• Title/Summary/Keyword: Weeds

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Removal of Herbicide Molinate during treatment Processes for Drinking Water (상수처리과정 중 제초제 molinate의 제거)

  • Park, Ju-Hwang;Park, Jong-Woo;Kim, Jong-Soo;Kim, Jang-Eok
    • Applied Biological Chemistry
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    • v.45 no.3
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    • pp.145-151
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    • 2002
  • Molinate, a thiolcarbamate herbicide widely used for control weeds in paddy soil, has been suspected for a possibile transportation into surface water due to its relatively high solubility in water. This study was performed to know that how much molinate could be removed during treatment processes for drinking water. The removal effciency of molinate in water was negligible in treatment process of polyaluminium chloride for coagulation. Molinate was gradually decreased up to 60.2% during contact time of 4 hours when chloride, an disinfectant used in water treatment system was treated. And in an hour treatment of ozone, molinate removal ranged $28.9%{\sim}58%$ However by treatment system of granular activated carbon, molinate was removed 93.9 to 100% at all concentrations used with a range of concentrations of granular activated carbon treated. The removal effciency of whole system simulated with removal efficiencies of molinate in each step of treatment processes was 99.5%. Therefore, if molinate happen to come into water treatment facilities, it could be removed effectively through the treatment processes.

Meteorological Impact on Daily Concentration of Pollens in Korea (일별 꽃가루농도에 대한 기상영향)

  • Lee, Hye-Rim;Kim, Kyu-Rang;Choi, Young-Jean;Oh, Jae-Won
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.3
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    • pp.99-107
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    • 2012
  • There has been increasing number of patients with asthma, rhinitis, and conjunctivitis due to the atmospheric pollution and global warming. In this study, we investigated daily observed number of pollens to establish a standardized method for the impact analysis of the climate changes on the number of daily pollens in Korea. Daily observed allergenic pollens of trees, weeds, and pine were analyzed during the period of 1998 to 2010 (except 2006) in Seoul, Busan, Daegu, Gwangju, Gangneung, and Jeju. They increased in large cities including Seoul during the last 12 years and the long-term trend may continue in the future. Daily concentration or amount of pollens was highly correlated with weather variables. Positive correlation was found between air temperature and the pollens although different relationships existed for different locations. Chill days were utilized to estimate the length of the flowering or pollen period. The pollen period of trees was shorter in the field when the winter temperature was low. This approach may be utilized to determine the quantitative change in length of the pollen season in the future.

Monitoring of pesticide residues at alpine and sloped-land in Gangwondo, Korea (강원도 고랭지 배추경작지의 토양 및 수질 중 농약 오염 실태)

  • Park, Dong-Sik;Kim, Tae-Han;Kim, Seong-Soo;Lee, Sang-Min;Kim, Song-Mun;Hur, Jang-Hyun
    • The Korean Journal of Pesticide Science
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    • v.8 no.3
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    • pp.189-197
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    • 2004
  • Alpine and sloped-land in Gangwondo, Korea is the most important land type for cultivation of Chinese cabbage. However, farmers in these regions have major problems with insect pests, weeds and disease. Over use or inappropriate use of agrochemicals occurs frequently. No intensive study of pesticide contamination in this area has been done. The work presented in this paper addresses this deficiency. We measured pesticide residues within soil and water samples using multiresidue analysis. Samples were collected bimonthly from April to October, 2002 at three sites with to sampling spots. At the three sites, Pyeongchang, Jeongseon and Taebaeck, pesticides most frequently detected (>30% of samples) in soil samples were endosulfan, fluazinam, diniconazole, alachlor, prothiofos and dimethomorph. The amount of pesticide residues in the soils was ranged from 0.004 to $0.412\;mg\;kg^{-1}$ in these samples. Non-registered pesticides were also detected in these samples, indicating illegal use of pesticides. No pesticide were detected in the water samples collected from those sites. The results showed that pesticide residues might be dependant on physiochemical properties of pesticides, application history and soil properties. This study provides basic data for appropriate pesticide use on alpine and sloped-land in Korea.

