• Korean Journal of Weed Science
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• v.7 no.2
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• pp.179-185
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• 1987

Laboratory studies were conducted to evaluate safening effect of CGA 123'407 (4,6-dichloro-2-phenyl-pyrimidine) against pretilachlor, butachlor, and benthiocarb in rice plants. Butachlor and benthiocarb at 50 ppm or higher concentrations significantly inhibited rice growth and pretilachlor gradually inhibited growth of rice plants with increase in concentration starting from 0.5 ppm. CGA 123'407 at 0.1 ppm or higher concentrations was effective in reducing injury of rice plants when butachlor and benthiocarb were applied at rate of 10 ppm. Rice injury from pretilachlor at 10 ppm was also reduced by addition of CGA 123'407 at 0.25 ppm or higher concentrations Herbicidal activity of pretilachlor, butachlor, and benthiocarb was not affected by mixture treatments of CGA 123'407.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.330-339
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• 2011

This study was conducted to determine the herbicidal activity of herbicidal substances and identify them in bulbs of Lycoris flavescens. Methanol extract was purified by a series of chromatographic techniques including silica gel column chromatography, preparative TLC, and HPLC. The final HPLC gave two active fractions and two herbicidal substances were obtained. By GC/MS analysis, one was identified as galanthine (galanthan-1-ol) and the other was identified as montanine ($O^2$-methyl pancracine), an isoquinoline alkaloid. Montanine showed nearly 100% of growth inhibition on the shoot and root of barnyardgrass (Echinochloa crusgalli) seedlings at $20{\mu}g\;mL^{-1}$ as compared with the control. Meanwhile, methanol extract of L. flavescens bulbs showed only about 3.1% and 8.3% of growth inhibition on the shoot and root of rice cultivar, Hwayeongbyeo seedlings at $1,000{\mu}g\;mL^{-1}$ as compared with the control, respectively.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.71-76
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• 2018

The purpose of this study is to suggest ways to improve development plan of the National Library of Korea, comparing development plan of the Library and strategic plans of national libraries in western countries, China and Japan. For this purpose, plans of national libraries in Korea and Overseas were collected and analyzed. And a rubric evaluation was applied to the case plans. The findings indicate that plan of the National Library of Korea is written for analyzing present problems, setting practical activity-centered detailed plans. On the other hand, plans of national libraries overseas present distinct mission and vision statement, and set up goals, objectives, concrete activities in the framework, which function as milestones for developing libraries. As a conclusion, this study suggests that the National Library of Korea need mission and vision statement, links among mission, vision, goals, objectives, activities, and ongoing library marketing. This study can contribute for the National Library of Korea to develop plan with the concept of strategic plan.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.199-207
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• 1988

The study was intended to know any relations between the rice tolerance to oxyfluorfen and varietal speciation in seed protein composition or any enzymatical allelies with or without chemical treatment. Rice varieties used were Chokoto, Aichiasahi, Agabyeo, IR 3941 and Tablei as the tolerant group, and Mushakdanti, Weld Pally, HP 1033, HP 857, and HP 907 as the susceptible, respectively. Electrophoretic methods used were SDS-PAGE for seed protein, 7% PAGE for isozymes (acid phosphatase and peroxidase from rice seedling) and changes in isoenzyme activity (malate dehydrogenase, peroxidase and esterase) as affected by oxyfluorfen treatment ($10^{-4}M$) was also studied. The results are summarized as follows. -Among 19 bands separated in seed proteins, two different rice groups selected in terms of tolerance were clustered in dissimilarity. This was based on 2 facts in that G band was not present in susceptible varieties and that less activity of H, N, O, P, Q, Rand S band was shown. -Among 4 bands separated in acid phosphatase, the presence of (band and lower activity of B band was specific for tolerant varieties. For 4 minor bands separated in peroxidase, the tolerant varieties had no activity in B band and higher activity in A, C, D bands. -Time-course study of isozymes as affected by $10^{-4}M$ oxyfluorfen showed that Chokoto, the tolerant varieties, had little activity in A band and consistently higher activities in Band C bands for malate dehydrogenase. For 5 bands separated in peroxidase, B band was not found in Chokoto while A, C, D, and E bands were consistently present. Esterase was separated into about 4 bands in which Chokoto had maintained higher activities in A, C and D bands.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.171-178
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• 1998

