• Korean Journal of Weed Science
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• v.11 no.3
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• pp.224-228
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• 1991

This study was carried to know factors affecting emergence of major upland weeds in soil in order to get basic information on weed control methods. Firthy eight percent of weed seeds were distributed within soil surface to 10cm in soil and 2% of weed seeds were observed in 40~50cm soil layer in field. As planting depth was deeper, emergence of weeds became poor. However Capsella bursa-pastoris can emerge at soil surface. Amaranthus retroflexus, Amaranthus lividus, Porturaca oleracea, Chenopodium album, Solanum nigrum upto 3cm, Eleusine indica, Echinochloa crus-galli, Setaria viridis, Digitaria sanguinalis upto 7cm. Emergence of weeds was very poor in very acid soil but good in soil pH 5.5~6.0. However emergence of weed was not affected by pH 3.5~4.0 or above. Emergence of E. indica, C. bursa-pastoris, A. retroflexus, A. lividus, C. album, E. crus-galli, Solanum nigrum, and S. viridis was good in loam soil and P. oleranea, D. sanguinalis in sandy loam soil. Emergence of weed seeds was not affected by fertilization.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.317-323
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• 1988

This survey was conducted to know characterization of weed occurrence under protected culture conditions at Yousong in 1985. Chenopodium album, Polygonum hydropiper, Portulaca oleracea and Digitaria sanguinalis were dominated in outdoor, whereas Capsella bursa-pastoris, C. album, D. sanguinalis and P. oleracea were dominant in polyethylene house. More weeds emerged in mulching plots and dry weight of weeds was greater in non-mulching plots. Summer broadleaf weeds and summer grasses were abundant in outdoor, whereas non-mulching plots in polyethylene house was dominated by winter broadleaf weeds, and mulching plots in polyethylene house were dominated by winter grasses and winter broadleaf weeds in early stage and summer grasses and summer broadleaf weeds in late stage. Simpson index was high in polyethylene house and Shannon's diversity index, maximum diversity for the Shannon diversity index were lower than eveness using the Shannon diversity index and this trend was more remarkable in mulching and mulching in tunnel than in non-mulching under polyethylene house condition. Shannon diversity index, maximum diversity for the Shannon diversity index were high in mulching or tunnel, and Simpson index was high in non-mulching in outdoor condition. Interspecific competition was more severe than intraspecific competition in both conditions.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.53-56
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• 1982

In order to establish the chemical weed control systems in orchard, efficacy of glyphosate and paraquat with oxyfluorfen, simazine and alachlor were evaluated in pear and peach orchards. Dominant weed species existed before glyphosate or paraquat application were Artemesia princeps, Calystegia japonica, Erigeron canadensis, and Lepidium apetalum, but Digitaria sanguinalis was one of the most dominant weeds throughout growing season of fruit trees. Gtyphosate at 120g/10a followed by oxyfluorfen at 04g/10a drastically reduced number of weeds and fresh weight of weeds and was found to be the most effective method for controlling weeds in orchard. Paraquat at 100g/10a followed by oxyfluorfen at 117g/10a and sequential application of glyphosate at 120g/10a also provided good weed control.

• Korean Journal of Weed Science
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• v.17 no.2
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• pp.157-162
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• 1997

This study was conducted to investigate the change of weed community on paddy-upland rotation in 1996. In paddy-upland rotation, dominant weed species in paddy condition were Cyperous amuricus, Echinochloa crus-galli, Rotara indica and Lindernia procumbens. They were E. crusgalli, Digitaria sanguinalis and C. amuricus in upland condition. The number of weed occurrence on paddy and upland rotation reduced about 74-78% as compared with continuous paddy and upland condition. Similarity coefficient and Simpson index on paddy and upland rotation was 8-64, 0.34-0.35, respectively.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.67-71
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• 1997

This experiment was conducted to test the allelopatic activity on germination and early seedling growth of weed species by barley and sorghum plants residues. The fresh barley extraction inhibited the germination and early seedling growth of weeds, Echinochloa crus-galli, Sataria viridis, and P. oleracea. As the extract concentration increased, the germination and early seedling growth of weeds was significantly inhibited. The water extraction of dried barley and sorghum residues also ehibited the strong inhibition effect on germination and Barley seedling growth of weeds. Digitaria sanguinalis, Siegesbechia pubescens, Sectaria viridis, P. oleracea, E. crus-galli. In the dried barley and sorghum residues mixture into the vermiculite, as the dried residue concentration ncreased, emergence percentage, length of shoot and root of weeds, D. saguinalis, S. viridis, S. pubescens, Ammaranthus lividus, and Solanum nigrum, was significantly inhibited. More than 10% concentration of dired residue caused 80% emergence percentage and growth inhibition. From this study, we conclude that barley and sorghym weeds. These results suggest that barley and sorghum has some possibility to control some weed species like natural herbicide.

