• Asian Journal of Turfgrass Science
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• v.14 no.1
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• pp.263-272
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• 2000

A field study was carried out to find out the effective chemical for controlling algae without visual injury on creeping bentgrass golf greens. The results were as follows. 1. Chlorothalonil(75%), Metalaxy(7.5%)+Mancozeb(56%) and Mancozeb(75%) did not injure creeping bentgrass. Only chlorothalonil(75%) effectively controlled algae regardless of concentration among above mentioned 3 fungicides. 2. Mancozeb frequently used on golf courses showed about 50% effect on controling algae in this study. 3. Mancozeb(75%)+Copper hydroxide(73%) and Mancozeb(75%)+Streptomycin(100%) had good effects on algae control while injuring creeping bentgrass. 4. Copper hydroxide(73%) and copper sulfate basic(58%) $including\ulcorner$Cu$\lrcorner$showed effective algae control but caused injure creeping bentgrass. 5. Streptomycin has been scarcely used on golf greens but streptomycin(20%) 0.1g a.i/$\m^2$ had good control of algae and durability without injuring creeping bentgrass.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.327-335
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• 2009

Creeping bentgrass (Agrostis stolonifera L.) is economically important as the principal turfgrass species for golf course greens and fairways in temperate climates around the world. As the utilization area of the turfgrass species increases recently, the demand for new and improved cultivars increases. Thus, substantial progress has been made in applying modern biotechnology to develop genetically engineered (i.e., biotech) creeping bentgrass with new traits that eluded the breeders. This review article addresses the advances made in developing biotech creeping bentgrass, which are categorized in the following topics: (i) genetic transformation of creeping bentgrass, (ii) development of various biotech creeping bentgrasses by genetic engineering, and (iii) progresses in the deregulation of herbicideresistant creeping bentgrass.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.1
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• pp.101-110
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• 1994

A field study was carried out to investigate the visual injury of zoysiagrass and creeping bentgrass by the application of various herbicides the result were as follows. 1. Trifluralin + benefin and dithiopyr did not injure creeping bentgrass and zoysiagrass. 2. Creeping bentgrass was safe while zoysiagrass was slightly injured within acceptable level with benefin. 3. Oryzalin caused injury both on creeping bentgrass and zoysiagrass. However, the injury of zoysigrass was within acceptable level while the injury of creeping bentgrass increased without acceptable level when applied at>5kg/ha. 4. Creeping bentgrass was tolerant to pendimethalin only when treated at<3.4kg/ha whereas zoysiagrass was tolerant regardless of rate. 5. Creeping bentgrass treated with fenoxaprop, oxadiazon, and bensulide were severely injured. However, turfgrasses treated with bensulide recovered rapidly when compared with fenoxaprop and oxadiazon. 6. Zoysiagrass treated with 2,4-D, dicambe, bentazon was safe when applied at mid summer.

• The Plant Pathology Journal
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• v.27 no.3
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• pp.232-341
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• 2011

Pink snow mold, caused by Microdochium nivale, is a major disease on cool season turfgrasses in golf courses in northern Unites States. The relative susceptibility of 17 commercial cultivars of three bentgrass species (creeping, colonial and velvet bentgrass) to Microdochium nivale and the aggressiveness of M. nivale eight isolates obtained from infected turfgrasses on golf courses in Wisconsin were evaluated under controlled conditions. For the field trial, susceptibility of 2 year-old 12 commercial bentgrass cultivars was evaluated after inoculating three M. nivale isolates in the fields. There were significant differences in disease severities among the three bentgrass species, particularly between tetraploids (creeping and colonial) and diploid (velvet) species, and among cultivars within each species, indicating that there are varying levels of susceptibility in species and cultivars to M. nivale. Host resistance by days of cold hardening was confirmed, by detecting the resistance by 30 days of cold hardening treatments. In field trial, susceptibility of 12 bentgrass cultivars was highly correlated to the results obtained from growth chamber experiments. The positive correlation of the susceptibility between growth chamber experiments and field trials demonstrates that the growth chamber method is a useful technique for saving time, space and labor to evaluate efficiently pink snow mold susceptibility of bentgrass cultivars. This study could be applied to evaluating susceptibility of bentgrass to pink snow mold and also predicting a prospective evaluation of bentgrass cultivars to pink snow mold in fields in a breeding program.

• Asian Journal of Turfgrass Science
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• v.14 no.1
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• pp.273-280
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• 2000

This study was conducted to evaluate an efficiency of plant growth regulator trinexapacethy(Primo) on the growth response of bentgrass and the change to soil water content in bentgrass green. Based on the results of the study, the following results were observed. 1. During four weeks after treatment, the visual color and turfgrass density of all the treated plots with trinexapac-ethyl(Primo) were more improved rather than without. Two treatments trinexapac-ethyl /$0.02mL\m^2$ and $0.04mL/\m^2$ were more favorable than other treatments. 2. It suggested that optimum rate to reduce the bentgrass growth and to increase the turfgrass density was the trinexapac-ethyl $0.04mL/\m^2$. 3. For six weeks after treatment, all treated plots were not significantly different (P<0.05) in turfgrass root length and root dry weitht. 4. In the treated plots with trinexapac-ethyl $0.04mL/\m^2$ for 25days in bentgrass green, soil water consumption was approximately 35% to 40% compare to the non-treated control.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.3
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• pp.167-170
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• 2013

