Journal of Pesticide Science
Online ISSN : 1349-0923
Print ISSN : 1348-589X
ISSN-L : 0385-1559
Volume 15, Issue 2
Displaying 1-24 of 24 articles from this issue
  • Naohiko ISOBE, Hideo KANEKO, Kunio SHIBA, Koichi SAITO, Shigemi ITO, N ...
    1990 Volume 15 Issue 2 Pages 159-168
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    On single or repeated oral administration of 14C-labeled esfenvalerate [(S)-α-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl) isovalerate] to male and female rats and mice at 2.5mg/kg or 2.5mg/kg/day for successive 10 days, radiocarbon was rapidly and almost completely excreted into the urine and feces. 14C tissue residues after single oral administration were generally very low except for in the fat in both rats and mice. Major biotransformation reactions were 1) oxidation at the 2- and 3-positions of the acid moiety and the 2′- and 4′-phenoxy positions of the alcohol moiety, 2) cleavage of ester linkage, and 3) conjugation of the resultant carboxylic acids, alcohols and phenols with glucuronic acid, sulfuric acid, glycine or taurine. Treatment of rats and mice with single or repeated oral doses of a mixture of 14C-esfenvalerate and unlabeled [2S, αR]-, [2R, αS]- and [2R, αR]-isomers of fenvalerate [(RS)-α-cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl) isovalerate] at the equal ratio revealed that the unlabeled isomers added hardly affected 14C excretion profiles, 14C tissue residues and amounts of metabolites of esfenvalerate, indicating that esfenvalerate behaved independently of other isomers. There were no significant differences in metabolic fates between esfenvalerate and fenvalerate except that 14C fenvalerate labeled in the acid moiety showed slightly higher 14C tissue residues than esfenvalerate, due to formation of cholesteryl (R)-2-(4-chlorophenyl) isovalerate from fenvalerate but not from esfenvalerate.
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  • Kunio SHIBA, Hideo KANEKO, Noriko KAKUTA, Akira YOSHITAKE, Junshi MIYA ...
    1990 Volume 15 Issue 2 Pages 169-174
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    On a single oral dose or five consecutive oral doses of 14C-esfenvalerate [(S)-α-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate] or 14C-fenvalerate [(RS)-α-cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)isovalerate] labeled in the acid moiety to 13-day pregnant rats at rates of 2.5 and 10mg/kg/day, respectively, the maternal blood and placenta generally showed higher 14C levels as compared with the fetus and amniotic fluid. Both compounds and their metabolites did not transfer readily from the maternal blood to the fetus, the amount of 14C transferred being less than 0.07% of the dose. There were no substantial differences in the fetal 14C level and the transfer ratio (14C tissue level/14C maternal blood level) between both labeled preparations. Major 14C-compounds in the fetus, maternal blood and placenta were the parent compounds, CPIA [2-(4-chlorophenyl) isovaleric acid] and CPIA-hydroxylated derivatives and there was no qualitative difference in metabolic fates between the two compounds, except that a trace amount of CPIA-cholesterol ester [cholesteryl (2R)-2-(4-chlorophenyl) isovalerate] was detected in the maternal blood and placenta only with fenvalerate. CPIA-cholesterol ester did not seem to transfer from the maternal blood to the fetus. Overall, esfenvalerate and fenvalerate seem to behave in the same manner as far as placental transfer was concerned.
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  • Yasuhiko KONNO, Takashi SHISHIDO
    1990 Volume 15 Issue 2 Pages 175-187
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    One hundred noninsecticidal carbamates were synthesized and evaluated as synergists for fenitrothion and pirimiphos-methyl against the OP-resistant rice stem borer. Substituted aryl (including phenyl and heterocyclic groups) N, N-dimethylcarbamates had a synergistic activity. In substituted phenyl esters, the order of positional effectiveness of the substituent group on the benzene ring was parameta>ortho. 3-Methyl-4-nitrophenyl (SK-2) and 3-methyl-4-methylthiophenyl (SK-9) esters were excellent synergists. In substituted heterocyclic esters, 5-phenyl-3-isoxazolyl (SK-40) and 2-dimethylamino-6-methyl-4-pyrimidinyl (SK-102) esters were extremely effective, and the latter reduced the resistance level against pirimiphos-methyl from 1202 to 1.1-fold. When the aryl esters of N, N-dimethylcarbamate were changed to corresponding N, N-diethyl-, N, N-dimethylthio-, and N, N-dimethylthiolcarbamates, their synergistic activities decreased from 1/18 to 1/2 that of N, N-dimethylcarbamates. Aryl esters of N-methyl-, N-ethyl- and N-phenylcarbamates, and aliphatic esters of N, N-dimethylcarbamates were inactive. SK-2, -9, -40 and -102 had no synergistic activity against the susceptible strain. The synergistic mechanism of SK-102 for fenitrothion was strong inhibition of fenitroxon detoxication by binding protein and hydrolysis.