Growth response and acetolactate synthase(ALS) activity were examined to determine the resistance of corn cultivars to primisulfuron when primisulfuron and/ or insecticide Terbufos were applied. Pioneer 3571 IR showed resistance to primisulfuron regardless of Terbufos treatment, but Pioneer 3571 was greatly injured with primisulfuron plus Terbufos treatment. Suwon 118 was relatively tolerant to primisulfuron compared to Chalok 2, but crop injury was occurred at both cultivars by primisulfuron plus Terbufos treatment. ALS activity at Pioneer 3751 IR was very high in primisulfuron and/ or Terbufos treatment. Suwon 118 also showed higher ALS activity compared to Pioneer 3751 and Chalok 2, but ALS activities were greatly decreased by primisulfuron plus Terbufos treatment at Suwon 118 and Chalok 2. The $I_{50}$ concentration for 50% inhibition of the ALS enzyme was 10.0, 0.06, 7.75, and 0.04${\mu}M$ for Pioneer 3751 IR, Pioneer 3751, Suwon 118, and Chalok 2, respectively. Consequently, resistance of corn cultivars to primisulfuron was significantly related to ALS activity. Crop injury and lower ALS activity were recognized in susceptible corn cultivars by primisulfuron plus Terbufos treatment.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.30-37
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• 2013

The objective of this research was to understand herbicidal activity of essential oils isolated from leaves of pine (Pinus densiflora), nut pine (Pinus koraiensis), larch (Larix kaempferi) and khingan fir (Abies nephrolepsis) in Korea. In a seed bioassay, essential oils of nut pine, larch and khingan fir inhibited the growth of rapeseed (Brassica napus) seedlings by 50% at 4,766, 1,865, $5,934{\mu}g\;ml^{-1}$, respectively, however, that of pine did not show any herbicidal effect. In a green house experiment, fall panicum, Southern crabgrass, sorghum, barnyardgrass, quackgrass, black nightshade, Indian jointvetch, velvet leaf, and Japanese morningglory were controlled in 24 hours by the foliar application of 10% essential oils from pine, nut pine, larch and khingan fir. The treated plant parts showed burndown effect, however, new shoots appeared 3 days after treatment. Results of GC-MS analysis showed that essential oils from pine, nut pine, larch and khingan fir contained 16, 25, 25, and 16 compounds, respectively, with hydrocarbons, alcohols, ketones, and esters. The major compounds of the essential oils were 3-carene, bornyl acetate, camphene, limonene, ${\alpha}$-pinene, ${\beta}$-pinene and ${\beta}$-phellandrene.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.70-75
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• 2013

Seven medicinal plant extracts were tested for antifungal activities against six species of the major turfgrass pathogenic fungi (Colletotrichum graminicola, Pythium spp., Rhizoctonia cerealis, Rhizoctonia solani AG1-1, Rhizoctonia solani AG2-2, and Sclerotinia homoeocarpa) using paper disk diffusion method. Three medicinal plant extracts, including Pinus densiflora showed antifungal activities. In suppression of mycelium growth test, on medium adding P. densiflora extract showed that inhibition rate of mycelium growth were above 80% in 10 mg/10 ml concentration of the extract. The inhibition rate of Pythium spp. was 100% and C. graminicola was 84.3% in 10 mg/10 ml concentrations of P. densiflora extract, respectively. In particularly, the inhibition rate of Pythium spp. was 89.5% in 2 mg/10 ml concentrations of P. densiflora extract. As a result, P. densiflora extract showed high antifungal activity to Pythium spp. and C. graminicola of the turfgrass pathogen in in vitro test.