This study examined the growth performance and field evaluation of the dual herbicide-resistant transgenic creeping bentgrass plants. The effect of glyphosate treatment on the herbicide resistance of the transgenic creeping bentgrass plants was determined, and the non-transgenic control plant withered at the concentration $11{\mu}g/mL$ or higher whereas the transgenic creeping bentgrass plants survived the treatment at the concentration of $3,000{\mu}g/mL$, and the increase of the plant length was repressed as the glyphosate treatment concentration was increased. At field evaluation, glufosinate-ammonium and glyphosate were simultaneously treated to investigate the weed control effect. The results showed that more than 90% of the weeds withered four week after herbicide treatment, while the transgenic creeping bentgrass plants continued to grow normally. Therefore, the dual herbicide-resistant creeping bentgrass plants may be able to greatly contribute to the efficiency of weed control and to the economic feasibility of mowing in places such as golf courses.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.135-139
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• 2012

Creeping bentgrass (Agrostis stolonifera) is one of the most popular turfgrasses for high-quality playing surface such as putting green on golf courses and athletic fields. Continues damage such as divot injury on creeping bentgrass is major issue to maintain golf course properly. Although plentiful researches to maximize divot resistance have been reported, minimal research has focused on relation between nitrogen (N) sources and divot resistance. The study was conducted to determine the effect of N source for turfgrass divot recovery and overall tee performance. Eleven fertilizer treatments as N sources were applied to creeping bentgrass 'Penncross'. Before the first application, divot injuries were simulated by removing a core of soil and turfgrass from established plots and backfilling with native soil. Data collection included turfgrass color and quality. N release speed did not influenced divot recovery. Frequency of urea application had no effects on divot recovery. Urea with split application had no difference with no treatment for divot recovery. Polyon product especially polyon mini (41-0-0) had the best performance for divot recovery and for maintaining better turfgrass quality. Overall, small particle size of slow-release N form would influence creeping bentgrasss to recover divot damage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.267-276
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• 2006

To investigate the physiological responses to winter freezing stress naturally occurring, the level of lipid peroxidation and enzymatic antioxidant responses were compared between zoysiagrass and creeping bentgrass during overwintering. Root mortality of creeping bentgrass was significantly higher than zoysiagrass at January. Root growth of creeping bentgrass was nearly parallel with temperature fluctuation, while zoysiagrass showed little changes in root growth until the end of April. Total nonstructural carbohydrate of zoysiauass was 10% higher than creeping bentgrass. Malondialdehyde(MDA) content in creeping bentgrass was 2-fold higher than that of zoysiagrass. The peroxidase(POD) activity of creeping bentgrass in January was 4.2 times higher, while superoxide(SOD) and catalase(CAT) activities lowered 22% and 67%, respectively, compared to zoysiagrass. These results suggest that zoysiagrass roots much properly operate cold tolerance mechanism and: are less susceptible to cold stress in comparison to creeping bentgrass.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.437-442
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• 2015

Studies to estimate seed longevity and dormancy of creeping bentgrass (Agrostis stolonifera L.) were conducted from 2000 to 2005 at Corvallis and Hermiston, Oregon. Seeds from three transgenic glyphosate resistant creeping bentgrass lines, 48-10, 48-13, and ASR368, and one non-transgenic glyphosate susceptible line, SR1020, were used. Creeping bentgrass seeds were buried at 3, 18 and 31 cm in 2000 and removed 6, 12, 18, 24, and 51 months later. Soil type and climatic conditions were different at the two locations. At Corvallis, the soil was a Malabon silty clay loam, and the winters wet and mild. The soil at Hermiston was an Adkins fine sandy loam, and winters drier and colder. Seeds of all creeping bentgrass lines deteriorated faster at Corvallis than at Hermiston. The estimated half-lives of creeping bentgrass lines buried at Corvallis were 8.4 to 20.2 months, while those buried at Hermiston were 8.4 to 37.7 months. At both sites, seeds of the glyphosate resistant lines, 48-10 and 48-13, deteriorated faster than the susceptible line, SR1020. However, seed deterioration in the resistant line, ASR368, was slower than all other creeping bentgrass lines. Based on the germination test, exhumed intact seeds at Corvallis were more dormant than those at Hermiston. If buried, it could be expected that viable creeping bentgrass seeds will persist more than 4 years after the seeds are introduced to a site, but environmental conditions can influence both seed longevity and dormancy.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.177-183
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• 2011

The susceptibility of cultivars of three bentgrass species (creeping, colonial, and velvet bentgrass) was evaluated on detached leaves assays with pink snow mold 9 isolates caused by Microdochum nivale in Petri dishes and whole plants under controlled conditions. The pink snow mold isolates obtained from infected turfgrasses on golf courses in Wisconsin were tested on response of fungicides and temperature. Detached leaf assay and susceptibility of bentgrass cultivars were evaluated with potted adult seeding during 80 days. Nine isolates were susceptible to two fungicides and were significantly different among isolates. Mycelial growth was varied in response of temperatures among isolates. There were significant differences in development and colonization of the fungus on detached leaf assay among bentgrass species include culvitars. There were significant differences on whole plants in disease severities among the three bentgrass species, particularly between tetraploids (creeping and colonial) and diploid (velvet) species, and among cultivars within each species, indicating that there are varying levels of susceptibility in species and cultivars to M. nivale. This study could be applied to evaluate the susceptibility of bentgrass to pink snow mold and also to predict a prospective evaluation of bentgrass cultivars to pink snow mold in fields in a breeding program.