The fate of alloxydim-sodium (ADS), sodium salt of 2-(l-allyloxyaminobutylidene)-5, 5-dimethyl-4-methoxycarbonylcyclohexane-1, 3-dione, in soybean plants was studied using ¹⁴C-compound labeled at C-7 position. The ¹⁴C-ADS was applied on the first trifoliate at the first trifoliate stage of the plant. Total recovery of the radioactivity decreased rapidly to 50.7% of the initial radioactivity 14 days and then slowly to 35.7% 63 days after treatment. The radioactivity penetrated slowly into the leaves and reached the maximum 27.7% of the applied one 28 days after treatment. The majority of the radioactivity was found in the treated leaves and only 3.8% of the applied radioactivity was translocated to the other parts of the plant.
ADS degraded mainly to a deallyloxylated compound (CM-I) in the leaves. The amount of CM-I reached 45.6% of applied radioactivity 4 days and decreased to 12.4% 63 days after treatment. As minor metabolites, two oxazoles (CM-II and CM-III) and a demethoxycarbonylated compound (CM-VII) were found within a week to an extent of 0.5% of the applied radioactivity, respectively. When the water soluble ¹⁴C-compounds were treated with pectinase or cellulase, parent compound, CM-I, II and III were found in small amounts. Acid or alkaline hydrolyses of polar metabolites gave several unknowns.

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Isoprothiolane (diisopropyl 1, 3-dithiolan-2-ylidenemalonate) remarkably inhibited the incorporation of ¹⁴C-acetate into fatty acids and triglycerides of mycelia of Pyricularia oryzae at a concentration of 50μg/ml, but hardly inhibited the synthesis of sterols at the same concentration. Incorporation of methionine-(methyl-¹⁴C) into phospholipids was also remarkably inhibited by 50μg/ml of isorpothiolane and the accumulation of S-adenosyl methionine was observed in treated mycelia. In a cell free system, isoprothiolane did not affect fatty acid synthetase prepared from P. oryzae at a concentration of 50μg/ml.

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Alloxydim-sodium, a newly developed herbicide, was administered orally and repeatedly to rats. Within two days after dosing of the ¹⁴C-labeled compound (70mg/kg/day) for 7 days, the male rats excreted 75% of the dosed radioactivity into urine and 25% into feces, while the female ones excreted 84% and 16%, respectively. Relatively high concentrations of the radioactivity were found in the liver, kidney and blood among 24 tissues at one day after final dosing and their concentrations in ppm equivalent to the parent compound were about 20, 11 and 31, respectively. The disappearances of the radioactivity from most tissues were rapid. The disappearance from blood was slowest among them and about 10ppm remained in blood at 21 days after final dosing.
From another experiment, it was revealed that a major part of the radioactivity in feces was excreted after repeated enterohepatic circualtion.
Whole body autoradiograms were obtained from rats dosed singly ¹⁴C-alloxydim-sodium. The most wide-spread distribution of the radioactivity was observed at 6 hours after dosing. The radioactivity was slightly found in one day's sample, especially in blood and liver, and scarcely in four day's one.

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The chronic toxicity of bis (2-chloro-1-methylethyl) ether (dichlorodiisopropyl ether: DCIP), a nematicide, was studied in specific pathogen-free (SPF) mice of the ICR strain. DCIP (purity: 98.5%) was fed to each groups of 56 male and 56 female mice for a period of 104 weeks at dietary dose levels of 0, 80, 400, 2, 000 or 10, 000ppm. Seven animals of each group at 13, 26 and 52 weeks, 6 animals at 78 weeks and all surviving mice at the end of the experiment were sacrificed to carry out hematological, biochemical and pathological examinations.
In both sexes of the 10, 000ppm group, a remarkable depression of body weight gain was noted corresponding with the decrease in food consumption. Mild anemia and hemosiderin deposition and increased extramedullary hematopoiesis of the spleen were observed at 13, 26 and 52 weeks. Only female mice in the 2, 000ppm group showed a slight inhibition of body weight increase and an anemic tendency. No conspicuous changes attributable to the feeding of DCIP were observed less than in the 2, 000ppm group males and the 400ppm group females. There was also no significant increase in the incidence of age-related lesions and tumors in any treated groups as compared with those in the control group.
Based on these results, it was concluded that the maximum no-effect levels of DCIP were 2, 000ppm for male mice (198mg/kg/day) and 400ppm for female mice (35.8mg/kg/day).