Selection of Low Toxic Pesticides and Residual Toxicity to Cotesia glomerata (배추나비고치벌 (Cotesia glomerata)에 대한 저독성 약제 및 잔류독성)

  • Choi, Byeong-Ryeol;Lee, Si-Woo;Park, Hyung-Man
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.251-259
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    • 2007
  • For the development of integrated pest management system by harmonizing biological and chemical control, some experiments wee carried out to select low toxic pesticides against natural enemies. and their residual toxicity were evaluated. Leaf dipping method, body dipping method, and diet treatment method were set up for the toxicity evaluation against Cotesia glomerata adults. We had tested 46 different pesticides (31 insecticides, 11 fungicides, 4 herbicides) at recommending concentration commonly used to control diamond back moth, disease and up-land weeds in chinese cabbage field. Twenty three insecticides, eleven fungicides, and four herbicides were shown to be low toxic to C. glomerata adults in the treatment of body dipping. After insecticide spraying at recommending dose on the chinese cabbage, we examined residual effect of insecticides by introducing natural enemies on different days. Safety interval for the introduction of C. glomerata adults was established according to the residual toxicity of pesticides. Safe insecticides for the introduction of C. glomerata adults at one day after treatment (DAT) were thiacloprid, acephate, chlorfenapyr, clothianidin and at 3 DAT were imidacloprid, deltamethrin, thiamethoxam, dimethylvinphos, emamectin benzoate.

Effects of Rainfall Events on Soil in Orchard Field under Herbicide Treatment. 2. Characteristics of Runoff and Soil Erosion (제초제 처리 과수원 포장에서 강우 사상의 효과. 2. 유거와 토양침식의 변화)

  • Chung, Doug-Young;Park, Mi-Suk;Lee, Kyu-Seung;Lee, Jin-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.1
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    • pp.36-43
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    • 2010
  • Changes in runoff and soil erosion at slightly hilly erosive plots with pear trees over a three-year period were monitored under two distinct types of weed treatment by herbides : (1) pre-emergence herbicide with glyphosate; (2) post-emergence herbicide with paraquat. The numbers of rainfall events from June to Nov for three years of experimental periods were approximately 50 times in the plots having 5.5%to 10.2%slope at an altitude of 125 m. The steady-state infiltration rate was generally increased in the bare plot from which all weeds were removed while it was decreased in the herbicide treated plots and control. The runoffs from the control plot during the experimental periods were always less than those from plots of the herbicide-treated and the bare. The runoff under the same rainfall intensity was decreased in the order of bare, glyphosate, paraquat, and control. This results indicated that the removal time of weed by the different types of herbicides might influenced the runoff rate. For the first two years of the experimental periods, loss of fine fraction was much greater than that of coarse fraction while soil loss was correlated neither with total rainfall nor amount of runoff. The soil erosion rate under the same rainfall intensity was increased in the order of control, glyphosate, paraquat, and bare plot. However, there were not much differences in the soil loss for all plots under a relatively lower rainfall intensity less than 30 mm $day^{-1}$, resulting in rainfall intensity was important factor on soil erosion.

Characterization of Fusarium udum Causing Fusarium Wilt of Sunn Hemp in Korea (클로탈라리아 시들음병을 일으키는 Fusarium udum의 특성)