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  • Action Mechanism of the Herbicide Quizalofop-Ethyl (Part 4)
    Kunimitu NAKAHIRA, Megumi HAGA, Masaaki UCHIYAMA, Koichi SUSUKI
    1990 Volume 15 Issue 2 Pages 189-197
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    We studied relative inhibitory activities of R(+)-quizalofop {R(+)-2-[4-(6-chloro-2-quinoxalinyloxy) phenoxy] propionic acid}, its ethyl ester (quizalofop-ethyl) and oxime glycol ester (propaquizafop) on the 14C-acetate incorporation into fatty acids in excised corn leaf segments and isolated corn chloroplasts, and on acetyl-CoA carboxylase (ACC) from corn chloroplasts. Both ethyl ester (I50, 4.3×10-8M) and free acid (I50, 7.0×10-8M) showed equally high inhibitory activity on fatty acid biosynthesis in the leaf segments. On the fatty acid biosynthesis in the corn chloroplasts, however, the free acid showed a stronger inhibitory efect (I50, 3.6×10-9M) than the ethyl ester (I50, 4.1×10-7M). In further studies on the ACC from corn chloroplasts, free acid also showed more potent inhibitory activity (I50, 1.6×10-8M) than ethyl ester (I50, 1.1×10-6M) and oxime glycol ester (I50, 1.0×10-7M). In an ACC assay medium, the oxime glycol ester was hydrolyzed about 10% during 5-min incubation, while the ethyl ester was hydrolyzed about 3% during 10-min incubation. The results indicate that a hydrolyzed product in free acid form is an actual active ingredient. In addition, our previous reports and present results suggest that ACC is the primary target site of quizalofop.
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  • Studies on 2-Chloroisonicotinamide Derivatives as Rice Blast Control Agents (Part 1)
    Hiroshi YOSHIDA, Kenji KONISHI, Taizo NAKAGAWA, Shigeko SEKIDO, Isamu ...
    1990 Volume 15 Issue 2 Pages 199-203
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    N-Phenylsulfonyl-2-chloroisonicotinamide (NPSI) showed high protective systemic activity against rice blast when applied via root at a rate of more than 2.2mg a. i./50cm2 pot. The activity persisted for more than 4 weeks. NPSI was not curative in controlling the disease, however. Antifungal activity of NPSI against Pyricularia oryzae in vitro was not significant in test for spore germination, appressorial formation, appressorial penetration, mycelial growth, and melanin biosynthesis. As for the rice blast lesions appeared on the leaves of rice plants treated with NPSI, the ratio of the minute brownish lesions to the total number of blast lesions increased. Peroxidase activity was markedly enhanced in the leaves of rice plants pretreated with NPSI, when P. oryzae was inoculated. Efficacy of NPSI against rice blast decreased when abscisic acid (50ppm) was sprayed on the leaves.
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  • Experiments on Rapid Methods for Pesticide Residue Analysis (Part 1)
    Yasuo ISHII, Tuyoshi SAKAMOTO, Kenji ASAKURA, Noriyoshi ADACHI, Jun-ic ...
    1990 Volume 15 Issue 2 Pages 205-209
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    A simple and efficient cleanup procedure for gas chromatographic determination of pesticide residues was examined by the chromatographic technique using a charcoal-Florisil minicolumn. Samples were extracted with methanol, partitioned into toluene, and cleaned up with the minicolumn prior to the determination of pesticide residues by a GC-ECD and a GC-FTD. Recovery data were obtained by fortifying 15 crops with 25 pesticides at the tolerance level of each pesticide. Recoveries of 23 pesticides were higher than 90%, but those of dimethoate and oxadixyl were poor, which seemed to be due to their high polarities and an inefficient partitioning into toluene and a strong adsorption with Florisil in the elution system. Detection limits by the method were 0.01-0.02ppm for organophosphorus pesticides, 0.05ppm for carbamate and synthetic pyrethroid pesticides and 0.005ppm for organochlorine pesticides. The method was simple and applicable to the routine surveillance of various pesticide residues in many kinds of crops.
