• Korean Journal of Weed Science
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• v.15 no.4
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• pp.262-269
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• 1995

The reseach was conducted to find out if there are any difference in growth, specific pattern in weed competition, and herbicide response of Korean lawngrass(Zoysia japonica Steud.) in a green house equipped with auto-foggy system. Plant height and leaf stage of Korean lowngrass under foggy condition were increased through all growing stages, whereas the number of tillers and shoot fresh weight harvested at 100 days after seeding were reduced by 24% and 29%, respectively, comparing with non-foggy condition. Weed emergence(total fresh weight) under foggy condition was much greater than that under non-foggy condition. Plant height, number of tillers, number of plant and shoot fresh weight of lawngrass under foggy condition were severely reduced with increasing the duration of competition(above 40 day-competition). Among the herbicides treated, oxyfluorfen completely inhibited plant height of lawngrass regardless of foggy condition, and bensulide considerably inhibited plant height of lawngrass under foggy condition. On the other hand, flazasulfuron did not affect the growth of lawngrass under both foggy and non-foggy conditions. At 40 days after herbicides application, weeding efficacy of bensulide and mecoprop under foggy condition were reduced by 6% and 13%, respectively, comparing with non-foggy condition.

• Asian Journal of Turfgrass Science
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• v.18 no.3
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• pp.141-148
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• 2004

In this report, several factors such as infection time and concentration of bacterial suspension, influencing on transient gene expression in Agrobacterium-mediated transformation were evaluated. An appropriate concentration (O.D 600nm = 1.0-1.2) of bateria and 30 min of infection time showed a higher level of GUS expression. To improve transformation efficiency (TE), friable embryogenic calli (FEC) were bombarded by tungsten particles without plasmid DNA, and then co-cultivated with A. tumefaciens LBA4404 which contains pTOK233 super binary vector, carrying neomycin phosphotransferase (NPTII), hygromycin phosphotransferase (hpt) and$\beta-glucuronidase$ (GUS) genes. Three days after co-cultivation with A. tumefaciens and particle bombardment, FEC cultures were transferred to the selection medium (SM: MS medium supplemented with BA 1mg/l, hygromycin 100mg/l, cefotaxime 250 mg/l and vancomycin 200mg/l). They were cultured for 2 weeks and then transferred to the second SM containing hygromycin 50mg/l, cefotaxime 200 mg/l and vancomycin 100mg/l. Later, stable GUS expression was detected 4 to 6 weeks after transfer to the SM. Further, TE from Agrobacterium-mediated transformation after particle bombardment increased to about 3-folds compared with Agrobacterium-mediated transformation without particle bombardment. In the present study, we established an efficient transformation protocol of zoysiagrass by using A. tumefaciens in the combination with particle bombardment for the first time.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.361-368
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• 2009

Cenangium ferruginosum was known as the causal agent of dieback of pines including Pinus koraiensis and Pinus densiflora. Since the first report of the disease in Korea in 1989, a group dying occurred in Seoul, Gyeonggi, Kangwon and Chungbuk in 2007 spring. Although C. ferreginosum was known as a weak pathogen or a parasite, this disease caused in stressed pine by drought, wounding, extremely cold weather or unusual warm winter. In this study, we explained the features of cenangium dieback with the characteristics of pathogen to understand the trend of disease associated with the climatic change of the world. We collected pycnidia and apothecia from the diseased branches and stems of P. koraiensis and P. densiflora in Gyeonggi, Chungcheong and Gyeongsang province to characterization of pathogen. The fungal development on the diseased branches were observed and the isolates from pycnidia and apothecia were identified as Cenangium ferruginosum by their morphological characteristics and the molecular techniques.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.311-320
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• 1997

This study was carried out to induce and maintain callus from 59 zoysiagrass lines, to know the effective disinfestation method for zoysiagrass stolon as explant and the difference in the response of callus induction among 59 lines, and to investigate the effect of medium, growth regulators, light, temperature, stolon part and internode position on callus induction and emhryogenic callus(E.C.) formation. The treatment of 0.lmg/L $HgCl_2$for 15 min resulted in no contamination and the highest callus induction(46.6%). Callus was induced from the 59 zoysiagrass lines. The callus growth of Z. japonica and Z. sinica was generally better than Z. matrella Ten cell lines whose callus and stolon grow fast in culture and in field, respectively were selected to he used for breeding. Callus induction was the most effective at 2.0mg /L of both 2, 4-D and picloram in MS medium. MS medium was the best for callus induction and growth while LS medium was the best for embryogenic callus and shoot formation. Callus induction and growth was better at 28, 31$^{\circ}C$. than 25$^{\circ}C$. and dark condition was better than light condition in MS me-dium containing 2mg/L 2,4-D. While callus induction was better with node part as explant than with internode part, callus growth and embryogenic callus formation was better with internode part. In 'Japonica 1', the first internode was the most effective in callus induction, but third internode was the best in '$M_2$ X $S_2$'.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.165-169
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• 2010

