• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.3
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• pp.1-8
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• 1980

Eight different weed community types growing in association with transplanted rice were identified in the experimental fields used in these studies. The Importance Value (LV.) of weed species growing in association with rice changed with time. The I. V. of Echinochloa glabrescens Munro ex Hook f. increased from 40 days after transplanting (DAT) until heading and then, decreased from heading to maturity of rice. However, the LV. of Monochoria vaginalis (Burm.) Pres!. and Echinochloa crus-galli ssp. hispidula (Retz.) Honda increased from 40 DAT to maturity while Scirpus maritimus L. decreased from 40 DAT. There was a high negative correlation between grain yield and weed weight at rice heading in all weed communities. The competitive ability of rice against weeds varied depending upon weed species. The highest yield decrease due to weed competition was obtained from the E. crus-galli ssp. hispidula-S. Maritimus community. Forty-two percent yield reduction was caused by competition of 100g dry weight of weeds per square meter of this community type at rice heading. The yield decrease for the same amount of weeds was 10% for the E. glabrescens community, 15% for the M vaginalis community and the M vaginalis-Scirpus supinus L. community and 21% for the M vaginalis-E. glabrescens-Fimbristylis littoralis Gaud.-S. maritimus community type.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.67-74
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• 1990

Weed species investigated along the Nakdong River on September, 1989 were 105 species in 29 families. Vegetation analysis along the Nakdong River using a two dimensional ordination diagram showed the existence of six plant community types, namely, Humulus japonicum, Persicaria thunbergii, Artemisia capillaris, Persicaria blumei-Setaria viridis-Digitaria sanguinalis and Phragmites communis. Especially the largest community type, Phragmites communis had dominant weed species such as Humulus japonocum, Arundinella hirta, Persicaria thunbergii, Setaria viridis, Sasola collina and Persicaria perfoliata.

• Korean Journal of Weed Science
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• v.2 no.2
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• pp.129-140
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• 1982

Herbicides were classified by two-dimensional ordination analysis based on the weed flora which was not controlled by application of a particular herbicide. The number of herbicide group was varied depending upon the weed community type and the experiment site. The technique of the two-dimensional ordination analysis gave more comprehensive informations about selecting of herbicides for increasing the herbicidal efficacy, for increasing the weed spectrum and for reducing the herbicide cost by mixing of herbicides. The two-dimensional ordination analysis could be used not only herbicide classification and selecting effective herbicide or herbicide combination but also can be used for the evaluation of systematic application of herbicides.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.223-245
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• 1983

Nationwide weed survey of paddy rice field conducted in 1981 and 1971 was compared and determined major dominant weed community types distributed by province. Based on the similarity coefficients between 1971 and 1981 the floristic composition based on the degree of dominance was greatly dissimilar while kind of weed flora were not much differed. Degree of dominance were concentrated to perennial weeds in 1981 while these were at animal weeds in 1971. The moat important 10 weed species and their dominance in 1981 were Monochoria vaginalis Presl.(22.2%), Sagittaria pygmaea Miquel(17.5%), S. trifolia L.(9.0%), Poramogeton distinctus Benn.(9.0%), Cyperus serotinus Rottb.(8.5%), Rotala indica Koehne(6.0%), Aneilema japonica Kunth(4.4%), Lindernia procumbens Philcox(3.9%), Eleocharis kuroguwai Ohwi(3.4%) and Ludwigia proarrara Roxb(3.0%), respectively while these for 1971 were R. indica(34.5%), Eleocharia acicularis Roem, et Schult (11.9%), M. vaginalis(11.1%), Cyperua difformis L.(8.7%), Echinochloa crus-galli Beauv.(6.9%), L. procumbens(3.3%), P. distinctus(3.1%), A. Japonica (2.4%), E. kuroguwai(1.8%) and P. hydropiper(1.8%), respectively. Weed occurrence was also closely related with soil type, cropping pattern and cultural practices. Particularly, the occurrence of P. distincrus was negatively correlated with the degree of land utilization. Weed community types dafined by two-dimensional ordination analysis were 11 for Jeonnam province, 9 for Gyeoaggi, Gangweon, Chungbuk and Gyeongnam provinces, 8 for Jeonbuk and Gyeongbuk provinces, 7 for Chungnam province and 4 for Jeju province, respectively.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.36-43
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• 1993