• Korean Journal of Weed Science
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• v.17 no.1
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• pp.66-70
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• 1997

LGC-40863(proposed common name ; pyribenzoxim), (benzophenone O-[2,6-bis[(4,6-dimethoxy-2-pyrimidinyl)oxy]benzoyl]oxime) is a new rice herbicide being developed by LG Chemical Ltd. The herbicide is highly selective between rice(Oryza sativa L.) and weeds including barnyardgrass (Echinochloa crus-galli(L.) P. Beauv.), and assumed to inhibit acetolactate synthase(ALS ; EC 4.1.3.18) because other structurally related herbicides inhibit the enzyme. To know inhibitory activity and the mode of inhibition of LGC-40863, $I_{50}$(concentration inhibiting ALS activity by 50%) and inhibition kinetics were investigated using ALS extracted from rice and barnyardgrass. $I_{50}$ values of LGC-40863 were 14 and 16mM in rice and barnyardgrass, respectively. In contrast to imazapyr(2-[4,5-dihydro-4-mythyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-pyridine-carboxylic acid) which showed an uncompetitive inhibition pattern, LGC-40863 was a noncompetitive inhibitor to ALS with respect to pyruvate similar to chlorsulfuron(2-chloro-N-((4-methoxy-6-methyl-l,3,5-triazin-2-yl) aminocarbonyl)benz-enesulfonamide) in both plants.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.263-272
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• 2012

The potential as natural herbicide of d-limonene natural agent was conducted on several weeds in a greenhouse and Sciyos angulatus in field condition. Herbicidal activity of foliar application at a concentration of 100 and 200 kg ai $ha^{-1}$ of d-limonene on seven weed species was completely killed in a greenhouse condition. Also, d-limonene at a concentration of 50 kg ai $ha^{-1}$ was completely killing on Abutilon theophrasti, Aeschynomene indica, Echinochloa crus-galli and Digitaria ciliaris 3 days after treatment. While pre-emergence treatment of d-limonene concentration of 12.5 to 200 kg ai $ha^{-1}$ showed not significant visible damages. Phytotoxic symptoms of d-limonene by foliar treatment were characterized by wilting and burn-down of leaves and stems followed by discoloration, finally, plant death. Crop selectivity at d-limonene concentration of 100 kg ai $ha^{-1}$ over to five main crops including Zea mays by foliar application was not at all. Field trial of foliar treatment with d-limonene 70 to 140 kg ai $ha^{-1}$ have effectively controled over 5~20 leaf stages of S. angulatus at the natural habitats. And herbicidal efficacy of foliar application on S. angulatus with carrier volume in field condition was increased with dose dependent manners. These results suggest that d-limonene is considered possible as herbicide, and may be further optimized for natural agent for environmental friendly natural herbicide.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.87-97
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• 2018

Turfgrass provides various beneficial effects to our societies such as recreation, aesthetic components, and other public service. Diseases in turfgrass is the major issue, which cause quality problems in golf courses, playgrounds, parks and cultivation areas, and tremendous cost is required to prevent the diseases. Research activity and investigation for turfgrass disease remain to be further attributed when compared to other crops in Korea. In this study, we present previously reported turfgrass diseases researches, especially caused by fungal pathogens, and review the history of turfgrass research activity in Korea to contribute future turfgrass research direction. Research papers were searched and analyzed using Korea Educational and Research Information Service (www.riss.kr). More than eighty papers presented turfgrass diseases and among the papers, 50% were published in Korean Journal of Turfgrass. Half of the papers reported turfgrass diseases control. Research articles about large patch disease were the majority (36%), followed dollar spot (18%), Pythium blight (10%) and Typhular blight (8%). Number of the first disease reports in Korea were total fifteen. Total 542 fungicides have been registered in Korea to prevent turfgrass diseases and most of the fungicides were for brown patch, rust, yellow patch, dollar spot, snow mold, summer patch, anthracnose, Pythium blight, powdery mildew and algae. And we will also need to conduct ecological studies on turf diseases and to develop control methods with improved efficacy and environmentally-friend sound. Researches on epidemiology of turfgrass diseases which deals with the incidence, distribution, and interactions with other factors will be also greatly favored for precise control prescription, timing of control and use of less pesticides.