• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.261-267
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• 2012

Coastal sand dunes are important for ecosystems due to the variety of rare species that can be found in this kind of habitat, and the beautiful landscapes they create. For environmental remediation, a potential strategy is phytoremediation using the symbiotic relationship of plants and microbes in the rhizosphere, which has proven ecologically sound, safe, and cost effective. Ninety-five colonies were isolated from the rhizosphere soil (RS) or rhizoplane (RP) of Rorippa islandica, Rumex crispus, Artemisia princeps var. orientalis, Lilium sp Stellaria media, and Gramineae. These colonies were then tested for plant growth promoting activities (PGPAs) such as 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and siderphores synthesis ability. In addition, salt tolerance was evaluated at 4% and 8% salt concentrations. It was observed that amongst the test subjects about 50% of the strains had a high resistance to salinity. Many of them could produce indole-3-acetic acid (IAA) IAA (in RS 13.9% and in RP 7.6%), exhibited ACC deaminase activity (55.8% in RS and 36.6% in RP), and could synthesize siderphores (62.7% in RS and 50% in RP). Correlation coefficient analyses were carried out for the three kinds of plant growth promoting abilities (PGPA) and salt tolerance. A positive correlation was found between an ability to synthesize siderphores and ACC deaminase activity (r=0.605, p<0.037). Similarly, positive correlations were noted between salt tolerance and ACC deaminase activity (r=0.762, p<0.004, r=0.771), and salt tolerance and an ability to synthesize siderphores (r=0.771, p<0.003).

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.72-79
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• 2008

Phytosociological study was carried out to investigate the structural characteristics of Humulus japonicus community in the Middle area of Korea. The vegetation data of total 67 $relev\acute{e}s$ were analyzed by the $Z\ddot{u}rich$-Montpellier school's method. Upper layer plant communities of Humulus japonicus were classified into four community groups : Humulus japonicus-Artemisia princeps community, Chenopodium album community, Setaria viridis-Echinochloa crus-galli community and Typical community. Lower layer plant communities were classified into five community groups : Galium spurium-Stellaria aquatica community, Equisetum arvense community, Persicaria theunbergii community, Echinochloa crus-galli-Digitaria ciliaris community and Typical community. According to the results of canonical correspondence analysis by vegetation and environmental factor, Setaria viridis-Echinochloa crus-galli community of upper layer was distributed throughout the soil with high relative light and soil hardness. Chenopodium album community appeared in the soil with high pH. Galium spurium-Stellaria aquatica community of lower layer was formed in the high soil pH. Persicaria theunbergii community and Echinochloa crus-galli-Digitaria ciliaris community were distributed in the soil with high moisture.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.236-242
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• 1987

The study was conducted to interprete the fluctuation of weed vegetation in plant-sociological impacts as affected by the mixture use of oxyfluorfen and glyphosate with various dosages. Also, intended to know the real interaction between two herbicides in weeding efficacies. The better efficacy from the above mixture was recognized than from the oxyfluorfen + paraquat mixture on the perennial-sites. In lower rate mixture of oxyfluorfen, the dominance index was increased by the annual grass species (ie. Digitaria), and of glyphosate by the biennial Stellaria and perennial species (ie. Artemisia). Also, the positive maximum action of both oxyfluorfen and glyphosate in various mixture rates was categorized upto 0.55kg ai/ha for oxyfluorfen and 0.35kg ai/ha for glyphosate, respectively. However, the interaction between the above two herbicides recognized actually as negative. Consequently, the use of mixture compound of oxyfluorfen with glyphosate are expected rather to promote the control efficacy of specific weed species, to enlarge the weeding spectrum and to prolong the weeding periods than to reduce the application rate of both chemicals depending on any synergic interactions.

