• Journal of Life Science
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• v.18 no.8
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• pp.1096-1105
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• 2008

This study was carried out to identify the optimum condition for priming, as a series of experiments for the enhancement of germination percentage and germination synchronization in cool-season turfgrass seeds. The optimum priming conditions to maximize the germinability in both Kentucky bluegrass and Tall fescue was a 1 day treatment of 100 mM $K_3PO_4$ at $25^{\circ}C$. The seeds treated with the optimum priming condition enhanced the germinability compared to control, and shortened the time for germination with reduced $T_{50}$ and mean daily germination (MDG). However, as the concentration and treatment period of NaOH or KOH increased, significantly decrease in germination percentage was observed. Germination percentage in Creeping bentgrass and Bentgrass was below 10%, regardless of priming treatment. However, the priming treatment with 200 mM $KNO_3$ for three days improved the germination up to 6%, which was not a statistically significant level. The most effective priming period for Kentucky bluegrass and Tall fescue was one day treatment, but the germinability was suppressed as the treatment period was extended until six days. For priming chemical treatment, germinability was improved with the concentration of 100 mM, while it was reduced at higher concentrations of 200 mM and 300 mM.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.173-185
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• 1995

Hydroseeding technique is a very popular method of revegetating slope areas through the control of soil erosion and stability by seeding grasses. This study was conducted to select turfgrass species and cultivars for hydroseeding. Experiment plots were established on various soil types and environmental conditions at Singar-Ansan high-way construction site. The investigation was designed in three cutting, one back-filling and other three spare sites with various seed mixtures. Results indicated that combinations of seed mixtures influenced seed germination and rates of surface cover. In a view of long term, vegetation shifts should be influenced by characters of slopes and micro-climate conditions. Hydroseeding did not show good results on rocky slope areas. Revegetation was only going on where there had soil. The combination of seed mixture with a higher rate of perennial ryegrass had relatively good revegetation with faster germination and seedling growth. Improved turf-type tall fescue Arid ⓡ and Falcon ⓡ seemed to have good environ-mental adaptation and drought tolerance. Wild or old type cultivars showed relatively slow green-up in spring and growth rates at the next year of seeding. For the harmonious landscaping with surrounding area, the combination of native grass mixture with cool-season grasses had good results. Slow and low revegetation rate at hack-filling site seemed to be caused by the poor development of capillary tubes in sub-soil. It was shown that a high correlation between seed germination and revegetation rate, and between three-month later coverage rate and final rate. The evaluation of coverage rate after three month seems to he acceptable to decide the accomplishment of hydroseeding results on rode side slopes.

• The Plant Pathology Journal
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• v.40 no.3
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• pp.272-281
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• 2024

Field surveys were conducted to assess the occurrence and diversity of plant-parasitic nematodes (PPNs) in golf courses and athletic fields across Maryland, USA, during 2022 and 2023. A total of 28 golf courses and ten athletic fields were surveyed, revealing the prevalence and abundance of 13 PPNs taxa in the region. Criconemoides was identified as the most prevalent (94.9%) and Tylenchorhynchus as the most abundant (2.3) across all samples. Central golf courses (west side of the Chesapeake Bay) exhibited a high prevalence of Criconemoides and Tylenchorhynchus, while Eastern Shore golf courses and athletic fields displayed a higher prevalence of Helicotylenchus and Criconemoides. Further, Belonolaimus longicaudatus was reported for the first time from turfgrass in Maryland, raising concerns due to its potential to cause severe damage on both cool- and warm-season turfgrass. Biodiversity analysis indicated that richness (R²) was higher in athletic fields, while diversity (H') and evenness (J') were significantly greater in golf courses. This study provides baseline information for monitoring PPNs distribution in Maryland and also for the development of effective nematode management approaches in turfgrass ecosystems.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.107-118
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• 2006

This study was carried out to introduce a couple of commercialized patented technologies in the area of turfgrass production. All sod production related patents in Korea during the period from Dec. 20, 1948 to Dec. 30, 2005 were reviewed. Details of two patents (patent No. 0434389 and 0478194) were included. The results are summarized as follows: 1. One of the domestic patents on sod production was the technique using natural and plastic films. Information on topsoil mixtures was also reviewed form foreign patents. 2. Patented multi-purpose sowing equipment can evenly mix soil, sand, fertilizer and other soil conditioners with seed, stolen and rhizome of turfgrass. 3. Patent on cool-season turfgrass sod production provide topsoil mixture combination and mixing ratio for sports field, landscape area and roof garden.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.67-76
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• 2017