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  • Yasuo ISHII
    1990 Volume 15 Issue 2 Pages 211-216
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    A procedure for the determination of thiophanate methyl (TM) and its degradation products/metabolites in some crops is described. Residues of TM, methyl 2-benzimidazol-carbamate (MBC) and two oxygen analogues of TM (OA-1 and OA-2) were simultaneously determined by high performance liquid chromatography. A sample was first neutralized to pH 6.5-7.0 with sodium phosphate, tribasic. Compounds were extracted with methanol and partitioned into ethyl acetate. The ethyl acetate layer was washed with buffered aqueous solution (pH 6.5) to remove methanol. The ethyl acetate solution was dried and evaporated to ca. 10ml. The concentrate was poured into a deactivated alumina column and eluted with ethyl acetate and methanol-water (1:1). TM and its degradation products/metabolites were eluted with aqueous methanol and partitioned into ethyl acetate. The ethyl acetate layer was dried and evaporated to dryness. The residues were dissolved in dichloromethane and injected into HPLC. Two types of normal phase columns (Nucleosil NH2 and Partisil-10 PAC) were used with a mobile phase consisting of hexane, dichloromethane and ethanol. The minimum detectable limit with a UV detector at 254nm was ca. 5ng for TM and its degradation products/metabolites. Recovery data were obtained by fortifying tomatoes, green peppers, grapes and strawberries with TM, MBC, OA-1 and OA-2 at 0.5ppm levels. Average recoveries of TM, MBC, OA-1 and OA-2 were 75, 104, 70 and 75%, respectively.
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  • Masanori OI, Walter Curl DAUTERMAN, Naoki MOTOYAMA
    1990 Volume 15 Issue 2 Pages 217-224
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    A housefly colony collected at a sanitary land-fill was selected with diazinon for several generations in the laboratory. The resultant strain was 1400-fold resistant to diazinon (LD50: 50μg per fly) when compared to the susceptible CSMA strain. It had increased activity in each of the three enzyme systems involved in detoxification. Cytochrome P-450-dependent monooxygenases catalyzed diazinon degradation, producing diethyl phosphorothioic acid and diethyl phosphoric acid. Glutathione transferase mediating dealkylation and dearylation reactions degraded both diazinon and diazoxon. Phosphorotriester hydrolase activity for diazoxon was detected only in the resistant strain and was present in all the subcellular fractions examined. The activity was highest in the soluble fraction. The resistant strain also showed a decreased sensitivity to inhibition at the site of action, acetylcholinesterase (AChE). Interstrain comparison in AChE sensitivity using diazoxon as the inhibitor revealed ca. 6-fold difference in the bimolecular rate constant ki. An extremely high resistance of this housefly strain to diazinon may be attributable to a synergistic effect of multiple factors.
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  • Experiments on Rapid Methods for Pesticide Residue Analysis (Part 2)
    Yasuo ISHII, Noriyoshi ADACHI, Jun-ichi TANIUCHI, Tuyoshi SAKAMOTO
    1990 Volume 15 Issue 2 Pages 225-230
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    An automated GPC system was evaluated as a cleanup technique for determining pesticide residues. A sample was extracted with acetone and partitioned into dichloromethane to remove water. The extract was evaporated to dryness. The residue was cleaned up with the GPC system, using Bio-Beads SX-3 with a dichloromethane/cyclohexane (50:50, v/v) solvent system. The eluate of the GPC column was evaporated to dryness. The residue was dissolved in acetone and then injected into a gas chromatograph equipped with an alkali flame ionization detector. For cabbage, radish and soybean samples, supplemental Florisil was used in the cleanup procedure. Nineteen pesticide residues at 0.1-0.2ppm were determined in 16 crops to develop and test the method. Recoveries ranged from 75 to 110%. Detection limits by the method were 0.005-0.05ppm for 19 pesticides. This cleanup procedure using the automated GPC system is a fast and sensitive to quantify various pesticide residues simultaneously.
