• Asian Journal of Turfgrass Science
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• v.12 no.4
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• pp.189-194
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• 1998

The effect of proline, glutamine, aspartic acid and their combinations on callus induction and embriogenic callus formation from 3 creeping bentgrass (Agrostis palustris) cv. Regent, Mariner, Cato and 1 colonial bentgrass (Agrostis tenuis) cv. Tiger was estimated in both light and dark condition. The addition of amino acids to the growth medium did not have a significant stimulatory effect on the induction of embryogenic callus, instead, they were inhibitory, particularly at higher concentration (40 mM). But supplement of amino acids at lower concentrations (5 or 10mM) to basal medium was beneficial in inhibiting the formation of hairy outgrowth on the surface of embryogenic callus.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.199-206
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• 1995

This study is aimed to clarify on the influence of cultivated conditions and fungicides on development of Rhizoetonia diseases of zoysiagrass and creeping bentgrass and results are as follows. Infection rates of disease were observed more serious when inoculum amounts were higher than low. Effects of the watering intervals on the severity of disease with artificial inoculating conditions, infection rates were higher when two days watering interval for creeping bentgrass and one day interval for zoysiagrass. Disease severity of creeping bentgrass incited by Rhizoetonia solani AG 1 (1A) was grater under conditions of double amounts of nitrogen fertilization. A posi- tive correlation was founded between the pH and disease development. The pots with pH 5 and 8 were significantly more diseased grass than those in which the pH was in 6.5. Mepronil and myclobutanil were extremely effective against brown patch of creeping bentgrass and large patch of zoysiagrass and followed by capro, and tebeonazole. Fenari was inferior effect to both diseases.

• Proceedings of the Turfgrass Society of Korea Conference
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• 2004.01a
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• pp.24-31
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• 2004

This experiment was carried out to study an effect of liquid fertilizer contained amino acids(LFcAA) on the growth of Bentgrass(Agrostis palustris Huds. penncross) and the change of soil chemicals characteristics. In tested soil, the utilization rate of nitrogen in treatment was more than control. Fresh weight, dry weight and concentration of T-N, Mg and chlorophyll were increased in grass treated LFcAA. These results suggested that treatment of LFcAA was promoted utilization of nitrogen in soil and growth of bentgrass.

• Rapid Communication in Photoscience
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• v.3 no.2
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• pp.28-31
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• 2014

Loss of chlorophyll is the visible symptom of leaf senescence and staygreen refers to the delayed leaf senescence in plants. The staygreen gene (SGR) in rice (Oryza sativa L.) has been identified as its mutation maintains greenness during leaf senescence, and encodes a chloroplast protein required for the initiation of chlorophyll breakdown in plants. In this study, we isolated a rice SGR-homologous gene in creeping bentgrass (Agrostis stolonifera L.), and transgenic creeping bentgrass plants were obtained by introducing pCAMBIA3301 vector harboring antisense SGR gene under control of the senescence-specific SAG12 promoter. Transgenic plants were selected by herbicide resistance assays and genomic integration of the transgenes was confirmed by PCR analysis. Subsequent analyses demonstrated the staygreen phenotype of the transgenic creeping bentgrass plants with decreased chlorophyll loss during leaf senescence. These results suggest that the antisense SGR expression in creeping bentgrass delays leaf senescence, which provides a way to develop genetically engineered turfgrass varieties with the commercially useful staygreen trait.

• Asian Journal of Turfgrass Science
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• v.11 no.2
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• pp.97-104
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• 1997

The objective of this study was to observe the differences in growth of creeping bentgrass turf to 'polymer coated urea fertilizer' and 'uncoated urea fertilizer', and to analyze durability of fertilizer effect with the 'polymer coated urea'. The experiment was initiated on June 3, 1996, at the Iowa State University Horticulture Research Station, north of Ames, Iowa. The experiment was conducted on an area of 'Penneagle' Creeping bentgrass(Agrostis palustris) maintained at fair-'way mowing height (1.3cm). The study was repeated at the same arrangement beginning on July 25, 1996. Visual quality data, clipping fresh and dry weight, and nitrogen(N) content in the clippings were taken weekly. Quality of the turf increased with increasing N rate. While quality ratings were higher for turf receiving polymer coated urea than for turf receiving uncoated urea at several times following treatment, but not significant. Fresh and dry clipping weights were quite variable during the trial. Visual quality rating and clipping yields improved with increasing rates of N but these differences were not statically significant between polymer coated and uncoated urea treatment. The durability of fertilizer efficiency in polymer coated urea was not last longer compare with uncoated urea from two weeks after treatment. Higher rates of N application increased the concentration of N in tissue but no significant differences between turf plots receiving polymer coated and uncoated urea. Key words: Polymer coated urea, Creeping bentgrass, Fertilizer, Turfgrass.

