• Weed & Turfgrass Science
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• v.4 no.3
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• pp.151-158
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• 2015

This study was conducted to establish the effective weed management methods in rice field simultaneously dominated by the herbicide resistant Echinochloa oryzicola, Monochoria vaginalis and Scirpus juncoides. Herbicides registered for use before transplanting, oxadiazon 12% EC, pyrazolate 36% SC, pretilachlor 14% EC and thiobencarb 50% EC were effective until 0.5 leaf stage of herbicide resistant Echinochloa oryzoides. Herbicides registered for use after transplanting, fentrazamide 1% GR and mefenacet 18% SC were effective until 2 leaf stage of herbicide resistant Echinochloa oryzicola and triafamone 0.98% SC was possible to control up to 4 leaf stage. HPPD inhibitors, benzobicyclon, mesotrione and tefuryltrione SC, were simultaneously effective to SU herbicide-resistant Monochoria vaginalis and Scirpus juncoides. Herbicides registered for use before transplanting, benzobicyclon + oxadiargyl EC out of the tested herbicide was most effective in rice field simultaneously dominated by the herbicide resistant Echinochloa oryzicola, Monochoria vaginalis and Scirpus juncoides. Its effectiveness rises in proportion to flooding duration. Mazosulfuron GR, a herbicides registered for use after transplanting was most effective without phytotoxicity until 60 days after transplanting in rice field simultaneously dominated by the herbicide resistant Echinochloa oryzicola.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.49-57
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• 2015

This research was initiated to analyze the periods of spring green-up and winter leaf discoloration of three ornamental grasses which have potential to be widely used with seed propagation. Two native grasses of Arundinella (Arundinella hirta var. ciliata Koidz), fountaingrass (Pennisetum alopecuroides (L.) Spreng), and switchgrass (Panicum virgatum L.) was tested. Spring green-up were evaluated after one year growth from seed propagation on April 1, 2009. Arundinella started with quick pick of spring green-up during $13^{th}$ to $20^{th}$ of May. Fountaingrass and switchgrass showed relatively slow picks of green-up during $20^{th}$ to $27^{th}$ of May. However, winter leaf discoloration started on swtichgrass and fountaingrass but Arundinella terminated relatively slowly. Swtichgrass showed the pick discoloration during $8^{th}$ to $15^{th}$ of October from the bottom to top parts of the plant. Fountaingrass showed the pick winter discoloration started from bottom to top parts during the $22^{nd}$ to $29^{th}$ of October. However, Arundinella showed relatively slow discoloration from upper to bottom parts during October $29^{th}$ to November $5^{th}$. Arundinella showed a relatively higher ornamental value with 125 days of the complete green period compared than fountaingrass and swtichgrass which maintained approximately 105 days of green period.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.262-267
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• 2015

In order to establish the efficient sod production and soil management, there is a need to perform research on the growing condition of zoysiagrass on soil environments. With an attempt to identify the growth of zoysiagrass and the chemical characteristics of soil according to different growing seasons, this study was carried out in separate areas where zoysiagrass has been grown for 1 year, 10 years, 20 years, and 30 years. As the growing season became longer, bulk density of the soil was increased, porosity and gaseous phase were decreased. The level of pH was highest in the area where zoysiagrass has been produced for 30 years, whereas total nitrogen and organic matters were found to be the greatest in where zoysiagrass has been produced for 1 year. Accordingly, the chemical properties of soil were deteriorated more in the area with continuous cropping than in the area with 1 year of cropping. As the time period of producing zoysiagrass became longer, growth of shoot and root were decreased. In this study, it is required to produce zoysiagrass through soil improvement in areas that have been used for production for over 10 years.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.26-34
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• 2015

Korean Poaceae includes approximately 80 species of the agricultural weeds. Precise species identification is the first step for more effective weed management in the agricultural fields. However, the identification of species in Poaceae is not easy without the assistance of taxonomists or identification experts although they are relatively easy to distinguish from the plants of the other family by the unique characteristics of caryopsis. Thus, DNA barcode was suggested as an alternative powerful technique for species identification by using short sections of DNA from a specific region of the genome. Two standard barcode markers of vascular plants, chloroplast rbcL and matK, and a supplementary nuclear ribosomal Internal Transcribed Spacer (ITS) region were used for barcode of major Korean Poaceae weeds, 403 individuals of 84 taxa. All the barcode markers revealed a good level of sequencing success with the lowest 73.7% for matK and the highest 88.8% for rbcL. The barcode sequences were deposited to the National Center for Biotechnology Information (NCBI) database for public use. Combined matK and ITS showed very high resolving power with 92.9%. Besides the identification of weeds for weed managment, the generated DNA barcode data could be used for many other applications such as rapid biodiversity assessment and conservation prioritization.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.243-248
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• 2015

