The amounts of piperophos adsorbed on various type of soils, clay minerals and organic substances were estimated. Soils containing montmorillonite adsorbed larger amount of piperophos than those containing kaolinite, mica and allophane. The order of adsorption was humic acids>montmorillonite>halloysite>kaolinite>allophane. Peatmoss, lignin and compost also adsorbed a large amount of piperophos. Both clay minerals and organic matter were effective adsorbents for piperophos and the properties of these colloids influenced adsorption of the herbicide. The removal of organic matter of soils by hydrogen peroxide oxidation decreased the adsorption in the soils containing kaolinite, mica and allophane, but increased that in soils containing montmorillonite. In the case of soils containing low adsorptive clay minerals (kaolinite, allophane), the amount of piperophos adsorbed was highly correlated with clay and total carbon contents on a multiple regression equation. However, there were no correlations for soils containing highly adsorptive clay mineral (montmorillonite).

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Several compounds which belong to the alkylbenzenesulfonates, alkyl sulfates and alkanesulfonates were tested for their antiviral activities. Alkylbenzenesulfonates were more effective against the disease development caused by CMV (cucumber mosaic virus) and CGMMV (cucumber green mottle mosaic virus) than that of TMV (tobacco mosaic virus). Among the test compounds, calcium octylbenzenesulfonate was the most effective on CMV. Calcium decylbenzenesulfonate proved most effective on CGMMV. Among the alkyl sulfates, sodium decyl sulfate was specifically effective on the disease development caused by CGMMV. The antiviral activities of the alkanesulfonates on TMV, CMV and CGMMV were low in general, when compared with those of other groups of the test compounds. Some metal salts of branched dodecylbenzenesulfonate were also examined for their antiviral activities on the three viruses mentioned.

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Leaching and metabolism of fluoroimide, N-(4-fluorophenyl)-2, 3-dichloromaleimide, in soils were investigated using two ¹⁴C compounds labeled at either the benzene ring or carbonyl groups. The distance of fluoroimide moved from the soil surface was only a few cm in each of three soil columns even after elution with water corresponding to 200mm rainfall; but its hydrolyzed compounds, which were easily formed in the soil columns, were leached out from the 20cm column of two soils with low organic carbon content. The mobilities of fluoroimide and its hydrolyzed compounds in the soils were similar to those of DDT and 2, 4-D, respectively. Fluoroimide contents in soils decreased rapidly to 50% within 1 day and 95% disappeared in 2 days through hydrolysis of its CO-N bond and then degradation. The main metabolites of fluoroimide were 4-fluorodichloromaleanilic acid and its sodium salt which have been recognized to be the plant metabolites. These metabolites were further hydrolyzed to 2, 3-dichloromaleic acid and 4-fluorroaniline. The former was then degraded rapidly by releasing CO₂ from its carbonyl groups, while the latter was bound to soil particles and could not be extracted by the solvent used. The latter was, however, considered to be degraded through benzene ring fission by soil microorganisms under aerobic upland conditions. Stepwise reductive metabolism as reported in DDT was also observed on the dichloroethylene moiety of fluoroimide.

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The degradation of ¹⁴C-naproanilide [1-(2-naphthoxy) propionanilide] labelled at the naphthalene-ring in three different soils under oxidative (aerobic) and reductive (anaerobic) flooded conditions was studied in the laboratory. ¹⁴C-Naproanilide was rapidly degraded under both conditions, and the difference in rates among the different soils was small. The degradation products in the organic solvent extracts detected by thin layer chromatography were composed of 1-(2-naphthoxy) propionic acid, the major product, and methyl 1-(2-naphthoxy) propionate, 2-naphthol, 2-hydroxy-1, 4-naphthoquinone and 2, 3-, 2, 6- and 2, 7-dihydroxynaphthalenes, minor products. A larger amount of ¹⁴CO₂ was liberated under oxidative than reductive conditions. Soil-bound residues of the radioactive materials in the two mineral soils increased to a larger extent under oxidative than reductive conditions, but the increase under both conditions was small in volcanic ash soil.