Differences in community space of weed and rice were investigated among five types of rice (Oryza sativa L.) cultivation. The five types employed were three transplanting cultivations such as conventional hand transplanting, machine transplanting with 30-day-old seedling, and machine transplanting with 10-day-old seedling and two direct-seedlings such as flood direct-seeded rice by pregerminated seed and dry direct-seeded rice by dry seed. The greatest competition between rice and weeds as determined by growth rate of rice was found in between 10 and 11 weeks after transplanting (WAT) and/or seeding, irrespective of cultivation types. Competition injury due to weeds was greater in transplanting with 10-day-old seedling than with 30-day-old seedling. The greatest injury in growth of rice was found in direct-seeded cultivation. In transplanting cultivations space occupation by rice in lower than 80 cm height level was low as compared with that by weeds. Plant heights of dominant weeds such as E. crus-galli and E. kuroguwai were shorter by heading date, but taller after the heading date than those of rice. In direct-seeding community space was mainly occupied by the weeds. The pattern of community structure and competition injury caused by weeds showed a similar tendency obtained on the basis of species distribution, number, and dry weight of the occurred weeds.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.20-30
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• 1982

A field experiment was conducted in 1981 at the Crop Experiment Station, Suweon, Korea, in machine transplanted paddy rice field, to study the effectiveness of single herbicide, mixture, and systematic application of herbicides on diversity of weed control spectrum. The rice variety planted was Taebaegbyeo, Indica ${\times}$ Japonica cross bred. Experimental field was dominated by Echinochtoa crusgalli, Eleocharis kuroguwai, and Scirpus hotarui, and importance values based on dry weight of these weeds were 89%, 5%, and 3%, respectively. The mixture or systematic treatments of herbicide were generally more effective than single herbicide applications on weed control. Coefficients of similarity based on floristic composition after herbicide application between Perfluidone (5G) and Chloromethoxynil (7G), and between Pertluidone (5G) and Bifenox (7G), and between Perfluidone (5G) and three types of Butachlor (6G) were low, and these sets seemed to be a good mixture herbicide in paddy fields. While, Perfluidone (5G) had low coefficient of similarity with other single herbicides tested. The information on coefficient of similarity could be used as parameter for selecting herbicides to increase the efficiency of herbicidal performance. Simpson's indices from Butachlor (3.5G)/SL-49 (7G), Butachlor (3.5G)/Pyrazolate (6G), and Perfluidone (5G) treatments were high, and these herbicide treatments tended to the weed community type simplified, while the indices from Perfluidone (5G) + Chloromethoxynil (7G), Butachlor (6G) fb Perftuidone (5G), and Butachlor (4G)/Naproanilide (6G) treatments were low, and these herbicide treatments caused to the community type diversified in terms of floristic composition.

• Journal of People, Plants, and Environment
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• v.23 no.6
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• pp.615-624
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• 2020