Fusarium circinatum is the causal agent of the pine disease commonly referred to as pitch canker. In this study, F. circinatum was isolated from the diseased Pinus rigida in the golf courses, Korea. The morphological characteristics and the molecular features of the isolates were investigated to identify the pathogen. Histone H3 gene and IGS rDNA region was analyzed and consequently the isolates identified as F. circinatum. All of them have the same sequences and the mating type was determined as MAT1-1. The inhibitory effect of the methanol extracts from the disease resistant pine species, Pinus koraiensis and Pinus densiflora and a susceptible species, P. rigida were evaluated against the isolate, F. circinatum. As a result, the extracts of P. koraiensis and P. densiflora showed higher antifungal activity than that of the susceptible, P. rigida.

• Asian Journal of Turfgrass Science
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• v.7 no.2_3
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• pp.121-127
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• 1993

This experiment was carried out to compare the varietal differences of dry matter production in rend canarygrass. The varieties examined were Common, Venture, Castor, Palaton and Venture. Reed canarygrass was harvested three times annually, 1st cut(1O, May), 2nd cut(31, July), and 3rd cut(10, Oct.), respectively. The results were summarized as follows ; 1. Dry matter yield were not significant difference between varieties and for the interaction of variety$\times$cut. But, there was significant difference between cuts. 2. There was not significant difference in dry matter yield between the first cut and second cut. But, the dry matter yield of the third cut was poor than the other two cuts. Thus, the average dry matter yield of varieties were 806.1 kg, 730.8kg and 495.8kg /l0a in the first, second and third cut, respectively. 3. In Venture and Palaton, the percentage of dry matter distribution in spring was higher than that of other varieties. In Common, Castor and Vantage, they were not significantly different between the percentage of dry matter distribution in each cut. Above the results suggested that the first group of varieties(Venture and Palaton) were suited to meadow and last group of varieties(Common, Castor and Vantage) were suited to pasture. 4. Average total dry matter yield of varieties was 2,032kg /l0a/yr,(ranged from 1,922kg to 2,180 kg /l0a /yr.)

• Asian Journal of Turfgrass Science
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• v.16 no.2
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• pp.97-106
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• 2002

The oriental beetle, Exomala orientalis, Is the most important insect pest of turfgrass in Korean golf courses. The study was carried out to get practical information on the sampling of E. orientalis in golf courses. Real numbers of E. orientalis larvae were compared with and observed numbers depending on sampling size (5$\times$5 cm, l0$\times$10 cm, 20$\times$20 cm, 30$\times$30 cm, and 40$\times$40 cm) and times (3 to 15 replicates) in Dongrae Benest Golf Club. Over 95% accuracy was obtained between real data and estimated data at the density of over 303 larvae/m$^2$ when the 20$\times$20 cm was sampled with 4 replications. Larval density of E. orientalis was different depending on year and course sites (tee, fairway, rough, green).

• Asian Journal of Turfgrass Science
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• v.2 no.1
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• pp.5-30
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• 1988