The study was initiated to evaluate the effects of overseeding warm-season grass (Zoysia japonica Steud.) with cool-season grasses (CSG) on turfgrass density, uniformity and tiller appearance and to determine turfgrass species and seeding rate applicable for a practical use. Treatments were comprised of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), tall fescue (TF, Festuca arundinacea Schreb.) and their mixtures. Overall turfgrass density and uniformity were much better with the overseeded treatments over the control. In early stage after overseeding, the greater the PR in treatments, the greater the turfgrass density and uniformity. But the higher the KB, the lower the density and uniformity. From the middle-stage evaluation, however, we observed the opposite results as compared with early-stage findings. Accordingly, the KB was highest in turfgrass density and uniformity, while the PR lowest. In regards of mixtures, both turfgrass density and uniformity were better with increased KB and decreased PR in overseeding rates. As for a medium-quality mixtures of Korean lawngrass with CSG, it would be the best choice to apply with KB at $50g\;m^{-2}$ and equal combination of KB, PR and TF by 1/3 in mixing at $75g\;m^{-2}$ in terms of sustainable density and uniformity.

• Asian Journal of Turfgrass Science
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• v.15 no.2
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• pp.87-104
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• 2001

This Study was carried out to investigate on the environmental effects of golf courses and to find a solution to the negative effects in Korea. The results were ai follows. 1. There were 152 golf courses opened in December 2000. 113 golf courses were member-ship and 39 golf courses were public. Users (golfer) were over 12,000,000 in 2000. 2. Total area of golf courses was 0.8% as compared with total area of farmland in 1999. Total amount of agricultural chemicals used in golf courses was 0.3% of total amount of agricultural chemicals used in Korea. The remaining amount of agricultural chemicals in golf courses tested were almost below the permitted limits. 3. Recently, total amount of fertilizers in green decreased 5~7g/$m^2$/year as compared with the recommended. 4. The control by antagonistic microorganisms and the fertilizing of the organic matter or the organic fertilizer were effective to decrease the amount of agricultural chemicals used. To success the control of microorganisms, active antagonistic microorganisms had to be applied over the recommended dose eve교day. Though fertilizing of organic fertilizer, slow release fertilizer, was effective to suppress dollar spot, necrotic ring spot. fungicides were required as a supplementary means when disease symptom was very heavy. 5. Zoysiagrass was fertilized intensively from May to August. Cool-season grasses were fertilized intensively from March to May and September to October. The fall fertilizing of Zoysiagrass was carried out to the begining of October. The fall fertilizing of cool-season grasses were carried out to the end of November or the begining of December. The fertilizing amount of Zoysiagrass was 10g/$m^2$/year. The fertilizing amount of bentgrass was 25~27g/$m^2$/year.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.253-260
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• 1995

This study is aimed to understand the effects of temperature, light and GA soaking treatment on the seed germination of perennial ryegrass 'Dandy', creeping hentgrass 'Penlinks', tall fescue 'Arid' and Kentucky hluegrass 'Nasaw'. These experiments are carried in vitro, and their results obtained are summarized as the followings ; The optimum temperature for seed germination of perennial ryegrass 'Dandy' was found to he ranged at 20~30$^{\circ}C$, and the optimum temperature for germination of creeping bentgrass 'Penlinks', tall fescue 'Arid' and kentucky bluegrass 'Nasaw' seeds was found to be ranged at 20~25$^{\circ}C$, whereas the germination percentage under the below or above temperature of this range decreased. The germination of perennial ryegrass 'Dandy' and tall fescue 'Arid' seeds showed no effect on light, and while the germination percentage of creeping hentgrass 'Penlinks' increased more highly under the dark condition than under the light condition. The germination percentage decreased according to the higher temperature. The germination of Kentucky bluegrass 'Nasaw' seeds increased more highly under the dark condition than under the light condition at 20~25$^{\circ}C$, whereas the germination percentage under the dark condition at 15$^{\circ}C$ and 30$^{\circ}C$ decreased. In case of GA soaking treatment of seeds, all the cool season turfgrasses tested showed their own promoting effects on seed germination. The early germination of tall fescue 'Arid' was good without the soaking times. Creeping bentgrass 'Penlinks' and perennial ryegrass 'Dandy' had re-spectively the highest germination percentage at 10min and 1hr soaking treatment, and the longer the soaking time, the lesser the germination percentage. Kentucky bluegrass 'Nasaw' obtained the best results at 24has soaking treatment, and the longer the soaking time, the better the ger-mination percentage.