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The pattern of increase or decrease of dicofol-resistance in the citrus red mite, Panonychus citri (McG.), was different from those obtained with other acaricides. It was often observed under field conditions that dicofol-resistance of P. citri increased gradually by selection with dicofol, but decreased relatively quickly by relaxation of the selection. To analyze such a pattern, the changes of susceptibility of mite populations to dicofol and the genetic basis of resistance were studied.
Natural populations of mite were collected from Tanushimaru, Fukuoka-ken, in August, 1969, and from Yoshii, Fukuoka-ken, in August, 1971, respectively. The initial population was divided into two populations, one population was selected with dicofol and another population was reared without selection. Mites were reared on young citrus trees at 25°C for 2.5-3 years. The dicofol susceptibility of eggs in the selected populations decreased considerably, but its decreasing pattern was complicated. On the other hand, the susceptibility of eggs in the unselected populations increased remarkably after 13 or 23 months (about 33 or 58 generations).
Dicofol-resistant strain selected from Yoshii population, and a susceptible strain of Ogi population collected from Saga-ken, were crossed. The susceptibilities of F₁ and B₁ adult females were compared with each other by using log concentration-probit mortality lines and curve. No remarkable differences were found between both susceptibilities of reciprocal crosses, but these susceptibilities of hybrid adult females were fairly higher than the average level of both resistant and susceptible parental strains. Thus, it was suggested that dicofol-resistance would be manifested as a recessive character. In the results of backcross series, the observed log concentration-probit mortality curve fitted well with the expected one, based on a hypothesis that one major gene was responsible for the resistance to dicofol.

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A new screening system to select anti-mildew substances using barley seedling was devised. To begin with, anti-mildew substances exhibiting translocating property were selected by means of brush inoculation method; a leaf of the seedling the root of which was wrapped in an absorbent cotton containing a test solution was inoculated with conidia of Erysiphe graminis from barley plant using a small brush. Preventive and, or curative activities was examined as the second screening; conidia of E. graminis were dispersed from inocula plants to the test plants by the artificial wind in a cabinet equipped with an electric fan. Finally, anti-mildew substance effective against the disease of cucumber was selected in a green house as the third screening. From among 1, 680 strains of Actinomycetes, only one strain (B-98891) was selected through the screening system. The brush inoculation method was successfully applied to detect anti-mildew activity through the isolation and the purification process of mildiomycin.

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Mildiomycin (MIL) was effective by foliar application against eight genera of powdery mildew fungi on fifteen kinds of plants. Its effect at 80ppm was equal to that of quinomethionate on cucumber, and surpassed quinomethionate and the other fungicides on almost every other plants tested. MIL was also effective against benomyl-resistant strain of Sphaerotheca fuliginea, causative fungus of cucumber powdery mildew. Phytotoxicity was not observed on any plants tested.
The systemic property of MIL was shown under the soil-free condition by rootsoaking. Translaminar activity of MIL, which was proved on tobacco leaves seemed to explain its good control effect against Leveillula taurica, an endoparasitic fungus causing powdery mildew of green pepper.

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Pentachlorothioanisole (PCTA), a metabolite of pentachloronitrobenzene (PCNB), was converted to methyl pentachlorophenyl sulfoxide (PCTA-SO) and methyl pentachlorophenyl sulfone (PCTA-SO₂) in soil under laboratory conditions. The conversion was hardly observed in autoclaved soil, suggesting participation of microorganisms in the process. The presence of PCTA-SO and PCTA-SO₂ was also confirmed in soil from a field plot treated with PCNB and in peanuts harvested from the plot. A trace amount of PCTA-SO was also detected in young corn plants grown in a culture solution containing PCNB.

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The ¹⁴C-labeled organophosphorus insecticide, propaphos [dipropyl 4-(methylthio) phenyl phosphate], degraded rapidly when exposed to sunlight as deposits on silica gel plates, glass surface, or in water solution. The half-life of the chemical was less than 2 hours in each case. Degradation pathways included oxidation of the methylthio sulfur to sulfoxide and sulfone derivatives, hydrolysis of the phosphorous-O-phenyl ester, and undefined transformations leading to highly polar products that increased in quantity with time of exposure. Exposure of water solution of the chemical to artificial UV light resulted in very rapid degradation to the same major photoproducts as were generated by exposure to sunlight and in liberation of ¹⁴C-carbon dioxide.