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To investigate the action mechanism of sulfonate anionic surfactant against plant viral infection, inhibitory action of sodium and calcium salts of branched dodecylbenzenesulfonic acid (abbreviated as DBS-Na for the former, DBS-Ca for the latter and DBS for both) to tabacco mosaic virus (TMV) ordinary strain was studied using the French bean local lesion assay method. DBS-Ca inhibited the local lesion formation by 90% or more at 1, 000ppm when added in TMV inoculum, at 2, 000ppm when applied after TMV inoculation and at 2, 500ppm when applied prior to inoculation of TMV. The inhibitory effect of DBS-Na was somewhat less than that of DBS-Ca. When DBS-Ca was added in TMV inoculum, the inhibition of local lesion formation was primarily dependent upon the concentration of DBS-Ca itself, and little upon the concentration proportion of DBS-Ca to TMV or the incubation period in which they were mixed. DBS-Ca at 2, 000ppm, when applied within ca. 4hr after TMV inoculation, almost completely inhibited local lesion formation. Experiments by ultracentrifugation, Schlieren pattern measurement and gel filtration indicated that disintegration of TMV by DBS or absorption or reaction between them was little involved in the inhibitory effect. Also, the inhibitory effect of DBS-Ca incorporated through the petiol of French bean from aqueous solution was estimated, and the inhibition was remarkable at 200ppm or more of DBS-Ca in the solution. The results described above suggest that the inhibitory action of DBS to TMV infection is not due to the disintegration or inactivation of TMV but due to the depression of viral replication resulting from the disturbance in metabolism of host cell and in the function of the membrane at an early stage of TMV infec tion in that cell.

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Effects of a spray with techlofthalam [N-(2, 3-dichlorophenyl)-3, 4, 5, 6-tetrachlorophthalamic acid] at 100ppm on the population and aggressiveness of Xanthomonas oryzae, the causal organism of bacterial leaf blight of the rice plant, in rice leaf tissues were periodically studied. Change of bacterial populations after spraying showed a definite trend independent of application time, 1 day before and 3 days after hydathode inoculation, and after lesion formation. The bacterial population relatively decreased a few days after spraying and then it remained consistent at a much lower level, particularly at approximately 10% the level of unsprayed plants in case of spraying following lesion formation. Bacteria isolated from leaves 17 and 30 days after spraying produced smaller lesions on rice leaves free of techlofthalam than those from unsprayed leaves. This indicates the lower aggressiveness of the bacteria in sprayed leaves and retention of the property even after isolation from the host. The bacteria, however, recovered their original aggressiveness when grown on an agar medium or in rice leaves.

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Five N-substituted 2-hydroxymethyl-3, 4, 5, 6-tetrachlorobenzamide derivatives were prepared by reduction of corresponding phthalimide derivatives with sodium borohydride. They were tested for their potential activity to control several plant diseases. No control activity was manifested on bacterial leaf blight of rice, but some showed high activity against rice blast and cucumber anthracnose.

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Methods of extraction and analysis suited for analysis of aged, unknown residues on wheat, barley, oats, sorghum, rice in husk, milled rice, polished rice and cooked rice are reported for carbaryl, for the pyrethroids bioresmethrin, fenothrin, d-fenothrin and pyrethrum I, and for the organophosphorus insecticides dichlorvos, fenithrothion, methacrifos and pirimiphos-methyl. Fortification studies were performed for each insecticide on each commodity; six regimes were used to extract insecticides that had been applied to grains 3-6 months previously in order to obtain adequate methods of extraction. Amounts of aged residues of dichlorvos, fenitrothion, methacrifos and pirimiphos-methyl, after standing whole grain in methanol or ethanol for 12 hours, were over 90% of the amounts obtained after extracting for 26 or 36 hours and above the levels extracted by hexane. Recoveries of fortified samples extracted by ethanol or methanol from all commodities ranged between 89 and 100%. The organophosphorus insecticides were determined by gas-liquid chromatography (glc) using a phosphorus-specific detector. Residue levels of fenitrothion were also determined colorimetrically, after hydrolysis to 4-nitro-3-methylphenoxide and clean-up by the addition of barium chloride. This method was suitable for determination of residue levels greater than 2mg/kg. At least 80% of aged residues of carbaryl was extracted by standing grain in acetone or ethanol for 12 hours. Carbaryl was determined by glc, using electron capture, after derivatization to 2-chloroacetyl-1-naphthol and also semi quantitatively by thin-layer chromatography with 4-nitrobenzenediazonium fluoroborate as the chromogenic reagent. A two phase procedure using dilute alkali, 2-chloroacetic-anhydride and diethyl ether resulted in >95% acetylation of 1-naphthol, 4-cyanophenol and of the acidic phenols 2, 4, 5-trichlorophenol, 4-nitrophenol and 4-nitro-3-methylphenol provided that the pH of the aqueous phase was close to the pK_a of the phenol. Over 90% of the amounts of the pyrethroids bioremethrin, fenothrin, d-fenothrin and pyrethrum I extracted from all commodities after 26-36 hours in ethanol, light petroleum or acetone was extracted after 12 hours in light petroleum, with the exception that light petroleum was inadequate for the extraction of these pyrethroids from cooked rice. The pyrethroids, after alkaline hydrolysis, were determined colorimetrically from the reaction of chrysanthemic acid with acidified mercury (II) sulphate. Recoveries of fortified samples were between 89 and 95%.

