• 한국잡초학회지
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• 제18권4호
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• pp.356-363
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• 1998

GIS를 이용한 1981 및 1992년도 우리 나라 전국 논잡초 발생량의 차이를 단위면적당 발생 본수 및 건물중을 가지고 분석한 지도자료를 통하여 보면 각각 다음과 같다. 1. 1981년과 1992년의 발생본수로 본 잡초발생 경향은 충청서부지역은 양년 모두 잡초발생이 많아 비슷한 양상을 보였다. 그러나 1981년에 비교적 많은 발생량을 보였던 강원일부지역은 1992년에는 발생본수가 크게 줄어든 것으로 나타났으며, 1981년에 발생량이 적었던 전남남부지역의 발생량이 많은 것이 특징적인 것으로 나타났다. 2. 1981년도의 우리 나라 논잡초 발생 량을 건물중으로 분석하여 볼 때 1992년도에 비하여 비교적 적은 것으로 나타났으며 주요 발생지역은 중서부지역인 것으로 나타났으며, 1981년도에 상대적으로 논잡초 발생량이 많았던 지역은 충남 당진, 서산, 태안, 청양, 대천, 보령, 공주 등이었다. 또한 건물중으로 볼 때 1992년도 우리 나라 논잡초 주요 발생지역은 중부지역인 것으로 나타났다. 특히 1992년도 논잡초 발생량이 상대적으로 많았던 지역은 경기도 화성, 안성, 용인, 시흥, 강원도 원주, 충북의 중원, 제천, 청원, 보은, 옥천, 영동, 충남의 대전, 예산, 대천, 서산, 당진, 태안, 청양, 보령, 서천, 천안, 아산, 연기, 공주, 부여, 논산, 금산지역이었다.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.317-323
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• 2010

Nutrient availability is a critical component of agroecosystems, and is relevant to both above- and below- ground interactions. The principal objective of this study was to determine how the cessation of fertilization affects the communities of weeds and soil organisms in a corn/wheat field. Changes in dominant weed species, substrate-induced respiration, and the population density of nematodes and microarthropods were evaluated. Microbial substrate-induced respiration (SIR) and the population density of microarthropods decreased following the cessation of fertilization and were partly correlated with the aboveground weed biomass. The cessation of organic fertilizer application but continuing application of inorganic fertilizer reduced the population density of nematodes. In response to the cessation of fertilization, weed communities were dominated by species with little dependency on fertilization. Amaranthus retroflexus was identified as the most dominant species in the corn field; however, it was replaced by Digitaria ciliaris after the cessation of fertilization. In the wheat field, the cessation of fertilization led to a rapid reduction in the biomass of most weeds, except for Vicia angustifolia, supposedly as the result of symbiotic nitrogen fixation. Additionally, the fact that weed biomass was partially correlated with SIR or the population density of microarthropods may reflect a mutual feedback between soil organisms and weeds. The results indicate that the cessation of fertilization alters communities of weeds and soil organisms through changes in weed biomass and interactions with symbiotic microorganisms.

• 한국잡초학회지
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• 제30권2호
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• pp.164-170
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• 2010

유기농 콩 재배에 가장 문제가 되는 잡초를 억제하기 위하여 호밀을 피복작물로 이용하여 콩을 재배하였다. 호밀의 이용방법에 따른 잡초 억제 효과를 보기 위하여 리빙멀치(living mulch), 토양 환원, 호밀 예취구를 두었고, 콩의 재식밀도와 호밀 파종밀도를 다르게 처리하여 잡초의 발생 양상을 비교하였다. 호밀을 리빙멀치로 이용한 처리구가 잡초의 발생과 생 육을 가장 효과적으로 억제하였다. 콩 파종 한달 후의 잡초 억제율은 리빙멀치구가 92.5%에 달하였으며 15일 예취구가 75.4%, 토양 환원구가 67.1%, 30일 예취구가 61.3%에 달하였다. 호밀의 파종 밀도에 따른 효과는 처리구간 차이가 미미하였으나 콩 생육 후기에는 호밀 2줄 파종이 호밀 1줄 파종보다 다소 우수하였다. 콩 재식거리에 따른 효과도 호밀 파종 밀도의 결과와 비슷하여 밀식과 소식간 차이가 인정되지 않았다.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.313-322
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• 2012