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  • Experiments on Rapid Methods for Pesticide Residue Analysis (Part 3)
    Yasuo ISHII, Jun-ichi TANIUCHI, Tuyoshi SAKAMOTO
    1990 Volume 15 Issue 2 Pages 231-236
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    A gas chromatographic determination for organochlorine pesticide residues in crops was examined with a Hall electrolytic conductivity detector (HECD). Samples were extracted with acetone and partitioned into hexane to remove water. The extracts were cleaned up chromatographically for gel permeation determined by HECD-GC on a DB-1 mega-borecolumn. HECD was sufficiently specific for organochlorine compounds and minimized the cleanup procedures for the determination of these compounds. Recovery data were obtained by fortifying seven crops (cabbage, radish, onion, potato, soybean, tea and brown rice) with 40 pesticides. Except for dichlorvos and flucythrinate, average recoveries ranged 73 to 119% at 0.5-10ppm fortification levels. The analytical method using both a gel permeation chromatographic cleanup and HECD-gas chromatographic detection is simple and applicable to residue analyses of various organochlorine pesticides.
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  • Keiichiro NISHIMURA, Kazuya MORI, Yoshiaki YOSHIKUNI, Toshio FUJITA
    1990 Volume 15 Issue 2 Pages 237-239
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • Kazuo KONISHI, Takashi KURAGANO, Akira NOHARA
    1990 Volume 15 Issue 2 Pages 241-244
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • Action Mechanism of the Herbicide Quizalofopethyl (Part 5)
    Kunimitu NAKAHIRA, Osamu HAYASHI, Masaaki UCHIYAMA, Koichi SUZUKI
    1990 Volume 15 Issue 2 Pages 245-247
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • Hiroyuki ANZAI, Katsuyoshi YONEYAMA
    1990 Volume 15 Issue 2 Pages 249-253
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • Mechanisms of the Antagonists
    Norio AKAIKE
    1990 Volume 15 Issue 2 Pages 255-262
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • Hiroshi HONDA, Kanju OHSAWA
    1990 Volume 15 Issue 2 Pages 263-270
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    Weevils represent a major group of pest insects for stored food products. Three important representatives were selected for our study because of their different host preference. They are: the maize weevil (Sitophilus zeamais), two bean weevils, (Callosobruchus chinensis) and (C. maculatus) and the yellow meal worm (Tenebrio molitor). The maize weevil infests several cereal grains, which are botanically quite different. The host preference is due to the emission of similar volatile ecochemicals which are responsible for the attraction of the weevil to the rice, maize and wheat. The attractants from these grains are C5-C7 fatty acids, 2-phenylethanol, 2-nonen-4-olide and nonan-4-olide. In the mating behavior of the yellow meal worm, a sex attractant and a copulation release pheromone are involved, with the former synergizing the latter. The former is (R) (+)-4-methyl-1-nonanol. Different ecochemicals are involved in the behavior of the bean weevil. In the field, the azuki bean weevil prefers only azuki bean and green gram for oviposition. Whether or not such host preference is due to ecochemicals in the plants is not known. The azuki bean weevil deposits eggs not only on the bean but also on any surface with specific curvature. On the other hand, the cow pea weevil oviposits only as a response to a chemical stimulant present in the seed coat. There are two prominant phenomena that are associated with the oviposition behavior of the two bean weevils. Under low population density conditions, the females oviposit on every among the beans, being guided by biological conditioning substance (BCS) which is deposited by the weevil on the surface of beans. Under high density conditions, a large number of eggs are randomly deposited on each bean, but only a few eggs hatch and grow normally inside each bean. The remaining eggs die by the ovicidal action of higher doses of the BCS. Thus, these weevils have developed a strategy to reduce competition among larvae and more fully utilize the host beans by using the same ecochemicals at different levels. Immediately after emerging from the beans, the azuki bean weevils begin their mating activities. A sex attractant released by the female attracts a nearby male. When they are in closer proximity, a second sex pheromone from the female induce male to erect and insert his genital organ and ejuculate. Thus, this copulation release pheromone was named “erectin” and is released from both male and female, but more from the latter. Erectin was found to consist of two synergistically acting fraction, neither having any activity. One is a mixture of several hydrocarbons of BCS; the other is (E)-3, 7-dimethyl-2-octenedioic acid. The bruchid weevils, C. chinensis and C. maculatus grow in many kinds of beans, but not in kidney beans, Phaseolus vulgaris. Extraction from kidney beans, chromatography and electrophoresis of the extract combined with bioassay for larval growth inhibition of C. chinensis using artificial beans resulted in the isolation of a growth inhibitor, a glycoprotein, whose molecular weight was ca. 48, 000 and isoelectric point, 4.46. The inhibitor was present at a level of 0.6% in kidney beans, and showed α-amylase-inhibitory activity, but it was not a trypsin inhibitor.