  • Choi, Hyo-Won;Hong, Sung Jun;Hong, Sung Kee;Lee, Young Kee;Kim, Jeomsoon
    • The Korean Journal of Mycology
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    • v.46 no.1
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    • pp.58-68
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    • 2018
  • Sunn hemp (Crotalaria juncea) is used as a nitrogen-fixing green manure in Korea to improve soil quality, reduce soil erosion, and suppress weeds and nematodes. In 2014, wilting sunn hemp plants were observed in green manure-cultivated fields in Wanju, Korea. Leaves of the infected plants began yellowing, starting with the lower leaves, eventually leading to their death. Moreover, a number of dark perithecia were observed on the wilting stems. Six isolates were obtained from these perithecia by single spore isolation. Based on their morphological characteristics, the isolates were identified as Fusarium udum (teleomorph: Gibberella indica). Macroconidia were slightly curved with almost hooked apical cell, and microconidia were formed on false heads by monophialides. Chlamydospores were produced abundantly in the hyphae, either singly or in clusters. To confirm the identification, multilocus sequence analysis was conducted using translation elongation factor 1 alpha (TEF), calmodulin (CAL), and histone 3 (HIS3). The sequences of TEF, CAL, and HIS3 showed 94.4~96.2%, 99.7%, and 99.6~99.8% similarity to the reference sequences of F. udum in NCBI GenBank, respectively. Pathogenicity was tested on sunn hemp and two soybean cultivars using the inoculation method of soil drenching with spore suspension. The wilting symptoms were observed only in sunn hemp and one cultivar of soybean (cv. Teagwang) after 14~21 days of inoculation. This is the first report of wilt disease in sunn hemp caused by Fusarium udum in Korea.

Effect of Herbicide Combination on Agronomic Characteristics, Dry matter Yield, Nutritive Value and Weed Control of Silage Corn in Alpine Area (고랭지에서 제초제 조합에 의한 사일리지용 옥수수의 생육특성, 건물수량, 사료가치 및 잡초방제에 미치는 영향)

  • Lee, J.K.;Park, H.S.;Chung, J.W;Na, K.J;Kim, Y.G.;Seo, S.;Sung, K.I.;Jung, J.R.;Cho, K.S.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.24 no.1
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    • pp.37-42
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    • 2004
  • This study was conducted to select the optimum herbicide combination on agronomic characteristics, dry matter yield, nutritive values and weed control of the silage corn at Daekwanryong branch(altitude 800m a.s.1.) of National Livestock Research Institute from 2001 to 2002. The treatments consisted of control, metolachlor, thiobencarb+linuron, pendimethalin, pendimethalin+linuron, propisochlor, nicosulfuron, propisochlor+nicosulfuron, and non treatment. The plant height and ear height of corn were no significant different among herbicide combination. However, the highest dry matter(DM) and ear rate of silage corn were observed with nicosulfuron treatment; 31.4% and 52.7%, respectively. Also, Dry matter yield of silage corn was the highest of 16,503kg/ha with propisochlor+nicosulfuron(P<0.05). The control of annual weeds was the greatest of 96.4% in the plots of propisochlor+nicosulfuron application. These results indicate that propisochlor+nicosulfuron treatment would be the optimum combination for dry matter yield, weed control and nutritive value of silage corn in alpine area.

Mode of Action of the New Diphenyl Ether Herbicide KC6361 (새로운 백화형 디페닐에테르계 화합물 KC-6361의 제초작용기작)

  • Kim, J.S.;Kim, T.J.;Kim, Y.S.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.14 no.2
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    • pp.81-93
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    • 1994
  • This study was conducted to characterize herbicidal activity of the new type diphenylether compounds inducing bleaching(whitening) in relation to their chemical structures and to find out the herbicidal action mechanism. Bleaching was highly appeared in the compounds which have short chain alkyl or allyl group of cabamoyl type in meta position of A ring and nitro group in para position of B ring, and KC6361 showed the highest efficacy among these derivatives. Rice was tolerant to KC6361 at 2.0kg/ha. The applications of this compound at 0.25~1.0kg/ha provided acceptable control of the various weeds including large crabgrass, barnyardgrass, pigweed and so on. In the dark condition, KC6361 decreased carotenoid contents but increased chlorophyll in etiolated cucumber cotyledon. By the increase of light intensity, the carotenoid biosynthesis was more inhibited than the chlorophyll biosynthesis. The incorporation of $C^{14}$-acetate into lipid was slightly inhibited. Both KC6361 and norflurazon stimulated growth of dwarf rice(cv. Daneunbanju). These results suggest that both KC6361 and norflurazon may have the same action sites. To confirm this hypothesis, the changes of carotenoid intermediates in cucumber cotyledon and barnyardgrass leaf treated with KC6361 were investigated. Phytoene and phytofluene were increased but ${\beta}$-carotene was decreased, indicating that KC6361 inhibited phytoene and/or phytofluene dehydrogenase like norflurazon.