A 2-year study (2010-2011) was carried out in order to evaluate the effects of bean and maize intercropping. The experiment tested five different cropping systems: sole cropping of each crop, as well as intercropping of maize/bean with the ratios of 1:3 ($M_1B_3$), 2:2 ($M_2B_2$) and 3:1 ($M_3B_1$), each of which took place in the presence of two weed management systems (no weed control and weed eradication through manual removal), in a factorial experiment based on randomized complete block design using three replicates. Tests of homogeneity of variance for combined data over two years showed that data of both years could be analyzed together. The results showed that the effect of intercropping treatments on all measured traits in maize and bean were significantly different. A minimum land equivalent ratio (LER) for maize (0.78) was obtained for $M_3B_1$ under conditions of no weed control, while the highest LER (1.03) was observed in $M_3B_1$ under weed-free conditions. The highest (0.99) and lowest (0.70) LER values for beans were recorded for $M_1B_3$ under weed-free conditions and $M_3B_1$ under conditions of no weed control, respectively. $M_1B_3$ under weed-free conditions showed the highest total LER (2.02), while $M_3B_1$ under conditions of no weed control showed the lowest (1.48). Results of this study indicated that intercropping bean and maize can be an effective method to increase total productivity, and that the $M_1B_3$ system was the best cropping system for high productivity.

• 한국잡초학회지
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• 제17권1호
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• pp.124-134
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• 1997

As control of plant diseases, insects and weeds were heavily relied on pesticides, residues of pesticides in environment and food supply were recently focused by environmentalists and consumer groups. The reduction of pesticide use was implemented in Sweden, Denmark, Netherland, England, and United States. Therefore, it is very important to discuss environmentally sound systems of weed management including cultural, mechanical, and integrated weed control. Mechanical methods using tillage, cultivation, mulching, burning, mowing, solarization, and UHF are used as one of most effective environmentally sound weed management systems. Cultural practices favoring the crops are excellent weed management measures. Correct seedbed preparation for the soil and cultural system, and use competitive cultivars contribute to weed management. Increasing crop density by higher seeding rate or by narrowing row width and careful attention to optimum fertility to produce vigorous crop plants increase competitiveness of crops against weeds. Crop rotation breaks life cycles of weeds by alternating the crop it must associate with. Herbicides are efficient and profitable to control weeds, but must be part of a total weed management program with use of minimum rate. The best weed management will be an integrated approach including two or more methods to manage weed problems.

• 한국잡초학회지
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• 제32권3호
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• pp.188-194
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• 2012

본 연구는 벼에 대한 물달개비, 벗풀의 경합에 따른 수량피해 예측과 경제적인 잡초관리를 위한 방제필요밀도를 구명하고자 하였다. 수원, 익산, 나주와 대전지역에서 얻어진 성적을 종합한 예측모델식에 따르면 논에서 물달개비의 경합력은 대전 0.0007445, 수원 0.0005713, 익산 0.000988, 나주에서 0.0008846으로 추정되었다. 벗풀의 경합력은 나주 0.001611에서 익산에서 0.002437의 범위를 보였다. 초종별 평방미터당 요방제 필요밀도는 물달개비는 중기제초제 처리시 22에서 39본으로, 벗풀은 8.8본에서 12.9본으로 추정되었다.

• Weed & Turfgrass Science
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• 제6권3호
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• pp.196-202
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• 2017

흑미를 이용한 무논점파 재배방법에 따른 입모, 수량, 품질특성 등을 구명하고 효과적인 잡초방제체계를 결정하여 재배안정화를 유도함으로써 흑미를 이용한 무논점파 재배의 보급 확대를 위한 기초자료를 제공하고자 수행하여 얻어진 결과는 다음과 같다. 흑미 무논점파 재배에서의 효과적인 잡초방제체계는 제초효과가 높고 약해에도 안전하였던 bromobutide thiobencarb (파종 전 5일) followed by bensulfuron mefenacet thiobencarb (파종 후 12일) 체계처리가 유리할 것으로 판단되었다. 파종시기 및 재식밀도에 따른 흑미의 입모수는 파종시기가 늦어지고 재식밀도가 높아질수록 증가하였으며 출수기는 파종시기가 늦어질수록 지연되었으나 재식밀도별로는 차이가 나타나지 않았다. 흑미의 가장 중요한 품질요소인 안토시안함량은 파종시기가 늦어지고 재식밀도가 낮아질수록 높아지는 경향이었으며 완전 착색 현미수량은 5월 30일과 6월 10일 파종 $3.3m^2$당 80주에서 이앙재배 대비 99% 수준으로 가장 높게 나타났다. 이상의 결과들을 종합해 보면 흑미를 이용하여 무논점파 재배를 할 경우 적정 재식밀도는 $3.3m^2$당 80주였고 중만생종 품종으로 사료맥류 후작인 6월 10일 파종까지는 수량감소가 거의 없어 안전하게 재배가 가능하며 식용맥류 후작인 6월 20일 파종에서는 중만생종 품종은 지양하고 조생종 품종을 선택하여야만 비교적 안전하게 재배가 가능할 것으로 판단되었다.