• Weed & Turfgrass Science
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• v.3 no.2
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• pp.121-129
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• 2014

We investigated turfgrass diseases and inoculum density at nationwide turfgrass cultivation sites in year of 2013. Occurrences of large patch and rust disease appeared in September. Brown patch recorded in September to October at Namhea and Pythium blight disease occurred outbreaks in early July at Namhea site. Some sites in Namhea damaged 3% area of total cultivation field by Sclerotinia homoeocarp. In Daepyeong (Gyeongnam), Fairy ring and large patch were recorded. Severe takeall and fairy ring have been observed in Gochang-si. Multi-site in Cheongju-si, brown patch was observed in pandemic level. Interesting enough, a cool-season turfgrass cultivate sites in Pyeongtaek-si brown patch, leaf blast, summer patch, and Curvularia leaf spot were investigated during the surveys period. Inoculum densities (Rhizoctonia spp.) at turfgrass cultivations sites were increased as cumulatively in all survey sites. The investigation result indicated that the disease occurrence and pathogens are similar as diseases in golf courses.

• Asian Journal of Turfgrass Science
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• v.5 no.1
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• pp.23-32
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• 1991

The purpose of this study was to determine the vegetative growth of two cool season turfgrasses during summer season in Korea. Ten respective cultivars of Kentucky bluegrass [Poapratensis L.] and perennial ryegrass [Lolium perenne L.] were exposed to unshaded, 30% and 60% shade for 4odays. First mowing height was 7cm, and then clippings were harvested every ten days at the same height. Shading increased the total length of clippings of all cultivars of two turfgrasses, but fresh and dry weight were significantly decreased. The highest shoot length obtained at 30% shade in Kentucky bluegrass and at 60% shade in perennial ryegrass. 'Rugky', 'Sydsport', 'Wabash' and 'Baron' of Kentucky bluegrass and 'Repel', 'Omega II', 'Ovation', 'Linn', 'Bell' and 'Manhattan' of perennial ryegrass showed relatively high tolerance to shade. Especially, in 'Citation II' perennial ryegrass, fresh and dry weight were increased by 30% shade. The number of tillers generally decreased with increasing shade. In 30% shade, 'Midnight' Kentucky bluegrass and 'Omega II' perennial ryegrass were least reduced and 'Baron' Kentucky bluegrass and 'Pennant' perennial ryegrass were most reduced. The cultivars of lower growth habit in full sunlight showed shade tolerance compared to those of higher growth habit.

• Asian Journal of Turfgrass Science
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• v.18 no.3
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• pp.129-139
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• 2004

This study conducted to find out the best way to prolong green period of Zoysiagrass and Cool-season grass from 1999 to 2001 in Korea. Treatments were control, vinyl, black shade net, green shade net, black shade net+vinyl, green shade net+vinyl, vinyl+black shade net, and vinyl+green shade net for Zoysiagrass. For cool-season grass, treatments were control, non-punched vinyl and punched vinyl. Data on temperature, light intensity, humidity, leaf color and chlorophyll were collected. Plot size was 2 by 2 and the experiment was conducted using completely randomized design with three replication. Zoysiagrass Green period of Zoysiagrass depended on temperature and light intensity than humidity. Effective method of prolongation of green period in Zoysiagrass was to covered it with vinyl during early October to early November, and then using vinyl+black shade net from end of November. Cool-season grass Effective method of prolongation of green period in Cool-season grass was by covering it with vinyl during mid-November to mid-December, and then using vinyl+black shade net from end of December.