• Weed & Turfgrass Science
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• v.2 no.2
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• pp.164-169
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• 2013

Alternatives to commercial chemical herbicide are currently being searched and tested due to the numerous adverse effects of commercially available herbicides to the environment. Barnyardgrass (Echinochloa crusgalli) is an important weed species around the world, especially in paddy rice fields. This study focuses on the favorable effects of mixing pyroligneous acids with commercial liquid herbicides. Seedlings were transplanted and grown under greenhouse conditions. The effect of treatment time or leaf-stage on herbicide-pyroligneous acid efficacies was checked, coupled with isolation and quantification of biochemical compounds. Results revealed that herbicide treatment at early post emergence (2~3 leaf stage) of Echnochloa crus-galli leads to effective control. Both liquid herbicides affected fatty acid, protein, and amino acid syntheses as reflected on their contents. The influence of wood vinegar (WV) or rice vinegar (RV) on these compounds was not thoroughly verified due to lack of information on the pyroligneous products. We observed that mixing WV or RV with BCB (bentazone + cyhalof-butyl) gives more favorable results than BUC (butachlor + clomazone), mixed with WV or RV. The result would indicate the potential of mixing pyroligneous acid in reducing herbicide application rate.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.281-288
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• 1997

This study was performed to find out the mineral cycles of sulphur in dynamic grassland ecosystems in a steady state condition at the northwest side on Mt. Kwanak. The experimental results may be summarized on the communities of a Zoysia japonica and a Miscanthus sinensis as follows. As compared with some properties of the surface soils among two semi-natural grasslands, sulphur war greater quantity in a Miscanthus sinensis than in a Zoysia japonica on Mt. Kwanak . For the case of steady production and release, the raion of annual mineral production to the amount accumulated on the top of mineral soil in a steady state provides the estimates of release constant k. The release constants on sulphur of the litter were 0.54 in a Zoysia japonica and 0.36 in a Miscanthus sinensis grassland. The half times of S required for the release or accumulation of the litter on the grassland were 1.28 years in a Zoysia japonica and 1.93 years in a Miscauthus sinensis The amounts of annual cycles for sulphur in the grassland ecosystem under the steady-state conditions were 20.65g /$m^2$ in a Zoysia japonica and 26.28g /$m^2$ in a Miacanthus sinensis grassland. Key words: Zoysia japonica Miscanthus sinensis Mt. Kwanak, Sulphur, Mineral cycles.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.50-56
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• 2012

The objectives of this research were to quantify resistance levels of transgenic rice expressing the bar gene to glutamine synthetase (GS)-inhibiting, and methionine sulfoximine and photosynthesis-inhibiting herbicide, paraquat, and compare the ammonium accumulation, chilling injury, and yield between transgenic and non-transgenic rice. The transgenic rice lines were 45-96-fold more resistant to glufosinate-ammonium than non-transgenic rice. The transgenic rice lines were also 18-fold more resistant to methionine sulfoximine, but was not resistant to paraquat, which has different target site. Glufosinate-ammonium increased the ammonium accumulation in leaves of non-transgenic rice plants, but had minimal or no effect on leaves of transgenic lines. The transgenic lines except for 258, 411, 607 and 608 were more susceptible during chilling and recovery than non-transgenic rice plants. The yield of transgenic lines 142, 144, 258 and 608 was similar or higher than that of non-transgenic rice in pot conditions.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.30-42
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• 2011

Moths were collected to survey turfgrass pest and to compare species diversity from Jinju Country Club in Jinju, Gyeongsangnamdo, Korea, every 10 days using 200W mercury light trap from middle May to late October in 2008. As the results, only 23 individuals of Pseudaletia separata, Spodoptera depravata, Spodoptera litura, Agrotis segetum, and Agrotis ipsilon were collected as turf grass insect pests. However, 2028 individuals of 388 species in 22 families were collected in total. Dominant species was Culcula panterinaria, Fentonia ocypete, Hypsopygia regina, Culcula panterinaria, Flavocrambus striatellus, and Diarsia camescens in May, June, July, August, September and October, respectively. Species diversity was not different between two surveyed sites, but different among surveyed time. Species richness was more higher in hole 11 (Hole was surrounded by natural forest and located near pond) than hole 15 (Hole was located at the top part of mountain). Dominance index of moth was increased from October compared with diverse index and richness index were decreased from October. A large number of species and individuals were recorded in Noctuidae (502 individuals in 131 species), Geometridae (491 individuals in 84 species), Pyralidae (386 individuals in 73 species), and Notodontidae (277 individuals in 25 species). These four families were 80.9% out of all the collected species.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.23-34
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• 2009

Research was initiated to investigate early establishment characteristics and germination pattern of tall fescue(TF, Festuca arundinacea Shreb.). Four varieties of TF were evaluated in the study. Experiment was conducted under a room temperature condition of $5^{\circ}C$ to $25^{\circ}C$(natural conditions). Daily and cumulative germination patterns were measured and analyzed on a daily basis. Significant differences were observed in germination patterns, days to the first germination, days to 50% germination, days to 75% germination, and germination percentage with different environments and varieties. Germination percentage was variable with varieties at the end of study. It was 85.25 to 97.00% under natural conditions. There were considerable variations in early germination characteristics and patterns among the entries according to different conditions. The first germination was initiated between 7 and 9 DAS(days after seeding) under natural conditions, being 2 to 3 days later as compared with ISTA conditions. It was 11 to 12 DAS in days to the 50% germination, which was 3 to 4 days after the first germination. Days to the 75% germination were 12.38 to 14.29 DAS, being 1.55 to 4.77 days slower as compared with ISTA conditions. Olympic Gold was regarded as the fastest variety and Tar Heel II was slowest. Data from this study demonstrated that information on differences in germination characteristics and patterns among varieties would be usefully applied for TF establishment such as golf course construction.