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Loss of bioresmethrin, carbaryl and d-fenothrin from post-harvest application to wheat was related quantitatively to wheat temperature and equilibrium relative humidity. Coapplication with piperonyl butoxide increased the stability of bioresmethrin, but had little, if any, effect on the persistence of Carbaryl. Results for d-fenothrin were inconclusive.

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Levels of residues of bioresmethrin, Carbaryl, fenitrothion, d-fenothrin, methacrifos and pirimiphos-methyl were determined on unhusked rice, husked rice, polished rice and barley over a storage period of six months. The observed levels were close to levels predicted from use of a model which relates rate of loss of residue levels to a rate constant and only two variables, temperature and equilibrium relative humidity. The fate of residues was determined during processing of rice and barley. Data on losses during processing are also given for dichlorvos on rice and malathion on barley. After the milling process, residues of all protectants applied to unhusked rice were concentrated in the husks and bran. The proportion of protectant lost during cooking of rice varied between protectants, and was especially great for dichlorvos, methacrifos and carbaryl. All protectants were extensively degraded during commercial malting of barley and the loss of methacrifos was especially pronounced.

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The herbicidal action of alloxydim-sodium (ADS), sodium salt of 2-(1-allyloxyaminobutylidene)-5, 5-dimethyl-4-methoxycarbonylcyclohexane-1, 3-dione, on oat (Avena sativa) was investigated in post-emergence treatment. ADS applied to the foliage arrested the elongation of new leaves within two days and necrosis occurred in the meristematic region of the shoot within three days after treatment. At this time all leaves remained healthy in appearance. Subsequently, necrosis expanded to the base of the stem and finally to the entire plant. Histological investigations of the meristematic region of the shoots showed that the cell arrangement was abnormal, and nuclei appeared to be aggregated 12 hours after the treatment in the treated plants. These results suggested that ADS applied to the foliage primarily affected the apical meristems of shoots and disturbed the normal function in the meristems.

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The adsorption constant (K) of fungicidal dialkyl 1, 3-dithiolan-2-ylidenemalonates and related compounds with a soil sample from Osaka district was determined at 25°C. The value of K increases regularly with increasing chain length of the alkyl groups. The log K value was nicely correlated with the hydrophobic parameter, log P, where P is the partition coefficient determined with the 1-octanol-water system. The adsorption process of these compounds seems to be governed by the hydrophobic interaction with the soil components. The mobility of these compounds in the soil with water was also determined using soil-column chromatography. The log (mobility constant) value was linearly related to log K with a negative slope. The stronger the soil adsorption is, the slower is the movement in the soil layer.

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The binding of ¹⁴C-procymidone to a sensitive fungus, Botrytis cinerea, was examined. Procymidone rapidly bound to the hyphal cell and the binding almost equilibrated within 1min. The binding was dependent on the external concentration of procymidone and cell density, but not on the temperature and metabolic activity of the cells. The binding process was reversible and more than 95% of the bound procymidone was removed from the cells through washing. Hyphal growth, which was entirely halted by the incubation with procymidone, also recovered after washing. These results indicate that procymidone displays toxic activity to reversibly bind itself to the hyphal cells; its binding and release are very rapid processes.

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A combination of photochemical and reductive dechlorination techniques is used to prepare analogues of dieldrin, endosulfan (α- and β-series) and isobenzan in which the chlorine atoms at C₁ and C₄ (bridge-end) of the 1, 2, 3, 4, 7, 7-hexachlorobicyclo[2.2.1.]hept-2-ene system are retained whilst those at C₂, C₃ (ethylenic) and C₇ (methano-bridge) are variously replaced by hydrogen atoms. The identification of chlorine substitution patterns by nmr is discussed in relation to available information on known compounds. This is part of an investigation to determine whether there is any consistent relationship between different groups of cyclodiene insecticides in regard to the effect of reductive dechlorination on their toxicities to insects.

