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Toxicological Effects of Some Insecticides against Welsh Onion Beet Armyworm (Spodoptera exigua) (Metaflumizone을 포함한 몇 가지 약제의 파밤나방(Spodoptera exigua)에 대한 독성검정)

  • Kang, E.J.;Kang, M.G.;Seo, M.J.;Park, S.N.;Kim, C.U.;Yu, Y.M.;Youn, Y.N.
    • Korean journal of applied entomology
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    • v.47 no.2
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    • pp.155-162
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    • 2008
  • The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.

Persistence of Chlorfenapyr in Paprika Leaf and Its Residual Biological Activity to Two Spotted Spider Mite, Tetranychus urticae (파프리카 잎 중 Chlorfenapyr의 잔류량 변화와 점박이응애에 대한 잔효 생물 활성)

  • Cho, Kyu-Song;Lee, So-Jung;Lee, Dong-Yeol;Kim, Yeong-Jin;Kim, Kyoung-Youl;Chung, Bu-Keun;Kang, Kyu-Young
    • The Korean Journal of Pesticide Science
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    • v.15 no.3
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    • pp.317-322
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    • 2011
  • A comparative experiment was conducted to investigate the persistence of chlorfenapyr residue and its biological activity to two spotted spider mite, Tetranychus urticae, after treatment of chlorfenapyr suspension concentrate (10% SC) on paprika plants at recommended (2000 times dilution) and double dosage. Biological half-lives of chlorpfenapyr were estimated as 8 and 5 days in leaves and fruits of paprika plants, respectively. While initial deposits of chlorfenapyr residues in leaves at recommended and double dosages were 22.22 and 37.75 ${\mu}g\;g^{-1}$ at the time of application, its residue decreased to 1.56 ${\mu}g\;g^{-1}$ and 3.62 ${\mu}g\;g^{-1}$ at 29 days after treatment, respectively. Residual biological activity of chlorfenapyr SC to T. urticae at recommended dosage lasted for 7 or 15 days on the basis of 24 or 48-hrs mortality test assayed with feeding on excised leaf chlorfenapyr-treated. The control efficacy to the mite showed a good agreement with the persistence of chlorfenapyr residues in leaves.

The Absorption and Metabolism of Fenobucarb and Carbofuran by Susceptible and Carbamate Insecticide-selected Strains of the Brown Planthopper (Nilaparvata lugens Stal) (Fenobucarb 및 Carbofuran의 저항성 벼멸구 체벽 투과량과 체내대사에 관한 연구)

  • 박형만;이영득;최승윤
    • Korean journal of applied entomology
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    • v.30 no.1
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    • pp.10-17
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    • 1991
  • Cuticular penetration and detoxication as mechanisms of resistance to the carbamate insecticides in fenobucarb-selected($R_{f}$) and carbofuran-selected($R_{c}$) strains of the brown planthopper (N. lugens Stal) were investigated. Rates of penetration were not significantly different in the susceptible and resistant strains. However, total amount of excretion of the $R_{f}$ and $R_{c}$ strains were much larger than that of the susceptible strain. Fenovucarb and carbofuran were in vivo metabolizd much faster in the $R_{f}$ strain than in the susceptible strain. OSBP(o-sec-butyl phenol) and 3-ketocarbofuran phenol were invitro the major metabolites of fenobucarb and carbofuran in the brown planthopper, respectively. Total amount of the two major metabolites were produced abotu 2 times larger in the $R_{f}$ and $R_{c}$ strains compared to the susceptible strain. OSBP and 3-ketocarbofuran phenol were not so toxic to the brown planthopper ($LD_{50}$ >100 $\mu\textrm{g}$/g hopper). Based on our data, detoxication plays a large role in resistance to fenobucarb and carbofuran in the resistant strain of BPH, although several resistance factors maybe involved.

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An Analysis on the Prevention Effects of Forward and Chain Collision based on Vehicle-to-Vehicle Communication (차량 간 통신 기반 전방추돌 및 연쇄추돌 방지 효과 분석)

  • Jung, Sung-Dae;Kim, Tae-Oh;Lee, Sang-Sun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.36-43
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    • 2011
  • The forward collision of vehicles in high speed can cause a chain collisions and high fatality rate. Most of the forward collisions are caused by insufficient braking distance due to detection time of driver and safe distance. Also, accumulated detection time of driver is cause of chain collisions after the forward collision. The FVCWS prevents the forward collision by maintaining the safety distance inter-vehicle and reducing detection time of driver. However the FVCWS can cause chain collisions because the system that interacts only forward vehicle has accumulated detection time of driver. In this paper, we analyze forward and chain collisions of normal vehicles and FVCWS vehicles on static traveling scenario. And then, we analyze and compare V2V based FVCWS with them after explaining the system. The V2V FVCWS reduces detection time of driver alike FVCWS as well as remove accumulated detection time of driver by broadcasting emergence message to backward vehicles at the same time. Therefore, the system decrease possibility of forward and chain collisions. All backward normal vehicles and 3~4 backward FVCWS vehicles have possibility of forward and chain collisions in result of analysis. However V2V FVCWS vehicles almost do not chain collisions in the result.