• Weed & Turfgrass Science
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• v.6 no.3
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• pp.235-248
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• 2017

This study was initiated to investigate seed germinating vigor, germination speed, and establishment characteristics of Festuca species under natural conditions ($5-25^{\circ}C$). Germination rate was 62.0% in CRF 'Audubon' to 97.0% in TF 'Olympic Gold'. It was greater with TF over fine-type fescues, being TF>SF>CF, HF>CRF. The germination speed, measured as days to seed germination of 50% through 80%, was fastest with TF, medium to high with CF, medium with HF and SF, and slowest with CRF. However, it was approximately 4 days slower under natural conditions, as compared with that under alternative conditions ($15-25^{\circ}C$). Germination peak time was much faster with TF. It ranged from 0.73 to 1.84 days with TF, being 1.45 days in average. But it varied with 2.16 to 11.75 days among fine-type species. The peak time was longer in order of SFCF>SF>HF>CRF.

• Asian Journal of Turfgrass Science
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• v.22 no.1
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• pp.57-64
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• 2008

This study was carried out to investigate the deterioration rate and conditions of natural lawn play grounds from 71 schools in Daejeon metropolitan city. Also, we investigated the grasses and wild flowers of 33 families and 101 species on five additional school grounds. One year after planting in 71 schools from 2002 to 2004, we found out that the school lawn grounds coverage were deteriorated up to 51% in elementary schools, 76% in middle schools, and 42% in high schools. There are 45 species on the two school grounds located in mountain areas, 20 species on the three grounds located in downtown areas. There are 20 species in Compositae family, 17 species in Gramineae, 7 species in Polygonaceae, and 7 species in Leguminosae, 6 species in Caryophyllaceae, five species in Cruciferae, and 4 species in Cyperaceae.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.219-229
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• 2018

We isolated Streptomyces scopuliridis KR-001 that produced herbicidal active metabolite(s) against several grass and broad leaf weeds. In this study, potential as natural herbicide of mutant N-29 broth filtrate of S. scopuliridis KR-001 was investigated to Ambrosia artemisiifilia in a greenhouse and field condition. The broth filtrate of mutant N-29 by foliar application showed a strong herbicidal activity to A. artemisiifilia with leaf stage in a greenhouse condition. Also, field trial of foliar application within treatment range had effectively controlled with early and middle stage of A. artemisiifilia at the natural habitats. Phytotoxic symptoms of mutant N-29 broth filtrate by foliar application were wilting and discoloration, and burn-down of leaves and finally plant death. These results suggest that mutant N-29 broth filtrate is considered possible as a natural herbicide for controlling environmentally friend to invasive alien plant such as A. artemisiifilia and may provide a new lead molecule for a more efficient herbicide.

• Asian Journal of Turfgrass Science
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• v.10 no.2
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• pp.105-115
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• 1996

To find out the mineral cycles of calcium, magnesium and sodium in dynamic grassland cosystems in a steady state condition, this investigation was conducted along the northwest side on Mt. Kwanak. The experimental results may he suromarized on the communities of a Zoysia japonica and a Miscanthus sinesis as follows. As compared with some properties of the surface soils among two semi-natural grasslands, cal- cium (Ca) was greater quantity in a Zoysia japonica, whereas, in a Miscanthus sicensis, sodium (Na)and magnesium (Mg) were greater in Mt. Kwanak. For the case of steady production and release, the ratio of annual mineral production to the amount accumulated on the top of mineral soil in a steady state provides the estimates of release constant k. The release constants of Ca, Mg and Na of the litter were 0.42, 0.25 and 0.29 in the Zoysia japonica grassland, and were 0.41, 0.54 arid 0.62 in the Miscanthus sinensis grassland, respect- ively. The half times of Ca, Mg and Na required for the release or accumulation of the litter on the grassland were 1.65, 2.77 and 2.39 in the Zoysia japonica, and were 1.69, 1.28 and 1.12 in the Miscauthus sinensis, respectively. The increasing order of the turnover parameters of the elements was Ca, Na and Mg in the Zoysia japonica grassland, and was Na, Mg and Ca in the Miscanthus Si nens is grassland. The amounts of annual cycles for Ca, Mg, Na in the grassland ecosystem under the steady-state conditions were 1.29, 0.20 and 0.12 g /m$^2$ in the Zoysia japonica grassland and 3.91, 1.04 and 0.61 g /m$^2$ in the Miscanthus sinensis grassland.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.93-105
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• 2006

The construction of golf courses has had adverse effects on the natural landscape and delicate ecosystem of Korea. Efficiency in planning and design was necessary to minimize the environmental impact of the original construction. However, the ordinal design methods have limited the data processing by the massive scale of the project of golf course development. Conventional design methods did not have a proper tool for alternative plans on pre-estimation of landscape destruction or minimizing of the environmental impact. Therefore, advanced computerized techniques need to be adapted for golf course design to solve the problems concerning the environmental impacts. Geographic information system (GIS) was applied on the process of geographical data input and analysis through the final outputs. Simulation works by the total database management enable the pre-investigation of the design In view of an assessment of environmental impacts. It is also possible to evaluate plans easily and propose the alternatives properly. Precise quantity calculation of engineering works by computer system should be guaranteed scientific, economic, and environmentally-sound.