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Phytosanitary Management of Dodder Seeds (Cuscuta spp.) Mixed in the Imported Seeds with the Dry Heat-treatment (수입종자에 혼입된 새삼속 종자의 건열처리에 의한 관리 방안)

  • Kyoung, Eun-Seon;Moon, Kwang-Ok;Oh, Jin-Bo
    • Weed & Turfgrass Science
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    • v.5 no.1
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    • pp.10-16
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    • 2016
  • Proper actions such as discard, return or manufacturing should be taken to imported plants contaminated with quarantine weeds. Heat-treatment has been used as a processing method in many countries such as U.S., Australia, Canada as well as Korea. This study was carried to find appropriate heat-treatment methods for devitalizing dodder seeds mixed with plant seeds. Two species of dodder seeds and six imported seeds were treated for 1, 5, 10, 15, 30, 45 minutes or 1, 2, 4, 5, 6, 8 hours at the temperatures of $75^{\circ}C$, $80^{\circ}C$, $85^{\circ}C$, $90^{\circ}C$, $95^{\circ}C$, $100^{\circ}C$ and $120^{\circ}C$. According to the study, dodder seeds were devitalized at the conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes, $95^{\circ}C$ and $100^{\circ}C$ for 15 minutes, $110^{\circ}C$ for 10 minutes and $120^{\circ}C$ for 5 minutes. Meanwhile, seed vigours of Cosmos bipinnatus and Callistephus chinensis had no difference when compared with untreated control at the heat-treatment conditions of $85^{\circ}C$ for 2 hours, $90^{\circ}C$ for 30 minutes.

The Comparative Study on Food Consumption Patterns, Dietary Behavior, and Nutrition Knowledge of Korean Professional Soccer Players and Non-athletic Males (일부 프로 축구선수들과 성인 남성의 식품섭취패턴, 식습관 및 영양지식에 관한 비교 연구)

  • Kim, Hye-Kyeong;Kwon, Jong-Sook;Kim, Chan;Kim, Jun-Ho;Kim, Chul-Hyun;Kim, Kyung-Min
    • Korean Journal of Community Nutrition
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    • v.13 no.2
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    • pp.164-175
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    • 2008
  • This study was performed to compare food consumption patterns, dietary behavior, and nutrition knowledge between Korean professional soccer players and the non-athletic males. Data were collected from 53 soccer players working for Korean professional soccer clubs and 44 non-athletic males, using self-administered questionnaires. There were significant differences in food consumption frequency between two groups. Meats and eggs, fishes and shellfishes, sea weeds were consumed more frequently by the soccer players. The frequency scores of foods rich in iron, calcium, and protein were also higher in the soccer players compared with the non-athletes. Meanwhile, the consumption of alcohol was more frequent in the non-athletes. As for the cooking method, the soccer players showed higher preference for steaming/parboiling and consumed raw vegetables and fruits more frequently than the non-athletic males (p < 0.05). The average scores of soccer players on nutrition knowledge for basic nutrition and athletic nutrition were lower than the respective values of the non-athletic males. However, the soccer players showed better eating behaviors and dietary habits compared with non-athletic males (p < 0.001). They had well-balanced, regular diet and good habits for chronic disease prevention. No significant relationship could be observed with respect to nutrition knowledge and nutritional behavior. Moreover, the experience of getting nutrition information did not affect either nutrition knowledge score or nutritional habits score, except that for habits of chronic disease prevention in non-athletes. Therefore, it is suggested that more effective and practical nutrition education program be needed for promoting healthy eating habits and improving nutritional status in young males.