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Residue analysis of alloxydim-sodium[sodium salt of 2-(1-allyloxyaminobutylidene)-5, 5-dimethyl-4-methoxycarbonyl cyclohexane-1, 3-dione) and its degraded compounds in crops and soils were investigated. As a result of the experiments by three different analytical methods, high performance liquid chromatography (HPLC), gas chromatography (GC) and ultra-violet spectrophotometry (UV), the HPLC method was found to be most suitable. Alloxydim and degraded compounds in samples were extracted with methanol. These compounds in an aqueous methanol solution were extracted separately with n-hexane and methylene chloride. Alloxydim in n-hexane was cleaned up by liquid-liquid separation. Degraded compounds in methylene chloride were subjected to thin layer chromatography. Each compound was determined by the HPLC method. The lower limit of detection for each compound was 0.01ppm. Recoveries of alloxydim were 86-93% in crops and 85-91% in soils, and those of degraded compounds were 75-92% in crops and 87-92% in soils.

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Aquatic organisms were kept in an aquarium tank containing 1 ppb of chlorophenyl-(U)-¹⁴C-DDT, 1, 2, 3, 4, 10-¹⁴C-aldrin, 2, 4-dichlorophenyl-(U)-¹⁴C-prothiophos (O-2, 4-dichlorophenyl O-ethyl S-propylphosphorodithioate), dimethyl-¹⁴C-isothioate [S-2-(isopropylthio)-ethyldimethylphosphorothiolothionate], naphthyl-1-¹⁴C-carbaryl, and N-methyl-¹⁴C-XMC (3, 5-xylyl methylcarbamate), respectively, and uptake of these pesticides in guppy (Lebistes reticulatus Peters), red snail (Indoplanorbis exustus Deshays), mosquito larvae (Culex pipiens pallens molestus Foriskal) and Daphnia pulex deGeer was investigated. Uptake of DDT by mosquito larvae was the most rapid among the aquatic organisms tested, and the snail accumulated the least in this experiment. Aldrin was rapidly transformed to dieldrin in guppy, but was scarcely found at all in Daphnia. The uptake of prothiophos was high in Daphnia, differing from the lower uptake by other organisms which easily degraded this chemical compound. The uptake of isothioate, carbaryl and XMC was fairly low, and those three pesticides were metabolized rapidly by all organisms. The uptake and metabolism of pesticides were remarkably influenced by difference of aquatic organism species and chemical variety. It was also found that the uptake of pesticides in the present experiment was different from that in the model ecosystem study which involved a food chain system.

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An investigation was made on the effect of the addition of a 7.8% sucrose solution to the acceptability of thallous nitrate solutions (0.09% and 0.18%) by wild Norway rats. The addition of sucrose resulted in a ten-fold increase in the acceptability of the 0.09% thallous nitrate solution. Furthermore, 100% mortality was obtained among test animals offered sucrose-sweetened 0.09% and 0.18% thallous nitrate, while only 20% mortality was obtained with unsweetened 0.09% thallous nitrate. Thus, it was suggested that sweetened thallous nitrate solutions (of appropriate concentrations) might prove to be an effective rodenticide in warehouses.

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Topical application of EDB (1, 2-dibromoethane) on silkworm larvae of up to 2, 000μg/g body weight showed no harmful effects on the larval development, cocoonation and egg-laying ability of the emerged moths. Neither oral administration of EDB by feeding mulberry leaves treated with 4, 000ppm emulsion nor rearing on leaves smeared with 1, 000ppm EDB emulsion throughout the larval period had an effect on silkworm development. Some silkworm were, however, affected by exposure to EDB vapor in an air-tight container for 1hr. Those larvae or pupae surviving after such exposure developed into moths and laid eggs normally. A normal number of the eggs hatched. Tests for mutagenic effect using the egg color mutant, pere, did not show EDB to be a mutagen.

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The characteristics of benthiocarb sulfoxide, a degradation product of benthiocarb herbicide by irradiation of light and in soil, was examined by thin layer chromatography, chemical reduction, and mass spectrometry. The compound was unstable and degraded partially on silicagel plates, giving an unidentified product which could be reconverted to benthiocarb sulfoxide on the plates. Benthiocarb sulfoxide was easily reduced to benthiocarb with zincacetic acid. The sulfoxide was also reduced to benthiocarb under exposure to the ultraviolet lamp. The mass spectrum of the sulfoxide was the same as that of benthiocarb, presumably because the sulfoxide is easily reduced to benthiocarb through the impact of an electron beam.