• Journal of Environmental Science International
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• v.16 no.6
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• pp.751-761
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• 2007

This study is carried out through ecological situation of native Bupleurum latissimum habitats and the research of environmental conditions for conservation of native sites, restoration of alternative habitats and preliminary data for application of useful medicinal plant. Native Bupleurum latissimum habitats were distributed on lower and middle part of the mountain from Altitude 54m to 185m, and the directions of slope were researched as usually northen and western slope. As a result of phytosociological research in 12 stands of native Bupleurum latissimum habitats, they were seperated to two communities(Bupleurum latissimum typical community and Bupleurum latissimum-Galium spurium community) in accordance with containable rate of the organic matter and soil hardeness. Soil condition is usually constituted as loamy sand and clay loam. Bupleurum latissimum is propagated in valuable soil conditions. Bupleurum latissimum lives with Morus bombycis, Reynoutria sachalinensis in Bupleurum latissimum typical community and Thalictrum aquilegifolium, Stellaria media, Hedera rhombea etc. is appeared with Bupleurum latissimum in Bupleurum latissimum-Galium spurium community. Especially, companion species were researched as Aster glehni, Dystaenia takeshimana and so on. The flora of vascular plants in this study is 44 families, 88genus 82species, 2 subspecies, 14 varietas, 4 forma and total 102 taxa. Plants of compositae occupied 10.78% among whole of them.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.7-12
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• 1977

In order to find out the optimum weeding date for growing barley in paddy field, several kinds of weeding dates and frequencies were made and compared. The results are summarized as follows: 1. As far as the weeding frequencies were fixed with one time, an immediate weeding after wintering resulted better barley grain yield and yield components by causing decreased yield of weed. 2. Maximum allowable date to be free from the weed competition were estimated as not late than February 10 or at most february 25. 3. It is considerable that the effect of weeding was continuously found till March 11 but no significant weeding effect was found when the weeding was done after April. 4. The competition of weed and barley was relatively so higher from February 25 to March 30 that the control during this period seemed to be very effective by causing little decrease in barley grain yield. 5. Major overdominant weeds observed in the paddy field for barley growing period were Alopecurus aequalis S., Stellaria alsine G., and Galium aparin L., in the order of degrees.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.560-566
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• 2016

Imports of genetically modified (GM) soybeans (Glycine max) for food or feed consumption in Korea have been increasing. Although the cultivation of GM soybeans has not yet been allowed in Korea, the number of field tests for GM soybeans has also been rising. This study was conducted to investigate whether herbicide tolerant GM soybean can survive and persist in uncultivated environments when they escape from transportation routes or from isolated fields. Seeds of GM and non-GM soybeans and wild soybeans (Glycine soja) were buried in 2 and 15 cm soil depths and their viability was examined after 1, 2, 6, and 10 months. GM and non-GM soybean seeds completely lost their viability within six months of burial, whereas seeds of wild soybean maintained their viability during the study period. Seeds of soybean and wild soybeans that were sown on the soil surface germinated and grew to vegetative cotyledon stage. Seedlings of GM and non-GM soybean did not compete well with weeds, including Cerastium glomeratum, Alopecurus aequalis var. amurensis, Capsella bursa-pastoris, Conyza canadensis, Stellaria aquatica, and Erigeron annuus. Also, GM soybean did not survive through winter. However, wild soybeans competed well with the weeds and became dominant in August. Herbicide tolerant GM soybean is unlikely to persist under uncultivated environments and to become weeds.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.19-25
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• 2015

The purpose of this study is to reveal the effect of plant life cycle to plant settlement by 1 year monitoring. The subjects of monitoring are the plants (3 plant life cycle, 9 taxa) well established in the mesocosm. 18 mesocosms were divided into 3 sets and water levels were maintained at 0, 20 and 60 cm during 16 weeks from mid-May, respectively and at 0 cm except these 16 weeks. Height and population size of transplanted perennial plants (Scirpus tabernaemontani, Zizania caduciflora, Typha (Typha angustifolia and Typha orientalis)) at 1st year were not affected by diverse water level, though any more seedlings of these species were not settled at this condition. In contrast, water level condition strong influenced annual and biennial plant, relatively. As a result, timing and duration of flooding have great effect on successful settlement of annual and biennial plant without rhizome.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1274-1279
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• 2005