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Integumentary cuticle formation under culture conditions was examined using tissue fragments prepared from the diapausing larvae of the rice stem borer, Chilo suppressalis Walker. Exposure of the tissue to Grace's medium containing 1μg/ml β-ecdysone for 24hr was the optimum hormonal treatment for new cuticle formation. The new cuticle was 5.4±1.2μm three days after the onset of cultivation. The median effective concentration of β-ecdysone in Grace's medium was 0.13±0.02μg/ml for new cuticle formation. The thickness of the cuticle formed in the medium containing the chitin synthesis inhibitors polyoxin D and PH 60-38 decreased as the concentration of the inhibitors increased. The median effective concentration for inhibition of cuticle formation was 9.77×10^-6M for polyoxin D and 5.62×10^-7M for PH 60-38. The response of the cultured integument to polyoxin D and PH 60-38 was rapid and irreversible. The cultured integument of C. suppressalis has various advantages as a bioassay system; simplicity of manipulation, reproducibility, and quantification of the biological response.

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The residue levels of apparent alloxydim-sodium (ADS), sodium salt of 2-(1-allyloxyaminobutylidene)-5, 5-dimethyl-4-methoxycarbonylcyclohexane-1, 3-dione, in soybean seeds were studied using ¹⁴C-ADS compounds labeled at either C-7 or C-1, 5 position. The ¹⁴C-ADS was applied on the first trifoliate at the second trifoliate stage of the plant. One group of the treated plants was kept under the condition preventing from rainfall. Another group was showered artificially 3 or 7 days after treatment of ¹⁴C-ADS and then kept outdoors for 9 or 10 weeks.
The residue levels equivalent to alloxydim-sodium in the seeds were 0.022-0.039ppm at 9 weeks and 0.024-0.050ppm at 10 weeks for all samples. So neither the difference in the condition such as artificial rain nor the difference in the position of ¹⁴C-label affected the residue levels in the seeds. About 10% of the radioactivity in seeds harvested 9 weeks after treatment was found in lipid fraction. Most of the radioactivity was detected in the water soluble fraction after precipitating protein fraction, in which about 28% and 5% of the radioactivity were found in case of 7-¹⁴C and 1, 5-¹⁴C, respectively. Thus the dimedone moiety of ADS was only a little incorporated into proteins.

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[in Japanese]

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A mode of herbicidal activity of methoxyphenone including selectivity and chlorosis induction was studied. For the elucidation of selective herbicidal action between rice plant (tolerant) and barnyardgrass (susceptible), differences in absorption, translocation and metabolism of methoxyphenone applied to the leaves, roots and seeds of the two plants were compared with the value of selective index estimated from chlorosis induction. The diffrences in absorption and translocation of methoxyphenone from the roots and seeds are evidently the dominant factors to cause the selective effect on both plants.
No inhibitory effect of methoxyphenone on Hill reaction was observed. Slight inhibition was observed in respiration and RNA synthesis, but protein synthesis was not inhibited at all.
Methoxyphenone inhibited the accumulation of chlorophyll and carotenoid in barnyard millet seedlings under strong light to yield white seedlings. Chlorophyll was accumulated in the treated seedlings grown under weak light but was destroyed in seedlings exposed to strong light. Carotenoid synthesis was inhibited in darkness as well as in the light and caused the accumulation of carotenoid precursors, phytofluene and ζ-carotene. Seedlings exposed to strong light lacked normal chloroplast structure. The disruption of the chloroplasts and loss of chlorophyll was supposed to be due to the absence of carotenoids in the treated plants, which would normally act to protect the chloroplasts and chlorophylls from photodestruction.

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The green rice leafhoppers, Nephotettix cincticeps Uhler, have developed cross-resistance to many N-methylcarbamate insecticides due to the reduced sensitivity of its acetylcholinesterase (AChE) to the carbamates.
We tried to develope new carbamates which could control such resistant leafhopper, and made various structural modifications which would increase the interaction with such altered AChE. Aryl N-propylcarbamates were found to be potent inhibitors of the resistant AChE, but not potent insecticides.
Combination of the N-propylcarbamate with N-methylcarbamate with same or different phenyl group gave a potent synergistic insecticidal activity, and were shown to be promising insecticides for practical application.
The mechanism was elusidated on biochemical basis. The AChE from resistant leafhopper has the additional site which is sensitive to N-propyl but insensitive to N-methylcarbamates other than the N-methylcarbamate-sensitive site present in AChE from susceptible leafhopper. Single inhibitor could not inhibit both sites, but combining two inhibitors, each interacts with the preferred site. Recognition of such mechanism would provide the chance for finding another chemicals and a rational basis for the use of combined anti-AChEs.

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