsun) and apartment (Maetan) locations, the mean air temperature difference was $0.8-1.0^{\circ}C$, higher than those measured between the forest location and the other park locations. The temperatures measured in the forest location were mean $0.9-1.3^{\circ}C$ (Max. $2.0-3.9^{\circ}C$) lower in the daytime than for the residential and apartment locations and mean $0.4-1.0^{\circ}C$ (Max. $1.3-3.1^{\circ}C$) lower in the nighttime. During the hottest period of each month, the difference was greater than the mean monthly differences, with temperatures in the residential and apartment locations mean $1.0-1.6^{\circ}C$ higher than those measured in the forest location. The effect of air temperature reduction on sampling locations within the park and a relatively high thermal environment on the urban sampling locations was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with a high sky view factor and surface types with high evapotranspiration potential (e.g. grass) showed the maximum air temperature reduction. In the urban areas outside the park, the low-rise building area, with a high sky view factor, showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, while in the nighttime the area with high-rise buildings, and hence a low sky view factor, showed high air temperature due to the effect of terrestrial (longwave) radiation emitted by surrounding high-rise building surfaces. The effect of air temperature reduction on the park with a high thermal environment in the city was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with high sky view factor and surface types (e.g., grass) with evapotranspiration effect showed maximum air temperature reduction. In the urban areas outside the park, the high sky view factor area (low-rise building area) showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, but in the nighttime the low sky view factor area (high-rise building area) showed high air temperature due to the effect of terrestrial (longwave) radiation emitted surrounding high-rise building surfaces.