• Weed & Turfgrass Science
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• 제7권1호
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• pp.46-53
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• 2018

본 시험은 논, 밭, 과원(비농경지 포함)에서 주로 발생하는 잡초의 생체중과 건물중을 비교하여 무처리 최소 총 발생량의 생체중에 대한 기초 자료를 확립하고자 10개 지역에서 시험을 수행하였다. 논 포장의 일년생잡초인 피의 건물률 평균은 14.8%, 일년생잡초(피 포함) 건물률 평균은 12.5%, 다년생잡초 건물률 평균은 13.9%로 나타났다. 밭 포장의 일년생잡초의 건물률 평균은 20.1%로 나타났으며, 과원(비농경지 포함)포장 내 일년생 및 다년생잡초 총계의 평균은 18.4%로 나타났다. 이에 따라, 생체중에 대한 무처리 최소 총발생량은 논 포장에서는 피 $210g\;m^{-2}$, 일년생잡초(피 포함) $400g\;m^{-2}$, 다년생잡초 $220g\;m^{-2}$로 제시할 수 있다. 또한, 밭 포장에서는 일년생잡초 $250g\;m^{-2}$, 과원(비농경지 포함) 포장에서는 일년생 및 다년생잡초 총계 $550g\;m^{-2}$으로 제시할 수 있다.

• Journal of Biosystems Engineering
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• 제27권2호
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• pp.133-142
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• 2002

This is a fundamental study to develop a sensor to detect weeds in paddy field using machine vision adopted spectralphotometric technique in order to use the sensor to spread herbicide selectively. A set of spectral reflectance data was collected from dry and wet soil and leaves of rice and 6 kinds of weed to select desirable wavelengths to classify soil, rice and weeds. Stepwise variable selection method of discriminant analysis was applied to the data set and wavelengths of 680 and 802 m were selected to distinguish plants (including rice and weeds) from dry and wet soil, respectively. And wavelengths of 580 and 680 nm were selected to classify rice and weeds by the same method. Validity of the wavelengths to distinguish the plants from soil was tested by cross-validation test with built discriminant function to prove that all of soil and plants were classified correctly without any failure. Validity of the wavelengths for classification of rice and weeds was tested by the same method and the test resulted that 98% of rice and 83% of weeds were classified correctly. Feasibility of CCD color camera to detect weeds in paddy field was tested with the spectral reflectance data by the same statistical method as above. Central wavelengths of RGB frame of color camera were tried as tile effective wavelengths to distingush plants from soil and weeds from plants. The trial resulted that 100% and 94% of plants in dry soil and wet soil, respectively, were classified correctly by the central wavelength or R frame only, and 95% of rice and 85% of weeds were classified correctly by the central wavelengths of RGB frames. As a result, it was concluded that CCD color camera has good potential to be used to detect weeds in paddy field.

• Mycobiology
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• 제30권2호
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• pp.96-101
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• 2002

Four pathogenic fungal isolates belonging to different genera including Alternaria, Fusarium and Curvularia were isolated from selected diseased weeds growing in the fields in Dakahalia district. The inoculum of these pathogenic fungi specific to weeds were cultured, standardized and formulated as alginate pellets containing mycelium plus culture filtrate. These mycoherbicides were evaluated for disease severity(DS). Maximum DS was obtained with the alginate pellets of mycelium filtrate Fusarium solani. Physiological changes of the treated weed were determined 5 aiid 10 days after treatments. As compared to the healthy weeds, all mycoherbicide formulations significantly decreased the amount of photosynthetic pigments and subsequently soluble and insoluble sugars in the infected weeds. The mycoherbicide formulation of F. solani had the greatest effect on lowering to the abovementioned amount in the leaves of Chenopodium murale. Generally, treatment of weed leaves with the specific mycoherbicide led to a highly significant increase in total phenol content when compared to the healthy control weed. C. murale infected with the mycoherbicide formulation of F. solani had higher levels of phenolic compounds than those other treated weeds particularly after 10 days of inoculation.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.15-18
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• 2003

Contemporary biological control system includes the use of fungi to control weeds in agricultural ecosystems and forests. Fungal pathogens of weeds that are highly virulent and specific to target weeds, and able to be produced massively by artificial culture could be applied like chemical herbicides over the weeds.(중략)

• The Plant Pathology Journal
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• 제39권4호
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• pp.374-383
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• 2023

Capsicum annuum (CA) is grown outdoors across fields in Jeollabuk-do, South Korea. The weeds surrounding these fields were investigated regarding the infection of 11 viruses infecting CA during the year 2014-2018. In the reverse transcription polymerase chain reaction diagnosis, 546 out of 821 CA samples (66.5%) were infected by nine viruses, and 190 out of 918 weed samples (20.7%) were infected by eight viruses. Correlation analysis of the mutual influence of the viruses infecting CA and weeds during these 5 years showed that five viruses had significant positive correlations with the infection in both CA and weeds. Over the study period, the weeds infected by cucumber mosaic virus (CMV) in the previous year were positively correlated with the incidence of CMV infection in CA in the current year, although the correlation was lower for tomato spotted wilt virus (TSWV) compared to CMV. The CMV infection percent was 14.0% in summer annuals, 11.4% in perennials, and 7.8% in winter annuals. However, considering the overwintering period without CA, the infection percent was 5.2% higher in winter annuals and perennials than that in summer annuals, indicating that winter annual and perennial weeds served as the main habitats for insect vectors. The TSWV infection percent in weeds was 10.4% in summer annuals, 6.4% in winter annuals, and 6.2% in perennials. The weeds surrounding CA fields, acting as the intermediate hosts, were found to be the potent sources of infection, influencing the spread and diversity of CA-infecting viruses. The results of this study can contribute to prevent viral infection in agricultural fields.