• Journal of Environmental Science International
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• v.31 no.4
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• pp.311-318
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• 2022

In this study, we analyzed the relationships between weather factors and photosystem II activity (F_v/F_m), as a measure of photochemical efficiency, in three cool-season turfgrasses commonly planted on golf courses in Jeju, South Korea: perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), and creeping bentgrass (Agrostis palustris Huds.). In all three turfgrasses, F_v/F_m was higher during late summer than during early summer. However, in late summer, F_v/F_m was significantly lower in perennial ryegrass than in the other two species. In early summer, F_v/F_m in perennial ryegrass and Kentucky bluegrass was positively correlated with mean low temperature and extreme minimum temperature, whereas, in late summer, this parameter in Kentucky bluegrass and creeping bentgrass was positively correlated with relative humidity, and in creeping bentgrass was negatively correlated with mean high temperature, mean low temperature, and extreme maximum temperature. These results indicate that raising low temperatures is favorable for perennial ryegrass and Kentucky bluegrass in early summer, whereas, in late summer, the lowering of high temperatures proves to be beneficial for creeping bentgrass, and raising relative humidity is conducive to the growth of Kentucky bluegrass and creeping bentgrass. These findings will contribute to improving the selection and management of turfgrasses on golf courses and sports fields.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.64-68
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• 2012

Creeping bentgrass (Agrostis stolonifera L.) is one of the highest maintained turfgrass but often problematic especially for Kentucky bluegrass fairway. Mesotrione is one of selective herbicide that is firstly registered for corn (Zea mays L.) and provides preemergence and postemergence control of broadleaf and annual grassy weeds. Although mesotrione is effective to eradicate area contaminated by creeping bentgrass, protracted time is required to recover damaged area by rhizome extension of Kentucky bluegrass. Overseeding is typically used to fill bare or damaged areas using appropriate turf species to create a uniform turfgrass surface. The objectives of this study were to evaluate mesotrione and seeding rate effects to recover Kentucky bluegrass contaminated by creeping bentgrass. Six treatments consisted of three mesotrione rates and two Kentucky bluegrass seeding rates. The mesotrione rate were 0, 0.05 and 0.10 m $ml^{-2}$. Two seeding rate of to Kentucky bluegrass 'Midnight' were 15 and 30 g $m^{-2}$. Mesotrione application and Kentucky bluegrass overseeding at the same time is helpful to damage creeping bentgrass but not for establishment of Kentucky bluegrass to refill damaged area. To maximize mesotrione effects, temperature above $20^{\circ}C$ would be recommended based on this study.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.6-12
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• 2009

Snow molds are the most important winter diseases of turfgrass in the United States and Canada. Eight isolates of three snow mold fungal species (three isolates of Typhula ishikariensis, three of T. incarnata, and two of Microdochium nivale) were collected from infected turfgrasses on golf courses. The isolates were evaluated for their relative aggressiveness on three cultivars (L-93, Penncross, and Providence) of creeping bentgrass (Agrostis palustris) under the same controlled conditions. Four plant ages (15, 19, 23 and 27 week-old plants from germination to inoculation) were evaluated for their susceptibility to the three pathogens and for the recovery of the plants. Regardless of age or cultivar of the host plant, M. nivale was found to be more aggressive and faster to infect and colonize than Typhula species. After three weeks recovery, M. nivale-inoculated plants showed higher disease severity than plants inoculated with the two Typhula species. Plants infected by Typhula species displayed no significant difference in disease severity. As creeping bentgrass plants get older, the severity of disease caused by three snow molds gradually decreases. This effect was observed in all cultivars tested, suggesting expression of age-related resistance as the bentgrass plants matured.

• Asian Journal of Turfgrass Science
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• v.17 no.4
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• pp.147-154
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• 2003

This experiment was carried out to study an effect of liquid fertilizer contained amino acids(LFcAA) on the growth of bentgrass(Agrostis palustris Huds. penncross) and the change of soil chemicals characteristics. The utilization of nitrogen in soil was increased more 70.6∼90.1％ in the treatment of LFcAA than in control. Fresh weight, dry weight and concentration of T-N, Mg and chlorophyll were increased in grass treated LFcAA. These results suggested that treatment of LFcAA was promoted utilization of nitrogen in soil and growth of bentgrass.

• Asian Journal of Turfgrass Science
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• v.14 no.1
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• pp.257-262
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• 2000

This study was conducted on ten golf courses in the vicinity of Yongin city to find out the kinds of algae and factors affecting algae development on creeping bentgrass greens. 1. Serious algae contamination was observed on almost of creeping bentgrass greens after and before rainy season. 2. There were ten kinds of algae occurred on creeping bentgrass greens, most of which were Oscillatoria spp. (bluegreen algae) 3. The fact that the same kind of algae inhabiting in the pond was observed on greens indicated that greens were easily contaminated by algae in case of greens watered with the pond. 4. This study showed that the main factor affecting algae contamination on greens was not high total nitrogen and phosphorus contents in the green soil, but pond watering.