• The Plant Pathology Journal
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• v.24 no.4
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• pp.453-460
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• 2008

In the course of in vitro and in vivo screening for bioherbicidal agents, a hyphomycete fungus, Myrothecium sp. F0252 was selected as a candidate for the biocontrol of weeds. The isolate was identified as Myrothecium roridum Tode ex. Fries based on the morphological characteristics and 18S ribosomal DNA sequence analysis and registered as Myrothecium roridum F0252. In order to evaluate the in vitro effect of M. roridum F0252 on germination of ladino clover and white clover (Trifolium repens L.) seeds, spore solution of the fungus was employed in two concentrations, $6.5{\times}10^6$ and $2.5{\times}10^7$ spores per mL and then inoculated to the seeds. The fungal spores inhibited the seed germination, infected the seedlings, and caused an abnormal withering and inhibition of seedling growth. In addition, when the herbicidal activity of crude ethyl acetate extract from the liquid culture was assessed on a mini-plant, duck-weed (Lemna paucicostata (L.) Hegelm.), the extract showed high inhibitory effect at the level of $12.5{\mu}g$ per mL. On the other hand, in vivo herbicidal activity of M. roridum F0252 was evaluated by a whole plant spray method. M. roridum F0252 exhibited strong and broad-spectrum herbicidal activity. The herbicidal values ranged from 95-100% against 7 weeds, including Abutilon avicennae and Xanthium strumarium, and 70-80% against Digitaria sanguinalis and Sagittaria pygmaea. When the nutritional utilization (95 carbon sources) pattern of M. roridum F0252 was investigated, it varied with water activity ($a_w$) and temperature conditions, supplying good, basic information in regard to nutritional utilization for proper cultivation and formulation. Our results showed that M. roridum F0252 might be used as a potential biocontrol agent against weedy plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.2
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• pp.62-73
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• 2001

The riparian environments of urban streams in Korea have been disturbed through the channelization for flood control and artificial land use as well as water pollution and flow decrease due to industrialization and urbanization. The flora and vegetation structure were investigated and an implication of stream restoration was discussed for the conservation of biodiversity in the riparian area of the Seunggi stream in Incheon. Naturalized plants and ruderal plants were widely distributed in the riparian area which was disturbed from cultivating, trampling, dumping etc. Submerged and floating hydrophytes were not found in the stream due to channelization and water pollution. Some halophytes were remained in downstream and reservoir after reclamation and embankment. The communities of Humulus japonicus, Panicum dichotomiflorum, Digitaria sanguinalis, Artemisia montana, Amaranthus retroflexus, and Aster pilosus were distributed in the disturbed area of bank slope and floodplain in the stream. As a natural potential vegetation, Phragmites australis in the wet meadow, Typha latifolia, Typha angustifolia, Oenanthe javanica, Persicaria thunbergii, and Penthorum chinense in the marsh, and Salix babylonica and Salix matsudana for. tortuosa in the woodland appeared in the floodplain. The topography in the stream played an important role on the distribution of riparian vegetation in the Seunggi stream. Appropriate methods for conservation and restoration of the riparian ecosystems must be planned on the basis of the actual vegetation in the disturbed urban stream.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.169-175
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• 2007

This experiment was carried out to compare weed occurrence and to evaluate the field performance of some leguminous plant species under no-weeding fallow condition during summer months from middle of June to middle of August. In 2005 and 2006, the first dominant weed species was Digitaria sanguinalis, and other major weed species, such as Cyperus amuricus, Portulaca oleracea, and Amaranthus retroflexus, were similar among treatments. In both years, total shoot dry weight of weeds was the highest In the control plot, and the lowest in the cowpea plot, indicating that cowpea most effectively suppressed the growth of weeds among treatments. When the growth of four different leguminous species were compared after seeding during middle of June in 2006, cowpea and rice bean grew vigorously under no-weeding condition during hot and humid summer months, while wild soybean and hairy vetch did not. Shoot dry weight was in the order of cowpea > rice bean > wild soybean > hairy vetch. In conclusion, cowpea is a leguminous species which can be used as a green manure cover crop during summer months under no-weeding and our climate condition. Further works are needed to use cowpea as a green cover crop during summer months for various cropping systems.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.153-156
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• 2006

As an ongoing research program for the development of environmentally friendly new herbicide, several hydantoin derivatives 5a - 5i possessing amide subgroup were synthesized and shown to have interesting herbicidal activities exhibiting symptoms as Protoporphyrinogen IX oxidase inhibitor under postemergence upland greenhouse screening. Among derivatives tested, compound 5h showed superior herbicidal activity against upland problem weed, digitaria sanguinalis and aeschynomene indica to reference compound fluthiacet-methyl.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.59-64
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• 1990

Wild plants which have potential availability as pasture plants were collected from around Kyungpook province. Plants collected were cultivated in the university farm and their characteristics were investigated and recorded. Seeds of pasture plant resources collected were selected, weighed for 1,000 grains, packaged and stored at $4^{\circ}C$. Species of collected were as follows. Gramineous plants are Cymbopogon totilis var, goeringii Hand Mazz, Pennisetum akioecyriudes L., Dactylis glomerata L., Agropyron tsukushience var transiens Ohwi, Arundinella hirta Tanaka, Themeda triandra var., japonica Makino, Miscanthus sinensis Anderss, Setaria virides L., Digitaria sanguinalis L., Imperata cylindrica var. Koenigii Retz, Cynodon dactylon Pers, Echinochloa crus-galli var. frumentacea Wight, and Avena fatua L., and leguminous plants are Vicia angustrifolia var. segetilis Koch, Kummerowia stipulacea Makino, Kummerowia striata Schindl, Trifolium repens L., Melilotus officinalish L., and Astragalus sinicus L..