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  • Kouji NAKAMURA
    1990 Volume 15 Issue 2 Pages 271-281
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    In Saitama prefecture, the investigations and experiments for pesticide residue were started in 1971. Since the residue of organochlorine insecticides on crop and soil was one of problem awaiting solution at that time, the investigation into the actual condition of the residue of BHC, DDT, aldrin and dieldrin on the fields was performed at the first time. The residue amounts of all of them on soil were higher level in 1971. But, after 1 year, they decreased to about 1/2. BHC and DDT decreased with the lapse of year after 1972, but, aldrin and dieldrin were not decreased and about 0.1ppm of concentration was kept up on soil. Then, the effects of promoting decomposition on soil and suppressing absorption to crops to aldrin and dieldrin were experimented with using soil conditioner. In this experiment, 5 kinds soil conditioneres, fused magnesium phosphate, calcium carbonate, calcium cyanamide, magnesium nitrohumate and compost, were used. By application of fused magnesium phosphate and calcium cyanamide to soil, the pH of soil was rised from acidity to about neutrality, and absorption of aldrin and dieldrin to crops were increased, further, the oxidation from aldrin to dieldrin was promoted. The application of magnesium nitrohumate and compost suppressed absorption of aldrin and dieldrin by crops. The residue amounts of aldrin and dieldrin on soil were decreased by the application of fused magnesium phosphate or calcium cyanamide with compost. And, same effect was recognized in the application of magnesium nitrohumate. Since about 1975, many problems on herbicides were brought with rapid increase of used amount of herbicides. Then, the behavior of herbicides was investigated in paddy fields. In water for irrigation or drain, the detectable times of chloronitrofen, benthiocarb, molinate and simetryne were in conformity with used time in paddy fields. When, the residue on soil was experimented with pot, the residue amounts of benthiocarb and simetryne under watering condition were more little than under flooding condition. Then, the leaching tests of several herbicides were performed with lysimeter. In this experiments, it became clear that the amounts of herbicides moving to a lower soil layer and leached out increased with the increase in water solubility of the herbicide. In 1976, the problems on paraquat was brought at the first time. In connection with this, the residue of several herbicides on soil in tea fields in which several herbicides were used twice per year among seven years was investigated. It became clear that the residues of paraquat and diquat on soil were not decrease after stopped application of herbicides. Since accumulation of paraquat to soil was anxious, the influence of paraquat to the growth of some crops, turnip, carrot and so on, was experimented with used two type soils, alluival soil and volcanic ash soil, to which paraquat was added with high concentration. The influence of paraquat was more clearly in volcanic ash soil for weak soil adsorption of paraquat. On the crops in volcanic ash soil over 100ppm soil concentration of paraquat, chlorosis was appeared and the yield was decreased clearly. It became clearly by the investigation into the actual condition that the residues of paraquat in fields were related with used amount in fields.