Background and objective: Urbanization caused a reduction in urban green space and a lack of community spaces. An attempt to solve these problems, urban gardens, have become popular and are currently being implemented in various downtown areas. However, urban gardens have some inadequate aspects from a visual or landscape perspective. The goal of this study was to examine the possibility of an aesthetic and productive garden space by introducing cultivation methods through the planting system design process. Methods: The design process using plants was classified and presented to suggest the importance of the landscape and aesthetic value. An urban garden space was designed according to the perspective of 'production scenery' and 'participation aesthetics'. According to the characteristics of the plant, urban gardens were divided into vertical type (corn, millet, sorghum), climbing type (kidney bean, cucumber, bitter gourd), and runner type (melon, watermelon, peanut). After classifying plants according to the shape of the root, the structure supporting climbing was installed and the crops were cultivated in an upright form with a tunnel. Results: In the designed cultivation, each crop cooperates, without invading each other's space. Compared with the conventional cultivation, there was little difference in production, and management was made more convenient since weed outbreaks were effectively suppressed while runner type crops cover over the land's surface. Since the positions of each crop are clearly distinguished, the aesthetic value is improved by offering a sense of rhythm with a balanced design. Conclusion: The results suggest that the cultivation methods through the plant system design process have aesthetic as well as productive value, and the design using plants, an infinite living resource, could lead to an expansion of the design field. Moreover, it would enable a sustainable symbiosis between industry and environment. There is potential for the design industry to make significant progress through collaboration with agriculture, horticulture, and landscape architecture.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.208-219
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• 1987

Newly developed several herbicides were evaluated as paddy rice herbicide at the Yeongnam Crop Experiment in 1986. And also, the general situation of rice cultivation between Korea and Japan was compared. Twenty-nine herbicides of the total 59 herbicides were used as paddy rice field in Korea while these were 100 and 187, respectively, in Japan. Among paddy rice herbicides, butachlor was the most important herbicide in both countries. However, the degree of concentration to a particular herbicide was greater in Korea compared to Japan; consumption rate of single butachlor to the total herbicide were 66.5% for Korea and 11.9%r for Japan, respectively. Pyrazolate, pyrazoxyfen and quinclorac were the most promising hebicides in pressed-type rice nurserybed in terms of herbicidal efficacy and phytotoxic effect. For transplanted paddy rice field, single application of NC-311 or combining applications of NC-311 with butachlor or quinclorac gave excellent results at the weed community that was dominated by Echinochloa crus-galli, Aneilema japonica, Ludwigia prostrata, Scirpus hotarui, Cyperus serotinus, Potamogeton distinctus and Eleocharis kuroguwai. Particularly the above combining applications maintained their excellent herbicidal effect up to 3 leaf stage of E. crus-galli without arising herbicidal phytotoxicity. Pyrazolate and three sulfonyl urea herbicides (DPX-5384, NC-311 and CGA 142464) exhibited very high safety against rice. However, Japonica type rice cultivar was a little bit more sensitive than Indica/Japonica type rice cultivar. On the other hand, the effect of these herbicides against E. crus-galli was very strong. Herbicidal effect against E. crus-galli was enhanced through shoot absorption for sulfonyl urea herbicides and root abosorption for pyrazolate and quinclorac, respectively.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.69-74
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• 1983

The behaviour of mixtures of herbicides was determined to obtain the basic informations about effective herbicide use, enhancing herbicidal efficacy and reducing the chemical cost. Fourteen herbicides with 91 mixed combinations were evaluated by Limpel et al method at the Echinochloa crus galli Beauv-Monochuria vaginalis Presl.-Scirpus hotarui Ohwi (importance values of these weeds were 63%, 16% and 10%, respectively) community type. Thirty eight mixed combinations showed the antagonistic response. Among these 14 mixed combinations including chlormethoxynil + naproanilide mixture were greater than 11% in antagonistic effect. On the other hand, 40 mixed combinations including chlormethoxynil + SW751 mixture showed additive response (${\pm}2%$). For synergistic response, 13 mixed combinations were belonged to this group. Particularly, 3 mixed combinations, chlormethoxynil + butachlor, chlormethoxynil + bifenox and nitrofen + ACN/MCPB/nitrofen mixtures were greater than 11% in synergistic effects. The mixture of thiobencarb + oxyfluorfen was analyzed by isobole technique. This mixture showed the synergistic response and the interaction index was approximately 2. The most optimum mixtur for inducing 90%n weed suppression was 0.012 kg ai/ha for oxyfluorfen and 0.45 kg ai/ha for thiobencarb.