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カルタップ塩酸塩 (パダン®) の土壌微生物に及ぼす影響について調査した. 畑および水田の両状態において, カルタヅプ塩酸塩10ppm (通常施用量) と100ppm処理は糸状菌, 放線菌, 好気性・嫌気性細菌数を減少させなかった. しかし, 1,000ppm処理の糸状菌と放線菌数は実験期間 (60日間) 中減少した. また, 両状態において, 好気性・嫌気性細菌数は1,000ppm処によってそれぞれ最初の3日間あるいは15日間減少したが, その後回復した. なお, 両状態の糸状菌相は10および100ppm処理によって攪乱されなかったが, 畑状態の1,000ppm処理は糸状菌の構成を変化させた. すなわち, Penicillium spp. の割合が減少し, Trichoderma spp. と Fusarium spp. の割合は増加した. 一方, 水田状態においては, 1,000ppm処理のような高濃度でも糸状菌相に変化を与えなかった.

By employing intracellular electrodes on the 6th abdominal ganglion, Cartap hydrochloride 10 −5 M caused in all experiments a block of the provoked stimulus transmission and a decrease of the cell membrane resting potential; the giant fiber conduction was not affected. In the experiments with extracellular electrodes Cartap 10 −5 M provoked a marked increase of the spontaneous activity followed by block which partially disappeared after washing. The same effects were obtained on spontaneous activity when Cartap 10 −5 M was used on the denervated 6th abdominal ganglion and in experiments conducted at 0 Ca 2+ or at 20 m M Mg 2+ . Cartap 10 −5 M did not affect the response to direct or indirect stimulation of cockroach neuromuscular preparation. These results tend to confirm that Cartap affects the postsynaptic region of the ganglionic nervous junction. The possible cause of the resting potential decrease is also discussed.

SUMMARY In trials on a commercial cucumber nursery in Kent in 1971, malathion high-volume sprays gave good control of whitefly adults and young ‘scales’. Malathion applied at ultra-low volume (‘Turbair’) or as an aerosol was less effective. Malathion dust controlled only adults. Nicotine and petroleum oil were ineffective. In laboratory and glasshouse experiments in 1972, 16 chemicals as sprays, dips, drenches, smokes or fumigants were tested against each stage of a malathion-susceptible and a malathion-resistant whitefly population cultured on French beans. Adults and larval instars of the susceptible population were well controlled by sprays (adults) and dips (larvae) of organophosphorus insecticides, DDT, bioresmethrin and pyrethrum; but only thionazin, DDT, bioresmethrin and pyre-thrum gave adequate control of the resistant population. Thionazin drenches were moderately effective against susceptible larvae but gave poor control of resistant larvae. Dichlorvos and naled fumigants and DDT/gamma-BHC smoke controlled susceptible larvae but only DDT/gamma-BHC smoke was effective against resistant larvae. Excepting dips of cartap and DDT, treatments had little effect upon eggs. Larvae became more difficult to kill as age increased; only bioresmethrin (0·02 and 0·04 per cent active ingredient) gave good control of pupae.

カルタップとDCPA製剤との混合使用の可能性について殺虫力,殺草力および水稲に対する薬害などの点から検討した。カルタップとDCPAとの混合散布処理は,DCPAと有機リン系殺虫剤とを混合散布した場合に比べて水稲に対する薬害の少ない点ですぐれており,また混合散布してもニカメイチュウに対する殺虫効果およびヒエに対する除草効果は各薬剤単用区と同等の防除効果を発揮した。このようにカルタップが有機リン系殺虫剤と異なってDCPAの水稲に対する薬害作用を増大させないのは,in vitroでの実験でも判明したようにカルタップが水稲のDCPA分解酵素活性を全く阻害しないためと考えられる。

Fifteen insecticides were tested for their efficacy against one susceptible (S) and two field (Peng-hu and Ban-chau) strains of Plutella xylostella (L.). The synthetic pyrethroids (permethrin, cypermethrin, decamethrin, and fenvalerate) had the highest inherent toxicity to the S strain, and the organophosphorus compounds were one to two orders less effective, except Tokuthion® (O-2,4-dichlorophenyl-O-ethyl, S-propylphosphorodithioate), which was almost as toxic as the four synthetic pyrethroids. DDT, cartap, and methomyl were intermediately toxic, whereas carbaryl and propoxur were the least effective. The Peng-hu strain was only slightly resistant, whereas high levels of resistance to all compounds tested were observed in the Ban-chau strain. Nevertheless, the four synthetic pyrethroids remained the most potent, followed by Tokuthion,® cartap, and dichlorvos, to this highly multiresistant population of the diamondback moth.

Toxicity of 4 insecticides to the rice leaf roller larvae was evaluated by applying the leaf dipping method, and changes in the concentration of these insecticides in rice plants treated by the bell-jar dusting method were determined. LC 50 values for chlorpyrifos-methyl, dimethylvinphos, tetrachlorvinphos and cartap in 1st instar larvae were 0.38, 2.0, 6.2 and 0.60 ppm, and those in 5th instar larvae were 5.5, 12.5, 19. 8 and 4.1 ppm, respectively. Initial concentrations of chlorpyrifosmethyl, dimethylvinphos, tetrachlorvin-phos and cartap in the leaf blade were 14, 29, 39 and 2.6 ppm, respectively. Concentration of chlorpyrifosmethyl in the leaf blade showed the most rapid decrease whereas that of cartap showed the slowest decrease. Persistence of LC 50 levels in the leaf blade of 1st and 5th instar larvae was 1.6 and 0.4 days for chlorpyrifosmethyl, 2.3 and 0.8 days for dimethylvinphos, 2.1 and 0.8 days for tetrachlorvinphos, 5.4 and 0 day for cartap. From these results, timing for the control of the rice leaf roller was estimated to be 9-12 days after the peak of adult occurrence for chlorpyrifosmethyl, dimethylvinphos and tetrachlorvinphos, and 6 days after the peak of adult occurrence for cartap.

In vitro evaluations indicated that the conidial germination and hyphal growth of Beauveria bassiana were strongly inhibited by the insecticides carbaryl and cyhexatin, and also the fungicides chlorothalonil and zineb. Acephate, methomyl, cartap, and copper hydroxide were least toxic to this fungus.

The selection of best solvent for extracting cartap from human blood was examined. The experimental procedures were as follows ; One ml of blood sample was added to 0.5 ml of 8% sodium hydroxide solution in a 15 ml test tube. The sample was extracted with 5 ml of cyclohexane by shaking for 3 min, and centrifuged at 3000 rpm for 2 min. The cartap extracted with cyclohexane was derivatized by reacting with 3, 4-dimethyl benzyl chloride. The 3, 4-dimethyl benzyl derivative of cartap was spectrophotometrically measured by using tropaeoline OO as an ion-associating reagent. For the extraction of cartap from blood sample no interference could be observed with the compounds, such as Fe (III), Cu (II), glycine, L-phenylalanine, urea, glucose, lactose.

There are several statistical methods used in biology (entomology) for computing the effectiveness of an insecticide, based on relating the number of dead insects in the treated plat to the number of live ones in the untreated plat. In order to make experimental studies comparable and statistically meaningful, the article recommends the following formula: per cent control = 100(X - Y)/X, where X = % living in the untreated check sample and Y = % living in the treated sample. Calculation using this method eliminates errors due to deaths in the control sample which were not due to the insecticide. An example based on treatments of San Jose scale includes computation of probable errors for X and Y, and the significance of the difference between the two counts. Common biometric convention holds that when the difference between the results of two experiments is greater than three times its probable error, the results are significant and due to the treatment applied.