• 한국환경과학회지
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• 제5권6호
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• pp.801-812
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• 1996

We investigated concentrations of heavy metals(Cr, Cd, Zn, Fe, Pb, Cu, and Mnl and correlations between concentrations of heavy metals in the sediment, soil, weeds, and vegetables on the lower Nakdong river. Concentrations of heavy metals on the lower Milyang river was generally lower than those of other sampling area. In the soil, concentration of Pb is generally larger than that of other heavy metals. Generally, concentrations of heavy metals in the sediment show decreasing tendency 8s the sampling area moves toward downstream of the river, but those of in the soil and weeds show increasing tendency. There is no significant correlation between concentration of heavy metals in the soil-sediment, soil-vegetables, sediment-weeds, or vegetables-weeds. Only concentrations of Pb in the vegetables and those of in the weeds show very high correlation.

• Journal of Ginseng Research
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• 제23권3호
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• pp.135-147
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• 1999

Nine herbicide products (fluazifop-p-butyl, clethodim, MCPA-sodium, 2,4-0 amine, chlorthal dimethyl, diquat, glyphosate, ethalfluralin and oryzalin) were evaluated for use on ginseng (Panax quinquefolius). Products varied in their ability to suppress weeds and certain materials were phytotoxic to ginseng in some trials. Chlorthal dimethyl (broadleaf weeds), MCPA-sodium (broadleaf weeds), fluazifop-p-butyl (grass weeds), and clethodim (grass weeds) were found to be effective as weed control agents and did not adversely affect ginseng growth. Other products tested were either not efficacious or were phytotoxic to ginseng in some trials. Weed populations were mainly introduced into the planting sites via the straw mulches used in ginseng cultivation.

• 농약과학회지
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• 제12권1호
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• pp.1-8
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• 2008

최근 한국 논에서는 1989년부터 pyrazosulfuron/molinate 및 bensulfuron/molinate와 같은 "일발처리제"의 광범위한 사용으로 설포닐우레아(SU)계 제초제 저항성 잡초들이 급증하고 있다. 2008년 현재까지 확인된 SU계 제초제 저항성 잡초들은 일년생 잡초 7초종과 다년생 잡초 3초종이 각각 확인되었다. 현재까지 개발 및 사용되어온 SU계 제초제들과 화본과 전용 제초제들이 혼합된 "일발처리제"로부터 제초제 저항성 잡초 방제를 위주로 한 새로운 제초제 개발이 요구된다. 최근 한국과 농업적 환경이 유사한 일본은 제초제 저항성 잡초를 방제하기 위한 시스템으로 제초제 개발이 급변하고 있다. 따라서 한국에서도 제초제 전문약제들이 혼합된 3종 이상의 새로운 "일발처리제" 개발로 전환되어 져야 한다. Benzobicyclone, bromobutide, cafentrazone, pyrimisulfam은 SU계 제초제 저항성 잡초에 효과적인 제초제들이다. 그러나 이들 제초제 전문 약제들에 대한 제초제 저항성 잡초 초종별 반응은 서로 다르게 나타났는데, bromobutide와 cafentrazone은 각각 사초과와 광엽잡초에 효과적이나 benzobicyclone과 pyrimisulfam은 사초과와 광엽잡초에 모두 효과적이다.

• 한국초지조사료학회지
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• 제21권2호
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• pp.103-108
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• 2001

This study was carried out to investigate the introduced route of exotic weeds and the effects of herbicide treatment. Herbicide trial was arranged as a completely randomized block design with treatment 1(\circled1 Dicamba $1\ell$/ha, \circled2 Mecoprop $5\ell$/ha, \circled3 Bentazone $3\ell$.ha, \circled4 Glyphosate $4\ell$/ha and \circled5 Pyrazosulfuron-ethyl 2kg/ha), and treatment 2(\circled1 Dicamba $2\ell$/ha, \circled2 Dicamba $4\ell$/ha, \circled3 Glyphosate $6\ell$/ha, \circled4 Glyphosate 4+Dicamba $1\ell$/ha and \circled5 Glyphosate 4+dicamba $2\ell$/ha) against 10 exotic weed species, and conducted in Suwon, Seosan and Yeongam from 1997 to 1999. Exotic weeds have been mostly introduced within imported cereals for concentrate feed or within seeds for forage production. Most of exotic weeds in forage crop field were controlled more than 95% by herbicide, but it was desirable that the control of exotic weeds was abreast of chemical and ecological method.

• Journal of Mechanical Science and Technology
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• 제20권10호
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• pp.1576-1589
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• 2006

Most of surface water ways in Egypt suffer from the infestation of aquatic weeds especially submerged ones which cause lots of problems for the open channels and the water structures such as increasing water losses, obstructing the water flow, and reducing the efficiency of the water structures. Accurate simulation of the water flow behavior in such channels is very essential for water distribution decision makers. Artificial Neural Network (ANN) has been widely utilized in the past ten years in civil engineering applications for the simulation and prediction of the different physical phenomena and has proven its capabilities in the different fields. The present study aims towards introducing the use of ANN technique to model and predict the impact of the existence of submerged aquatic weeds on the hydraulic performance of open channels. Specifically the current paper investigates utilizing the ANN technique in developing a simulation and prediction model for the flow behavior in an open channel experiment that simulates the existence of submerged weeds as branched flexible elements. This experiment was considered as an example for implementing the same methodology and technique in a real open channel system. The results of current manuscript showed that ANN technique was very successful in simulating the flow behavior of the pre-mentioned open channel experiment with the existence of the submerged weeds. In addition, the developed ANN models were capable of predicting the open channel flow behavior in all the submerged weeds' cases that were considered in the ANN development process.