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Change in population of Xanthomonas oryzae and the concentration of techlofthalam in a guttation droplet on rice leaves sprayed with techlofthalam [N-(2, 3-dichlorophenyl)-3, 4, 5, 6-tetrachlorophthalamic acid] at a concentration of 100ppm were examined. Bacterial population in the guttation droplet lowered when the percent of lesion area on the leaf decreased. The concentration of techlofthalam detected was 0.1ppm or below, with the exception of one sample 1 day after spraying.

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The action of soybean lecithin on each stage of the life cycle of blast fungus (Pyricularia oryzae Cav.) was investigated by inoculation of spore suspension containing lecithin into scale tissues of onion bulb. Soybean lecithin completely inhibited the penetration of infection hyphae at a concentration of 5ppm, and sporulation was inhibited conspicuously at a concentration above 10ppm. The inhibitory effect on mycelial growth however, was very weak even at a concentration of 500ppm. While the inhibitory effect on the appressorial formation was observed at concentrations above 500ppm, and inhibition was complete at a concentration of 1, 000ppm, the inhibitory effect on conidial germination and hyphal growth was not recognized even at this latter concentration.

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Residues of methoxyphenone (NK-049) in watermelon, tomato, carrot, rice grain and rice straw were extracted with acetone and partitioned into chloroform from an aqueous solution after distillation of acetone. Chloroform was distilled and the residues were cleaned up by two steps of column chromatography. Ten gram of silica gel was used as adsorbent of the first chromatography and methoxyphenone was eluted with 100ml of benzene containing 5% of ethyl acetate after washing with 60ml of benzene. On the second chromatography, 2g of alumina containing 0.1ml of 50% silver nitrate aqueous solution was added to the column of 10g of Florisil. Methoxyphenone was eluted with 100ml of benzene containing 5% of ethyl ether after washing with 100ml of benzene. Then the residue was dissolved in 1ml of methanol and 80μl of the solution was injected into a high performance liquid chromatograph fitted with a stainless steel column (4.6mm×25cm) packed with Jasco, SC-02. The column was eluted with methanol and water (75+25) at a flow rate of 2ml/min. The detector was UVIDEC-100 and the wavelength was 295nm. The liquid chromatogram was much clearer than the gas chromatogram with ECD and no interfering peaks were observed in any samples. The lower limits of detection were 0.005ppm (watermelon, tomato, carrot, rice grain) and 0.03ppm (rice straw), so this method was as sensitive as ECD gas chromatography. The average recoveries of methoxyphenone were 88-93%.

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Some antilipidemic agents of several different chemical classes and their related compounds were synthesized, and their ovicidal activities were assayed on freshly laid eggs of the azuki bean weevil, Callosobruchus chinensis. In general, those chemicals which have been reported to possess antilipidemic activity showed moderate ovicidal activity. The antilipidemic agent clofibrate [ethyl α-(4-chlorophenoxy)-α-methylpropionate], which has been reported to have acute toxicity on the milkweed bug, showed considerably high ovicidal activity. However, none of the α-(4-chlorophenoxy)-α-methylpropionic acid amides had ovicidal activity. Ethyl 2, 2, 3-trimethyl-4-(4′-chlorophenyl)-3-butenoate showed the highest ovicidal activity among the tested compounds.

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The residue analysis of benzomate in orange and apple was investigated. Benzomate in samples was extracted with methanol and reextracted with methylene chloride. The extract was evaporated under a reduced pressure, diluted with acetonitrile and then washed with n-hexane. The acetonitrile phase was evaporated to dryness. The residue was dissolved in a small portion of methylene chloride and then streaked on a tlc plate (Merck Art. 5554). Benzomate on the plate was eluted with methanol after developing with methylene chloride. After evaporating the solvent, the residue was dissolved in 1ml of acetonitrile and then 10μl of the solution was injected into a high performance liquid chromatograph fitted with a column (φ4.6mm×25cm) packed with Zorbax C8. The column was eluted with an acetonitrile and water mixture (8:2, v/v) at a flow rate of 1ml/min. The absorbance was monitored at 254nm with a 8μl flow cell. The limit of the detection using 50g of sample was 0.04ppm and recovery was about 80%.

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