• Weed & Turfgrass Science
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• v.3 no.2
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• pp.143-149
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• 2014

This study was conducted to evaluate the effects of the mixture ratio of soil amendments blended with coco peat (Coco) and American soldier fly cast (SFC) on the physicochemical properties on the sand green. pH and EC of soil were significantly related to mixture ratio of SFC, Mix1, Mix2 and Mix3. Capillary porosity, air-capillary porosity and total porosity of root zone mixed SFC, Coco, Mix1, Mix2 and Mix3 were met to the USGA green specification. The mixture ratios of Mix1 and Mix2 in root zone were positively related capillary porosity and total porosity, and air-capillary porosity was negatively related capillary porosity and hydraulic conductivity. Capillary porosity of Mix1, Mix2 and Mix3 blended SFC and Coco was affected by SFC and Coco, and total porosity by Coco. These results showed that soil amendments blended SFC and Coco was developed capillary porosity and hydraulic conductivity on the USGA sand green than these of SFC.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.211-218
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• 1984

In order to establish the chemical weed control systems in orchard, field experiments were conducted to evaluate the effects of spray methods and mixing of herbicides. The mixtured dosage of glyphosate 100cc/10a and 2,4-D 75㏄/10a showed higher control effects than mono-treatment of glyphosate and paraquat on Artemisia vulgaris var. indica and Polygonum hydropiper L. And oxyfluorfen was more effective in reducing the cover rate and dry weight of weeds than simazine and alachlor on 75th day after treatment. In the mixing experiment of land and foliar appling herbicides. The effect of glyphosate on May 17 followed by oxyfluorfen on June 12 showed the best control effect.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.283-290
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• 1988

This study was conducted to clarify the identification of phytotoxic compounds from 5 upland weeds which had been collected at their maturity age in the field of Kyungpook province, Korea. 5 weed species including Stellaria aquatica strongly inhibited the lettuce seed germination. These 5 species were Amaranthus lividus, Stellaria aquatica, Achyranthes japonica, Polygonum perfoliata and Galinsoga ciliata. the degree of inhibitory effects according to various solvent extracts such as ethanol, aceton, chloroform and ether was different as species. In total phenol and diphenol content G. ciliata had largest amount of total phenol with 2.75mg/g, P. perfoliata 1.8mg/g, S. aquatica 1.7mg/g, A. lividus 1.28mg/g, A. japonica 1.27mg/g respectively. A. lividus had much amount of p-cresol, hydroquinone, ferulic, caffeic, p-cl-benzoic and p-coumaric in order. S. aquatica, A. japonica, P. perfoliata and G. ciliata had a large quantity of ferulic, caffeic, 7-OH-coumarin and protocatechuic acids in common. The amount of fatty acids was existed 8.49mg/g in S. aquatica, 7.14mg/g in A. japonica, 7.10mg/g in G. ciliata, 5.49mg/g in P. perfoliata and 4.2mg/g in A. lividus respectively. Most of 4 weeds except G. ciliata had much oxalic acid to the extent of 14-22mg/g. however it appeared that G. ciliata had much quantity of feruic and citric acids.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.245-249
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• 1989

The effects of varying concentrations and durations of butachlor [N-(bytoxymety 1,)-2-chlor -2, 6-diethy lacetanilide treatment on oat(Avena sativa L.) root cell division and protein synthesis were studied. The highest concentration ($1{\times}10^{-3}M$) of butachlor caused the significant inhibition of cell division after 18hrs treatment. After 18hrs treatment, 59% and 82% inhibition of cell division occurred at $1{\times}10^{-4}M$ and $1{\times}10^{-3}M$, respectively, while 9% inhibition of cell division did at $1{\times}10^{-6}M$ concentration at the same exposure period. To investigate protein synthesis, the oats were treated for 18 and 24hrs with concentrations ranging from $1{\times}10^{-6}M$ to $1{\times}10^{-3}M$ butachlor. After 18hrs, butachlor treatment of oat with $1{\times}10^{-4}M$ inhibitited 23% protein synthesis, and butachlor treatment with $1{\times}10^{-4}M$ caused 34% inhibition after 24hrs. With SDS-PAGE of proteins extracted from oat root tips, butachlor usually inhibited the 16, 18, 30, 43 and 43.5 kD polypeptide, and proteins of root tips are made up of subunits below 100 kD polypeptide.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.243-251
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• 2010

The study was conducted to evaluate the weed suppressing effects of two winter cover crops, Chinese milk vetch (CMV) and rye, in minor cereal fields in 2009. The suppressing activities of cover crops were due to the allelopathy of cover crops during weed emerging periods and competitive activity during vegetative growth of weeds. Weed suppression by cover crops were changed from 26.5 g $m^{-2}$, 0.1 g $m^{-2}$ and 0.2 g $m^{-2}$ in control, rye field and CMV field, respectively, on June 22 to 428.6 g $m^{-2}$, 1 g $m^{-2}$ and 403.9 g $m^{-2}$ in control, rye field and CMV field, respectively, on July 22. The weed dry weights were further changed to 656.3 g $m^{-2}$, 607.8 g $m^{-2}$ and 511.8 g $m^{-2}$ in control, rye field and CMV field, respectively, on August 22. The suppressing effect of cover crops also observed in minor cereals. Plant height and dry weight of sorghum was reduced to 68.7% and 33.6% of handweeding, respectively, on August 5. The reduction was recovered to 82.7% and 55.6% of control, respectively, on August 26. In addition, heading date of minor cereals was delayed by 7 days with rye.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.315-320
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• 2015