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  • Norio SHIRAKAWA, Hiromi TOMIOKA, Masaki TAKEUCHI, Tadashi ICHIKAWA
    1990 Volume 15 Issue 2 Pages 283-294
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    Inabenfide is a new plant growth regulator discovered and developed by Chugai Pharmaceutical Co. Ltd. The biggest change in rice culture in recent years in Japan has been the remarkable development in mechanization of rice-transplanting and rice harvesting. Thus, attention is being paid to development of seedling tough to withstanding mechanized transplantation and of culture techniques for preventing lodging of rice plants before harvesting. For these reasons, it has long been desired to establish good cultivation techniques or to develop plant growth regulation with the use of chemicals so that sufficiently tough seedlings and plants having good properties for mechanized harvesting can be realized. We have searched for several years to find compounds capable of regulating the growth of rice plants, and found that isonicotinanilide represented by the formula, 4′-chloro-2′-(α-hydroxybenzyl) isonicotinanilide (inabenfide, Seritard®), has excellent growth regulating activity. The treatment of inabenfide in nursery boxes strongly controlled growth of rice seedling after treatments with 0.01 to 1g per box, and resulted in good seedlings. When inabenfide was treated on rice paddies at a rate of 2.4kg per ha on either the 62nd, 52nd, 42nd, 32nd, 22nd and 12th day before heading, the resultant growth showed shorter plants and less tendency to lodge. As a result, the yield also increased, as did the number of panicles, percentage of well ripening, and 1000-Kernel weight. On the other hand, a large number of official trials carried out in Japan since 1981 have demonstrated the effective qualities of inabenfide. It is now registered for agriculture use in Japan and under developing in some countries in Southeast Asia. The action sites of inabenfide is the inhibition of oxidation of ent-Kaurene, ent-Kaurenol and ent-Kaurenal in GA biosynthesis. Inabenfide has several favourable properties: It is low in acute mammalia toxicity and fish toxicity, causes no skin and eye irritation, has no impact on usefull insects and no phytotoxicity.
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  • Shionogi & Co., Ltd.
    1990 Volume 15 Issue 2 Pages 297-304
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    In order to investigate the toxicological properties of MITC and its formulations, a number of animal toxicity studies were conducted. In conclusion MITC is a toxic substance and shows severe corrosive effects and inflammation to skin and mucous membranes. In addition, it's vapours irritate mucous membranes and are lachrymatory.
    In a sensitization test in guinea pig, the test substance showed a mild skin sensitizing potential. In sub-chronic studies administered by oral gavage to rats and mice, MITC gave considerable dose-related toxic effects (e. g. stomach lesions, small round cell infiltration of the liver, slight spermatogenic disorder, decreased body weight gain, decreased ovary weight in mice, etc.) particularly at higher doses. A repeat study on mice to assess the effect on ovaries did not give any treatmentrelated effects in these organs. Long term chronic oral toxicity/oncogenicity studies in which MITC was administered to rats or mice in the drinking water, did not show any of the dose-dependent or substance-related effects that had been found in the sub-chronic studies. The only significant changes in the long term studies were a decreased body weight gain and water consumption in the high dose groups.
    MITC showed no oncogenic activity and had no adverse effect on reproductive capacity or in teratogenicity studies. In a number of mutagenicity studies, Rec-assay, reverse mutation, mouse micronucleus test, unscheduled DNA synthesis, sister chromatid exchange and forward mutation, MITC was negative although a in vitro chromosome aberration in Chinese hamster's cells was positive. Whilst in human lymphocytes it was negative. Di-Trapex and Trapexide were initially registered as soil fumigants in 1976 and 1982, respectively.
    Withholding values for registration have been set at 0.05ppm on fruits, 0.2ppm on vegetables and tea, and 0.5ppm on potatoes. MITC is a toxic substance with severe irritant effects on skin and mucous membranes, therefore, proper application in accordance with the recommended handling precautions including the use of full protective clothing must be followed. Then products containing MITC may not only be useful but also safe to users and applicators.
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  • Ishihara Sangyo Kaisha, Ltd.
    1990 Volume 15 Issue 2 Pages 305-310
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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    A wide variety of toxicological studies on fluazifop-butyl have been conducted to assess its safety. The results of these studies support the view that this herbicide will be safe it used following the recommended use instruction.
    Onecide ®EC herbicide containing fluazifopbutyl as its a. i., was registered to JMAFF at October 1986, the “Standard for withholding registration” were established with 0.1ppm for peas, potatoes, sugar beet and fruits, 0.2ppm for vegetables.
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  • [in Japanese]
    1990 Volume 15 Issue 2 Pages 311-314
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • [in Japanese]
    1990 Volume 15 Issue 2 Pages 315-318
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • [in Japanese]
    1990 Volume 15 Issue 2 Pages 319-321
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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  • [in Japanese]
    1990 Volume 15 Issue 2 Pages 322
    Published: May 20, 1990
    Released on J-STAGE: August 05, 2010
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