The object of this experiments was to know the salt tolerance of Fults and other lawn grasses. Fults, Olympic (Tall fescue, Festuca arundinacea Schred), Ceeping red fescue, Kentucky bluegrass and Zoysia grass (Z. japonica S.) were grown in hydroponics with vermiculite at various concentrations of NaCl. Hoagland's solution was used as the basic solution (control), and the concentrations of Cl to it were 1000, 2000, 3000, 4000 and l5OOOppm, respectively. Each was cultivated under the circumstances during 2 months. The results obtained are summarized as follows: 1.The growth of Fults, Olympic, Creeping red fescue and others were better at Cl lOOOppm than control. In the 5OOOppm application, Fescues become worse and 23.9% of them were withered. In concentration of Cl above 9OOOppm, it was impossible to live. 2.In the l0000~l1000ppm application, Olympic and Kentucky bluegrass were become worse and most of them died. 3.Fults were almost possible to live in the below of 9OOOppm, but they began to die in the above of 10000 ppm. 4.With the increasing concentration of Cl, plants were dwarfed and the number of stems, leaves and roots were reduced, but it was especially observed that the number of stolons of Creeping red fescue were increased at 1000~4000ppm. 5.Fults grass was the most salt tolerant turfgrass, but was impossible to live at salt level of about 36 millimhos (Exchange NaCI conductivity-ppm). Among the grasses, according to salt tolerance, they were arranged as follows. Fults > Zoysia japonica S. > Ky belugrass > Olympic grass > Creeping red fescue 6.The number of leaves, stems, tillers, and dry weight of Olympic grass, Fults and others were increased more at Cl 1OOOppm application than control, but in the above 4OOOppm application, those of plants were decreased. 7.The productivity of all grasses under the experiments was increased at 3.l75millimhos (Exchange NaCi conductivity ppm) in the concentration of Cl. The each dry-weight of Olympic, Creeping red fescue, Kentucky bluegrass and Zoysia grass was decreased at 8.85millimhos, and the weight of Fults grass was also decreased remarkably at 12.20millimhos. 8.As the result of this experiments, most plants grow normally at low concentration of NaCI-l000ppm. That seems to stimulate more the grasses to grow than non-salt.

• Asian Journal of Turfgrass Science
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• v.17 no.1
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• pp.35-44
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• 2003

Popillia quqdriguttata is a serious insect pest in Korean golf courses. The adult feeds on leaves of latifoliate trees and herbaceous plants while the larva feeds on roots of turfgrass. Thus, control of p. quadriguttata adults was tried with registered insecticides in golf courses in Korea. The insecticides used in the experiments were carbaryl + phosalone WP, chlorpyrifos + diflubenzuron WP, chlorpyrifos-methyl EC, deltamethrin EC, etofenprox WP, etofenprox + diazinon WP, etofenprox + tebufenozide EC, fenitrothion EC, imidacloprid SC, pyraclofos WP, and tralomethrin EC. Mortalities of P. quadriguttata were over 95% in carbaryl + phosalone WP, chlorpyrifos + diflubenzuron WP, etofenprox + diazinon WP, and fenitrothion EC at petri dish and in greenhouse. In the field test, corrected mortality of P. quadriguttata was 95.2% and 80.9% in carbaryl 40% +phosalone 20% WP and fenitrothion 50% EC, respectively. Spreading agent enhanced toxic effect of used insecticides to p. quadriguttata adults except carbaryl + phosalon 20% EC. p. quadriguttata adult was firstly observed to feed on leaves of Canna generalis at the Yongwon golf club in Jinhae, Gyeongnam and Prunus ameriaca var. ansu and p. salicina at the Anyang Honest golf club in Gunpo, Cyeonggi. Therefure, host plants off quadriguftata became 29 species of 26 genera in 19 families. Zoysia matreila at the fairway and roughs of Anyang Benest golf club was damaged by p. quadriguttata larvae in Octomber, 2002 and not recovered in April, 2003. Damaged turfgrass became yellowish and wilted and that retarded recovering in the following spring.

• Asian Journal of Turfgrass Science
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• v.21 no.1
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• pp.9-21
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• 2007

Research was initiated to examine establishment efficiency of zoysiagrass by plugging. Zoysiagrass is known to be a slowly establishing turfgrass species. Properly-treated zoysiagrass seed can speed up the establishment rate, while initial irrigation practice is intensively required after seeding. A planting method with small plugs($2.5{\times}2.5cm$) from seeding can overcome initial watering requirement. Establishment speed, however, can vary with planting dates, planting spaces, and plastic film cover in early stage. Establishment characteristics were investigated for two years by planting dates that were April 5, May 18, July 13, August 24 and October 29 in 2004 and April 6 in 2005. They were also compared with three different spaces($20{\times}20,\;25{\times}25,\;and\;30{\times}30cm$) and three different fertilizer levels(15, 30, and $45g\;N{\cdot}m^{-2}$). Ground coverage reached to 90% in plugs of 'Zenith' zoysiagrass planted on April 5. It increased suddenly in period of July to August, resulting in about 50% of full establishment rate. Establishment rates were significantly faster over 9% in plugs spaced at $20{\times}25cm$ than in those at $30{\times}30cm$. No significant differences were observed on the stolen number and stolen length in the study. Survival rate in zoysiagrass plug was over 90% at all plantings. These results demonstrated that zoysiagrass establishment using small plug from seeding is considered to be a safe and efficient method.