The Effect of Sosokmyung-tang extract on Global cerebral ischemia·Cerebral Infarction by MCA occlusion in vivo (소속명탕(小續命湯) 추출물(抽出物)이 전뇌허혈(全腦虛血)및 국소뇌허혈(局所腦虛血)에 미치는 영향(影響))

  • Lee, Kyung-Ae;Shin, Gil-Cho;Lee, Won-Chul
    • The Journal of Dong Guk Oriental Medicine
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    • v.8 no.1
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    • pp.107-116
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    • 1999
  • The effects of Sosokmyung-tang(小續命湯) on global cerebral ischemia and cerebral in farction by MCA(middle cerebral artery) occlusion were evaluated in this study. This study was performed to investigate that Sosokmyung-tang would be useful for cerebrovascular diseases. In the case of global cerebral ischemia, ICR mice were used and divided into three group at random. Control group was treated after oral administration of normal saline, experimental group was treated after oral administration of 10.4mg/20g/day of Sosokmyung-tang extract. The multiple parameter of global cerebral ischemia included the duration of coma of KCN(potassium cyanide)-injected(1.2mg/kg, i.v) group and the survival time of KCN-injected(3.0mg/kg, i.v) group. In the case of cerebral infarction by MCA occlusion, Sprague-Dawley rats were used and divided into three group at random. Control group was given nothing before MCA occlusion, experimental group was given 157.2mg/250g/day of Sosokrnyung-tang extract before MCA occlusion. We investigated edema and ischemic ratio in 8 slices of rats' brain after MCA occlusion. The results were obtained as follows : 1. Sosokrnyung-tang significantly shortened the duration of coma of KCN-injected(1.2mg/kg,i.v) group and lengthened the survival time of KCN-injected(3.0mg/kg, i.v) group. 2. Sosokmyung-tang significantly decreased cerebral edema and ischemic ratio in rats after MCA occlusion. From the above results, it was concluded that Sosokmyung-tang can be effectively applied to cerebrovascular diseases.

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Bioassay of Environment-friendly Insecticides for Management of Mosquito, Culex pipieos molestus (지하집모기 (Culex pipiens molestus)의 방제를 위한 환경친화적 살충제의 생물검정)

  • Choi, Su-Yeon;Oh, Se-Chan;Cho, Min-Su;Paek, Seung-Kyoung;Kim, Jin-Su;Kim, Da-A;Gil, Mi-Ra;Youn, Young-Nam;Yu, Yong-Man
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.261-267
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    • 2007
  • Bioassay of mosquito, Culex pipiens molestus, larva was investigated by several environment-friendly insecticides. These insecticides were Novaluron as chitin synthesis inhibitor, Metho-xyfenozide as ecdysone agonist, Pyriproxyfen as juvenile hormone mimic, and Spiromesifen as lipid biosynthesis inhibitor. The 50% lethal concentration $(LC_{50})$ of these insecticides were 0.00039, 0.07193, 0.65006 and 0.04839 ppm, respectively. Novaluron has lower concentration than any other insecticide. To determine the treatment time against larval stages, insecticides were applied to different larval stages of C. pipiens molestus. Mortality ratios of mosquito larva treated with Novaluron were 100.0, 84.5, 71.0 and 48.5% on 2, 4, 7 and 10 days after hatching from eggs, respectively. Otherwise, with the other insecticides, mortality ratios were under 80% with 2 days old larva. When exposure periods were tested to 3 or 4 days old larva against 4 insecticides, at least 3 hours were needed to 100% control effect against Novaluron, and over 12 hours with other insecticides.

Repellent and Acaricidal Activities against Leptotrombidium pallidum Larvae of Eucalyptus Oil (털진드기 유충에 대한 유칼립투스 오일의 기피 및 살비활성)

  • Jo, Hyeong-Chan;Kim, Kwang-Ho;Lee, Sang-Guei;Na, Young-Eun;Park, Hyung-Man
    • Korean journal of applied entomology
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    • v.47 no.3
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    • pp.287-292
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    • 2008
  • Repellent and acaricidal activities of eucalyptus oil, permethrin, and DEET against Leptotrombidium pallidum larvae, which are a vector transmitting tsutsugamushi disease, were evaluated under laboratory conditions using a filter paper impregnated method. The $LD_{50}$ values of eucalyptus oil and DEET were 0.025 and 0.018 $mg/cm^2$, respectively while that of permethrin was higher than 0.2 $mg/cm^2$. In the repellency test of these materials at 6.14 $mg/cm^2$, eucalyptus oil gave complete repellency, and the larvae crossed the treated zone killed. But permethrin showed 60% repellency at 9.20 $mg/cm^2$ and the mites croosed the zone were not killed. The percent repellency of DEET at 0.53 $mg/cm^2$ was 8.3 and 2.8 times higher than that of permethrin and eucalyptus oil, respectively. The acaricidal activities of emulsifiable concentrates-pump sprayers containing the eucalyptus oil as an active ingredient were assayed. The emulsifiable concentrates containing 1% and 3% eucalyptus oil showed weak mortality at 1 hour after treatment, while all ones containing more than 6% oil produced 100% activity against L. pallidum larvae. The mortality also increased as exposure time to the concentrates increase. These results suggest that the potential of eucalyptus oil highly expected to be used as a control or repellent agent against L. pallidum larvae may be very high.