• 한국작물학회지
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• 제44권3호
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• pp.221-224
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• 1999

A field experiment was carried out to observe the weed control effects of vetch and to evaluate vetch characteristics on clay loam soil in no-till direct-sown rice-vetch cropping systems. The effects of weed control, forage productivity, and N content of vetch plants were investigated. With the progress of plant growth, density of Chinese milk vetch (Astragalus sinicus L.) gradually decreased, but densities of foxtail and other weeds decreased steeply due to the depression by the over-shaded vetch canopy in a no-till direct-sown rice-vetch cropping paddy field. The vetch density in tillage systems was lower than in notillage cropping systems. Lower vetch density occurred with an increase in foxtail density and other weeds. Weed control effect increased by the progress of vetch growth, which indicated that the vetch canopy over-shaded the weeds. Vetch straw was degraded rapidly submergence after with water at the time of wet sowing of rice. Early harvesting of vetch seed resulted in lower seed germination. To acquire enough seedlings without re-sowing, the harvesting of seed should be delayed at least 28 days after the flowering stage in order to ensure the vetch population is sustainable in a no-till direct-sown rice-vetch cropping system. In order to improve the survival of vetch plants, vetch seeds should germinate from the heading .stage to before the full-ripening stage of rice plants. To enhance the percent of over-wintering survival, vetch seeds should germinate no later than the end of October in southern Korea. The dry weight of vetch plants increased with the progress of vetch growth until the flowering stage but N content decreased for 30 days from before the flowering stage (2.9%) until the ripening stage (1.8%). We concluded that Chinese milk vetch could have an effect on weed control before the flowering stage, sustainability without re-sowing of seed annually, and effective green manure for rice pre-crop in no-till direct-sown rice-vetch relay cropping systems.

• Journal of Biosystems Engineering
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• 제27권2호
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• pp.143-150
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• 2002

Several researches for site-specific weed control have tried to increase accuracy of weed detection with machine vision technique. However, there is a problem which needs substantial time to perform site-specific spraying. Therefore, new technology for real-time precision spraying system is needed. This research was executed to develope the new technology to estimate weed density and size in real time, and to conduct a real-time site-specific spraying. It would effectively reduce herbicide amounts applied for a crop field. The real-time precision spraying system consisted of a Differential Global Positioning System (DGPS) with an error of 2 cm, a machine vision system, a geomagnetic sensor for correction of view point of CCD camera and an automatic sprayer with separately controlled nozzle. The weed density was calculated with comparison between position information and a pre-designed electronic map. The position information was obtained in real time using the DGPS and the machine vision. The electronic map contained a position database of crops automatically constructed when seeding. The developed system was tested on an experimental field of Seoul National University. Success rate of the spraying was about 61%.

• Journal of Ecology and Environment
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• 제36권3호
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• pp.167-172
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• 2013

A Two-year field experiment was carried out in 2009 and 2010 to evaluate the effects of different densities of wild oat and nitrogen (N) rates on oilseed rape yield and yield components. Experimental design was split plot with three replications. Increased nitrogen rates up to 150 kg N/ha caused an increase in oilseed rape grain yield in weed-free plots (4.26 t/ha; 1t = $10^3kg$), while even at the lowest density of wild oat (15 $plants/m^2$), increasing N fertilizer only up to 50 kg/ha led to a significant increase in grain yield. Wild oat growth was favored by high levels of N. Intraspecific competition reduced biomass, 100-seed weight and number of tillers of wild oat. Both lower N rate and intraspecific competition had negative effect on wild oat growth but the weed was still able to produce a considerable number of tillers and vigorous seeds. It showed that wild oat possess a notable adaptive plasticity and can allocate a greater proportion of its resource toward reproductive organs even under resource shortage conditions and, thus, it may increase the competitive ability of the weed over the crop.Our results suggest that effective weed management should be done to prevent wild oat seed production in crops preceding oilseed rape as well as to control the weed at early season in oilseed rape fields.