The complex vegetation and plant species distributions within riparian corridors influence plant species diversity patterns at both local and regional scales and further reflect both natural and anthropogenic disturbances. Because of these characteristics, riparian zones are often the ecosystem level component that are most sensitive to changes of the surrounding environment; they provide early indications of environmental change and can be viewed as the important source in the watershed. The objectives of this study were two concepts: first, document the composition and dominance of plant communities of riparian areas in the stream, second, compare species composition and temporal diversity between stations in riparian areas of the Ian Stream. The flora was composed to total 158 kinds of the vascular plants as 49 family, 54 genera, 145 species, 12 varieties, 1 forma When the naturalized plant were applied to the recent classification system 280 kinds, the naturalization rate was $10.8\% higher than that of mean value($10.3\%$) of the Korean mountain district. Furthermore, urbanization index (UI) was $6.1\%$. The dominant vegetation communities were distributed in the habitats of three compartments from upstream to downstream. The vegetations were included Phragmites japonica, Salix gracilistyla, S. hulteni and Robinia pseudo-acacia in the riparian area, and Persicaria sieboldii, Stellaria alsine var. undulata, Draba nemorosa var. hebecarpa, Capsella bursa-pastoris, Lepidium apetalum, Bidens frondosa, Trigonotis peduncularis and Hemistepta lyrata in the sandbank or the riparian area, and Equisetum arvense, Humulus japonicus, Persicaria perfoliata, Trifolium repens, Artemisia princeps var. orientalis, Lactuca indica var. laciniata, Avena fatua, Agropyron yesoense, Oenothera odorata, Viola mandshurica, Rumex crispus in banksides, respectively.

• The Korean Journal of Ecology
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• v.18 no.4
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• pp.471-481
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• 1995

The weed population dynamics as affected by contrasting conventional tillege (CT) and no-tillage (NT) practices with a minimum herbicide application was studied in Athens, Georgia, U.S.A. Common chickweed (Stellaria media) was the most common spring weed while johnsongrass (Sorghum halepense), sicklepod (Cassia obtusifolia), and pigweed (Amaranthus retroflexus) accounted for 89∼97％ of net production during summers of 1983 and 1984. Total weed production in summer of 1984 was 2∼5 times greater than that of 1983. Weed production was greater in NT plots than in CT plots in summer of 1983, but reverse was the case in summer of 1984. In spring, net production in NT plots was greater than that in CT plots, especially, in 1985. Species diversity was consistently higher in NT plots, but in the wet summer of 1984 the pattern was different, with higher diversity in CT plots. Weed species diversity was higher in the spring rye crop than in the summer grain sorghum crop. The larger but less diverse weed populations in summer of 1984 indicated that these populations experienced competitive exclusion. Under the favorable summer moisture conditions the three dominant species grew so vigorously and quickly as to exclude many less common species that were able to survive under the drier conditions in 1983. The three dominant species not only excluded other weeds in 1984 but also greatly reduced crop production. The perennial johnsongrass was equally successful, or even more so, in CT plots as in NT plots. Plowing did not kill johnsongrass rhizomes but tended to break them up, thus increasing the number of individual plants that appear after the plowing. It means that johnsongrass was not controlled by the plowing. In summer of 1983, a moderate amount of weedy growth was maintained with a minimum amount of gerbicide application in NT and CT plots. It is possible that a small mixed weed population would be beneficial by providing cover for predatory and parasitic arthropods, and by reducing soil temperature and moisture losses.

• Journal of Environmental Science International
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• v.21 no.11
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• pp.1419-1424
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• 2012

Purpose of this study was to evaluate germination characteristics of soil seed bank in rural stream topsoil using seedling emergence method in order to provide data for future ecological restoration of stream utilizing topsoil. There were 24 families, 52 genera, 61 taxa of soil seed bank flora found in topsoil from 6 rural streams. The most frequently found taxa were Compositae (12 taxa) followed by Gramineae (8 taxa), Caryophyllaceae (5 taxa), Cruciferae (4 taxa), Scrophulariaceae, Labiatae, Polygonaceae and Cyperaceae. Plant with the most number of germination was Stellaria aquatica followed by Erigeron annuus, Imperata cylindrica var. koenigii, Poa annua, Cyperus microiria and Veronica undulata. Naturalized plants found were Erigeron annuus, Rumex crispus, Oenothera odorata, Cerastium glomeratum, Bidens frondosa, Erigeron philadelphicus, etc.