The Effect of TBT Toxicity on Survival and Growth of Olive Flounder, Paralichthys olivaceus (넙치 생존과 성장에 미치는 TBT의 독성)

  • TAK Keon-Tae;KIM Joong Kun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.2
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    • pp.103-108
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    • 2001
  • Toxic effect of TBTO on larva flounder was studied by the use of a food-chain system in which indirect toxicity from seawater or/and plankton can be measured, Under the treatment of 0.5 ng/L TBTO, the combined effect of diets ( Chlorella and rotifer) and seawater was significant by synergism, although the sole effect from TBTO treated diets or seawater was equally not, The values of $LT_{50}$ from results of acute-toxicity experiments for juvenile flounder were estimated to be 230.0, 48.0, 24.0, 14.6, 9.3 5.5 3.0 and 1.7 hr at 1, 10, 25, 50, 100, 250, 500 and 1000 ng/L of TBTO, respectively, and $96hr-LC_{50}$ was 3.5 ng/L. From the above results, the experiments for chronic toxicity of TBTO was executed at the concentration range of $1\sim10 ng/L$. In long-term experiments for four months, the weight and the total length of the juvenile flounder in all TBTO treated experiments slowly increased when compared to control. No significant differences in the growth and survival of the juvenile flounder were found in the treatment of 1 ng/L TBTO(P>0.05), But, $90\%$ of the juvenile flounder died in 20 days under TBTO treated seawater at both concentrations of 5 and 10 ng/L, The TBTO treated on seawater was more effective and significantly different in the growth and survival of the juvenile flounder when compare with that on artificial diets (P<0.05). From the all results, TBTO should be regulated below 5 ng/L in a coast.

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Development of a New Disinfestation Method Using Methyl Bromide and PH3 in Cut Rose Fumigation (절화장미 훈증처리시 Methyl Bromide와 PH3를 이용한 새로운 살충방법의 개발)

  • Son, Ki-Cheol;Byoun, Hye-Jin;Kim, Mi-Kyoung;Yun, Jae-Gil;Kim, Eui- Young
    • Horticultural Science & Technology
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    • v.16 no.3
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    • pp.370-373
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    • 1998
  • Fumigation by combination of methyl bromide/phosphide ($MB/PH_3$) was much more effective in disinfestating the rose insect pests (Aphis gossypii, Tetranychus urticae, and Frankliniella occidentalis) than that by individual MB or $PH_3$. Fumigation for 2 hours in the chamber using ;$MB/PH_3$ at the concentration of $10/3g{\cdot}m^{-3}$ brought about 91.3% and 100% mortality in aphids and thrips, respectively. Fumigation for 3 hrs using ;$MB/PH_3$ at the concentration of 5/3 or $7/3g{\cdot}m^{-3}$ showed over 96% mortalities in mites and thrips as well as no phytotoxicity symptoms, e.g. tip burn or bent neck, in cut roses, while mortalities of mites and thrips were not influenced by increasing $CO_2$ concerntration from 0.03% to 10% or decreasing $O_2$ concentration up to 15% in fumigation chamber.

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Study on Short-term Toxicological Evaluation of Treated Landfill Leachate Using Early Stage of River Puffer Fish, Takifugu obscurus (황복 Takifugu obscurus 자치어를 이용한 침출수 단기독성 연구)

  • Park, Hoon;Han, Kyung-Nam;Kim, Hyung-Sun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.4
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    • pp.298-304
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    • 1999
  • Toxic effect of landfill leachate on the larvae and juvenile stage of the river puffer fish, Takifugu obscurus, were investigated in order to assess severity of environmental impact of leachate effluent on the general population of estuarine fishes. A short-term toxic experiment was designed to test both laboratory hatched larvae and juveniles (5, 10 and 15 mm in length) and in-situ juveniles (30 and 45 mm in length) using the leachate concentrations between 0 and 16%. Lethal concentrations of 50% mortality ($LC_{50}$) were observed using Spearman-karber Method. 24hr-$LC_{50}$ appeared at the leachate concentrations ranging from 3.03 to 8.57%, 48hr-$LC_{50}$ at 2.73 to 6.21 %, 72hr-$LC_{50}$o at 2.45 to 5.53%, and 96hr-$LC_{50}$ at 2.38 to 4.93%, respectively. Leachate concentrations between 0.69 and 1.51% induced 96hr-$LC_1$. Respiratory frequency was significantly affected even at low leachate concentrations between 0.5 and 1.0% (P < 0.05). These results suggest that the leachate effluents may cause a harmful impact on the physiology of river puffer fish, especially for younger cohorts.

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