Burcucumber (Sicyos angulatus) is an annual invasive plant species originated from North America. This species grows by twining around tree trunks, and blocks other plants from photosynthesis. Thus, it has caused the destruction of the ecosystem and biological diversity by threatening native plants. This study was performed to find out the effect of different soil water content (20%, 13%, 10%, 3%) and various shading degrees (0%, 60%, 80%) on the growth and photosynthesis-related activity of burcucumber. In the responses of burcucumber to soil water content, plant height (PH), leaf length (LL), leaf width (LW) and photosynthetic efficiency (PE) were lower at 20% water content than 10% reflecting that burcucumber plant grow well in the less dry soil and shows poor growth under wet soil condition. In shading experiment, PH, LL, LW and PE were lower at 80% than 60% shading and in general, the growth characteristics were lowered as the shading intensity increased. The improved growth of burcucumber under highly or moderately shaded condition implies that the plant can grow well without growth retardation and can be adapted to shading condition with other tall plant species including tree. Further study on the combination effects of above factors should be conducted in future for effective ecological control of burcucumber.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.84-89
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• 1987

This study was conducted to determine the combining effects of a synthetic brassinolide such as homobrassinolide (HBR) with auxin types on the curvature of radish petiole. HBR has no direct effect on the petiole curvature of radish, regardless of concentrations used. Among the natural known plant growth regulators, NAA at 100ppm showed the highest ourvature at 12 hours after treatment. The synthetic auxins such as 2,4-D and MCP resulted in about three times greater effect on curvature than the untreated control, and their effects lasted till 36 horns after treatment, showing much better effect on curvature than that of the natural auxin types of plant growth regulators. The mixture of MCP at 3 ppm with HBR at 100ppm increased petiole curvature of radish seedlings as much as three times greater than that of a single application of HBR. However, the mixture of HBR at 100 ppm plus 2, 4-D at 100ppm increased the petiole curvature of radish seedlings about eight times greater than that of the HBR single application, showing existance of strong synergistic reaction and the most effective combination, and suggesting possibility of a prectical implementation in agriculture.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.58-63
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• 1987

Laboratory and greenhouse studies were conducted to evaluate effects of spray volumes and surfactants, L-77 and Triton CS-7 on leaf retention of glyphosate in Zea mays, Hordeum vulgare, Artemisia princeps, Trifolium repens and Equisetum arvense. Leaf retention was increased when glyphosate with L-77 or Triton CS-7 was applied in a spray volumes of 10-20 l/10a in Zea mays and 40 l/10a in Artemisia princeps but decreased when spray volumes were higher than above volumes and 40-80 l/10a in Trifolium repens. Hordeum vulgare leaves retained more spray when glyphosate with L-77 or Triton CS-7 was applied in all spray volumes tested. Equisetum arvense retained higher amount of spray by application of glyphosate with L-77 compared with Triton CS-7 and no surfactant treatments.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.56-62
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• 1985

Effects of butachlor [N-(butoxymethyl)-2-chloro-2', 6'-diethyl acetanilide] and 1,8-naphthalic anhydride (NA) on post-germination growth, mesocotyl and root anatomy and root-cell membrane permeability of rice (Orvza saliva L.) were investigated. Lengths of mesocotyl and radicle were markedly decreased as the application rates of butachlor increased from 0.1 to 100 ppmW and NA from 1 to 100 ppmW, but there was no effect on coleoptile elongation. Application of butachlor-NA resulted in increase in coleoptile elongation, but decrease in mesocotyl elongation. Partial breakdown of cortical cells in root and mesocotyl was caused by either trutachlor or NA treatments, resulting in increase in intercellular air space. Further increase in the intercellular air space of root and mesocotyl was obtained when butachlor was applied in combination with NA. Increase in root-cell membrane permeability occurred when either butachlor or NA was applied. However, butachlor-NA treatments resulted in reduction in the permeability.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.130-138
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• 1987

The effects of light and storage conditions on the germination of Oenothera lamarckiana were investigated. Germination was induced by red light, but inhibited by green, blue or infrared. No germination occurred in the dark. Radicle was more photosensitive than other parts of the seed. The rate of germination was proportional to increase in Light intensity ranging from 10 to 3000 Lux. Photosensitivity occurred 6 hrs after water imbibition of air-dried seeds. Maximum photosensitivity was detected 1-2 days after seeding under the light condition at 300 Lux. Germination was almost completed 3 days after seeding. When seeds stored in the chilling and wetting condition were kept at constant temperature in the dark, they germinated well. Air-dried seeds, however, didn't germinate. Whereas, the seeds which kept at alternating temperature had the tendency that seeds stored at room temperature (25$^{\circ}C$) germinated better than those stored at low temperature (4$^{\circ}C$).