This study was conducted to investigate the ability for weed control of the shoot extract of sorghum (Sorghum bicolor (L.) Moench) and developing a sustainable weed management in organic farming. When the dried shoot powder was mixed with soil and treated with 2 cm above the soil surface, the germination for Echinochloa crus-galli, Digitaria cilialis, Abutilon theophrasti and Amaranthus retroflexus was inhibited maxium 40%. The growth inhibition of germinated seedlings in the A. theophrasti and A. retroflexus was maxium 30% while it was less than 30% in the E. crus-galli and D. cilialis. Shoot extracts at rates above $25mg\;ml^{-1}$ was effective to inhibit germination of D. cilialis, A. theophrasti and A. retroflexus. The shoot extract concentration required for 50% of germination inhibition was $60mg\;ml^{-1}$ in the E. crus-galli, while it was less than $10mg\;ml^{-1}$ in the D. cilialis, A. theophrasti and A. retroflexus. For the foliar application, 11 adjuvants were tested at 0.5% and DOS70, TM15 and TDE7 were most effective adjuvants for the shoot extracts. DOS70 was most effective and provided up to 60% of weed control efficacy for the tested four weed species. Though herbicidal efficacy of sorghum shoot was not enough to give a proper weed control, it can be expected that long term use of sorghum shoots can provide gradual decrease in weed seeds and weed density.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.44-48
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• 2015

This study was conducted to evaluate the efficacy of weed control and phytotoxicity of oxyfluorfen using a transgenic rice line (CPPO06 event) resistant to protoporphyrinogen oxidase (Protox) inhibiting herbicides in the direct-seeding flooded rice. Five annual weeds including Echinochloa oryzoides and two perennial weeds were occurred in the test field. Oxyfluorfen at 120 g a.i. $ha^{-1}$ in the application timing of two days before sowing and 0 and five days after sowing showed more than 90% weed control value except for Juglans mandshurica. Total weed control value was more than 95% in any application timing indicating a highly effective herbicide in the direct-seeding flooded rice. When compared with untreated control, no visual injuries were detected at single and double dosage of oxyfluorfen. The agronomic characteristics and yield components of CPPO06 event was reasonable in any time of application in this study. Based on these data, oxyfluorfen application before and after sowing can be applied to provide effective weed management in the direct-seeding flooded field.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.49-78
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• 1998

Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

• Weed & Turfgrass Science
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• v.5 no.1
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• pp.10-16
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• 2016

Proper actions such as discard, return or manufacturing should be taken to imported plants contaminated with quarantine weeds. Heat-treatment has been used as a processing method in many countries such as U.S., Australia, Canada as well as Korea. This study was carried to find appropriate heat-treatment methods for devitalizing dodder seeds mixed with plant seeds. Two species of dodder seeds and six imported seeds were treated for 1, 5, 10, 15, 30, 45 minutes or 1, 2, 4, 5, 6, 8 hours at the temperatures of $75^{\circ}C$, $80^{\circ}C$, $85^{\circ}C$, $90^{\circ}C$, $95^{\circ}C$, $100^{\circ}C$ and $120^{\circ}C$. According to the study, dodder seeds were devitalized at the conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes, $95^{\circ}C$ and $100^{\circ}C$ for 15 minutes, $110^{\circ}C$ for 10 minutes and $120^{\circ}C$ for 5 minutes. Meanwhile, seed vigours of Cosmos bipinnatus and Callistephus chinensis had no difference when compared with untreated control at the heat-treatment conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes.

• Weed & Turfgrass Science
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• v.5 no.3
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• pp.177-180
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• 2016

This study was conducted to identify problematic weed species in grape orchard fields to establish basic information for suitable weed control. Surveys of weed species occurring in grape orchards were conducted in Chungnam province including Daejeon and Sejong of Korea from April to June and from September to October in 2015. From the surveys, 50 weed species belonging to 23 families (33 annuals and 17 perennials) were identified. In the first survey, the most dominant weed species by the importance values was Poa annua (7.07) followed by Echinochloa crus-galli (6.56), Digitaria ciliaris (6.43) and Capsella bursapastoris (5.63). In the second survey, Rorippa palustris (9.59), Eclipta alba (9.13), Digitaria ciliaris (7.68) and Poa annua (7.68) were dominant. Different weed species and dominance patterns were detected according to weed control methods in the grape orchards. Seven weed species belonging to six families were identified in the field in which herbicides were being used as a weed control method. However, most weed species (21 species belonging to 9 families) were occurred in the mowing + tillage fields. These surveys provide information about seasonal variations of weeds species occurred in grape orchards and impact of different weed control methods on the weed occurrence.

• Weed & Turfgrass Science
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• v.5 no.3
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• pp.105-110
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• 2016

This paper provides the current status of weed science and prospects for the development of weed science based on the research trends presented at the 7th International Weed Science Conference in 2016. Approximately 520 researchers from 59 countries, including Korea, participated in the conference and presented 625 papers in nine research areas. Major research topics were herbicide resistance, weed ecology, weed management in agricultural and non-agricultural lands, herbicide spray technology, and non-chemical weed control. Studies on herbicide resistance presented more than 30% of all papers presented. Particularly, resistance to non-selective herbicides, such as glyphosate and glufosinate-ammonium, and non-target sites of resistance mechanisms were the main subjects of the herbicide resistance research area. Moreover, the conference focused on research concerning herbicide resistant weeds of staple crops of the world (corn, wheat, and rice). Arylex was introduced as a new compound which has a mode of herbicidal action similar to synthetic auxin. Three compounds being developed as HPPD inhibitors were studied for ways to reduce their toxicity and tested as mixed with safeners. Additionally, parasitic weeds, which are not native to Korea, are an expanding research subject in the world. Although 45 years have passed since the first report of herbicide resistance in 1970, herbicide resistance remains a serious problem in most intensive cropping systems of the world and will continue to be a major area of study in the future.