• Korean Journal of Weed Science
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• v.14 no.1
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• pp.56-61
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• 1994

The cationic isoperoxidases were isolated from oat root tips which had been grown in treatment with $1{\times}10^{-4}$ M alachlor and purified about 30-fold by treatment with ethylalchol and ion exchange chromatography on DEAF-celluose and CM-sephadex medium. The oat root was found to contain three isoperoxidase. The major activity peak (B) represented 65% of the total isoperoxidase activity. After purification, the major peak of isoperoxidase was purified about 37-fold from the oat root. Analysis of the major peroxidase peak(column fraction 58-78) by SDS revealed a single band which corresponed to a molecular mass of 42.5 kD. In vitro, isoperoxidase activies were inhibited by IAA. Isoperoxidase(50 unit) significantly inhibited 70.2% of cell division in oat root and 54.2% of cell elongation in oat coleoptile as compared with control.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.199-208
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• 2015

This study was conducted to provide basic information for weed control by surveying the occurrence of weed species in upland crop fields in Gyeongnam province of Korea. The result of this survey, 55 weed species 21 families in barley fields, 56 weed species 22 families in garlic fields, 47 weed species 19 families in onion fields, 68 weed species 26 families in Chinese cabbage fields, 54 weed species 22 families in potato fields, 62 weed species 25 families in sweet potato fields, 87 weed species 29 families in red pepper fields, 79 weed species 28 families in corn fields, 84 weed species 29 families in soybean fields. The most dominant weed species in upland crop fields of Gyeongnam province were Alopecurus aequalis var. amurensis 20.7% (barley fields), Cardamine flexuosa 12.3% (garlic fields), Chenopodium ficifolium 18.7% (onion fields), Portulaca oleracea 8.1% (Chinese cabbage fields), Chenopodium ficifolium 13% (potato fields), Digitaria ciliaris 12.6% (sweet potato fields and red pepper fields) and Digitaria ciliaris 11.3% (corn fields), 13.2% (soybean fields). This information could be useful for establishment of future weed control methods in Gyeongnam province.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.58-64
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• 2015

The black cutworm, Agrotis ipsilon (Hufnagel) is a major insect pest of economic crops including turfgrasses on golf courses. The entomopathogenic nematode, Steinernema carpocapsae GSN1 strain (ScG), a Korean isolate, is an effective biological control agent for soil dwelling and greenhouse insect pests in Korea. In addition, ScG is commercially produced in Korea. We conducted laboratory, greenhouse, and field trials to evaluate efficacy of ScG against black cutworms in turfgrasses. A rate of 63 infective juveniles (Ijs) per larva killed >90% of $3^{rd}$ instars feeding in cups of artificial diet within 3 days. In greenhouse trials against cutworms feeding in pots of turfgrass, efficacy of ScG was higher against $4^{th}$ instars than against $2^{nd}$ instars (90.0 vs 81.2% mortality, respectively, at $2,000Ijs\;pot^{-1}$) in perennial ryegrass, and higher against $3^{rd}$ instars in creeping bentgrass, Agrostis palustris than in zoysiagrass, Zoysia japonica (96.7 vs 52.5% mortality at $100,000Ijs\;m^{-2}$) in pot. The corrected mortality of $4^{th}$ instar was 79.9% at the rate of $100,000Ijs\;m^{-2}$ in the creeping bentgrass in the field. So ScG could be used as biological control agent against black cutworm in turfgrass of golf courses.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.268-277
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• 2015

Organic fertilizer preparation was developed with organic materials to improve growth and qualities of cool-season turfgrass species. Organic fertilizer preparation were contained with essential macronutrient elements and organic matter for growth of cool season turfgrass. Four preparations of organic fertilizers were tested on creeping bentgrass (Agrostis palustris Huds) cultivar Penn-A1 and Kentucky bluegrass (Poa pratensis L.) mixed cultivars (Midnight 33%, Moonlight 33%, and Prosperity 33%) by one time application on fifty days after sowing. Two species of cool season turfgrasses were evaluated on turfgrass coverage, growth on NDVI (Normalized Difference Vegetation Index) and qualities from fall season to spring season in sod producing farm. It were found significantly difference found on turfgrass coverage, turf color, chlorophyll contents and growth increase on two species of cool season turfgrasses. Turfgrass coverage, chlorophyll content, turf color and growth increase of organic fertilizer preparation were significantly increased on creeping bentgrass cultivar and Kentucky bluegrass mixed cultivar for six time investigation in spring season. These results may indicate that the use of some preparation is beneficial for sod producing sod and turfgrass management.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.249-255
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• 2015

Trichoderma spp. were famous fungi used for turfgrass management in golf course. This study was conducted to evaluate effects of two microbial fertilizers containing Trichoderma harzianum and T. atroviride on the growth and quality of creeping bentgrass with turf color index, chlorophyll index, root length, shoot number, clipping yield and nutrient content. Treatments were designed as follow; non-fertilizer (NF), control fertilizer (CF), T. harzianum (TH), and T. atroviride (TA). Chlorophyll index and root length of TH and TA were increased than these of CF and shoot number and content and uptake of nitrogen (N) of TA higher than these of CF. The N content in turfgrass tissue was significantly related to shoot number, root length and N uptake (P<0.05) and shoot number was positively relate to chlorophyll index (P<0.05). These results indicated that application of Trichoderma harzianum and T. atroviride improved a growth and quality of creeping bentgrass by promoting N uptake.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.1-9
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• 2015

Many irrigated and drainage canals, reservoirs, lakes, and rivers are choked by the explosive growth of aquatic weeds, resulting in enormous direct loss in Korea. Distribution of aquatic weeds and exotic invasive plant species in irrigation and drainage waterways, and riparian wetlands was reviewed to provide basic information for management of aquatic weeds and invasive plant species in wetlands. Dominant emergent weeds in canals, reservoirs and lakes were Phragmites communis, Leersia japonica, Zizania latifolia, Conyza canadensis, C. annuus, Rumex crispus, Panicum dichotomiflorum, Bidens frondosa, and Oenothera odorata. Dominant emergent weeds in wetlands of rivers include Digitaria sanguinalis, P. communis, R. crispus, Artemisia princeps, Humulus japonicus, Echinochloa crusgalli, B. frondosa, and Persicaria thunbergii. In irrigation and drainage canals and lakes, dominant submersed weeds were Hydrilla verticillata, Najas minor, Potamogeton malaianus, P. crispus, Ceratophyllum demersum, Myriophyllum verticillatum, Salvinia natans, and Trapa natans. Dominant exotic weeds in wetlands include Trifolium repens, O. odorata, C. annuus, B. frondosa, Avena fatua, Ambrosia artemisiifolia, X. strumarium, and P. dichotomiflorum. Approaches to aquatic weed control were mechanical, chemical and biological control techniques. Periodic monitoring of aquatic weeds and exotic weeds, and their integrated management studies are needed in waterways and riparian wetlands in Korea.

• Weed & Turfgrass Science
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• v.6 no.3
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• pp.212-221
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• 2017

An actinomycetes isolate G-0299 obtained from a forest soil showed strong phytotoxic activity to Digitaria ciliaris. For the foliar application study, the culture filtrate of the isolate G-0299 showed strong herbicidal activity only to D. ciliaris among the 12 monocot and 5 dicot weed species. And herbicidal activity at a concentration of 500, 250, 125 and $62.5{\mu}gmL^{-1}$ of culture filtrate was 100%, 98%, 70% and 40%, respectively. Phytotoxic symptoms of the culture filtrate by foliar application were desiccation and burn-down or bleaching of leaves and finally plant death. And then the herbicidal activity was exhibited only under the light condition. Also, chlorophyll loss of D. ciliaris leaf tissues in the light condition was much higher than in the dark condition and then chlorophyll content decreased 82%, 5%, respectively. In conclusion, our results suggest that soil bacteria, isolate G-0299 could be a good candidate for new bio-herbicide and provide a new lead molecule for a more unique herbicide.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.374-379
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• 2014

After completing deacidification process and evacuating rest of solvent, white fine particles of MgO are found on the surface of archival materials, such as books and documents. When MgO particles remain on the surface of archives, instead of being well dispersed and absorbed into cellulose fiber of archives, such white fine particles are found. These particles have raised concerns for employees' deacidification environment and their health; however, the concerns have not been addressed. To find the cause of white fine particles on the surface of archives after deacidification process and to propose the its solution, an acidic paper and wood free paper were applied with deacidifying chemicals. We analyzed the domestic and abroad deacidifying chemicals' physical properties and conducted deacidifcation processes to find effects of different contents and sizes of MgO on white fine particles. When the size of MgO particle was 847 nm, there was significantly less amount of white fine particles on the surface of archival materials. This means that the size of MgO particle plays a significant role in producing white fine particles on the surface of archives.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.224-231
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• 1995

Paraquat, the representative bipyridilium herbicide, has high phytotoxic activity through generating toxic oxygen species such as superoxide, hydrogen peroxide and hydroxy radical. The response patterns of plants to paraquat were various. It was assumed that the different response was derived from different antioxidative mechanisms including antioxidative enzymes and antioxidant. Paraquat treatment increased reducing sugar content and malondialdehyde formation at 35 days after treatment in a dose-dependent manner but chlorophyll content decreased. Glutathione content increased by paraquat treatment and tolerant species showed more glutathione content than susceptible species. Superoxide dismutase activity increased with the increase in paraquat concentration and that was higher in tolerant species than susceptible species. Photosynthetic activity(PSII activity) was affected by paraquat, so the susceptible species showed more reduced oxygen evolving capacity than tolerant species. Catalse, NADPH-cytochrome C reductase, and malate dehydrogenase, the enzymes tested in this study, showed that the activities decreased by paraquat treatment. Further studies are necessary to determine whether antioxidative system cause the tolerance to paraquat.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.390-399
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• 1997

This experiment was conducted to introduce PAT (phosphinothricin acetyltransferase, non-selective herbicide bialaphos resistant gene) gene into potato (Solanum tuberosum. cv. Desiree). Optimal shoot regeneration from leaf discs and stem segments was obtained in MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L BA, and the frequency of shoot regeneration was 54% in left discs and 46% in stem segments. In this condition, leaf discs and stem segments of potato were co-cultivated with A. tumefaciens MP90 which contained binary vector with GUS: :NPTII gene and PAT gene. Transgenic shoots were regenerated from leaf and stem-derived calli on selection medium with 100mg/L kanamycin. The 100${\mu}M$ acetosyringone treatment during the co-cultivation highly enhanced(4 times than the control) the shoot regeneration on selection medium. When the putative transgenic plants were transferred to medium with 10mg/L basta, all of them were survived. After PCR. GUS test, and Southern blot analysis of the survived plant, we confirmed that the gene was stably integrated into the potato genome and expressed. After the transgenic plants were transplanted in soil, and the transgenic plants were sprayed with the herbicide basta (300ml/10a), the transgenic plants remained green but control plants were died.