The efficacy of insecticide dipping of sugarcane cuttings to prevent the voracious feeding of sugarcane wireworms on the buds of cane cuttings was tested by pot and field experiments using four kinds of organophosphorus insecticides, i.e. prothiophos, isoxathion, MPP and MEP. One-hour dipping in a 1/1, 000 water solution of each insecticide reduced bud mortality to varying degrees depending on the insecticide. Wireworm survival was not significantly affected. However, 12-hr dipping in 1/1, 000 water solution was effective in reducing bud mortality and wireworm survival for all insecticides. Isoxathion was the most effective in maintaining wireworm infestations below the tolerable threshold of 5-10% bud infestation. The dipping method seems to be more effective in preventing wireworm infestations and requires lower doses of insecticides than the present control method, which consists of the application of 5%G ethylthiometon in the planting furrows at a rate of 6-9kg/10a. Use of the dipping method should reduce the rate of insecticide accumulation in soil.

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Effects of temperature on female calling, male sex pheromone response, and mating time of the smaller tea tortrix moth, Adoxophyes sp., were investigated. Mating occurred within a wide range of temperatures from 12 to 30°C, but the optimum mating temperature ranged from 15 to 25°C. The mating time occurred earlier when the ambient temperature decreased. The time of female calling and male response to the female sex pheromone occurred earlier when the temperature decreased and the weather was cool. In contrast, the onset of sexual behavior was delayed when the temperature increased and the weather was warm. The relationship between the temperature and onset of sexual behavior under the laboratory conditions accounted well for the seasonal mating time of this species in the field. Seasonal timing of the mating behavior seemed to be determined mostly by the ambient temperature under natural conditions.

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Damage to soybean caused by doves and pigeons was estimated to affect approximately 5% of cultivated acreage in Hokkaido from 1975 to 1977. There was a negative correlation between the acreage cultivated to soybean and the percentage of plants damaged (r=-0.256^*, n=91). This damage was mainly caused by Rufous Turtle Dove. The main food of Rufous Turtle Dove and Feral Pigeon consisted of vegetables whose fragments were detected in all the gullets and gizzards examined. Crops on which Rufous Turtle Dove fed included soybean (24.1%), adzuki bean (23.1%), corn (9.4%), rice (8.9%), buckwheat (7.1%), wheat (5.3%) and oat (0.5%) and accounted for 78.4% of the bird's food in fresh weight. Crop fragments accounted for 79.8% of the gullet and gizzard contents of Feral Pigeon and consisted of adzuki bean (38.7%), soybean (29.4%), rice (7.2%), wheat (5.8%), corn (1.3%) and oat (0.1%) fragments, respectively. Of these crops, wheat is likely to become a more important source of food for Rufous Turtle Dove owing to the recent increase of acreage and availability period from July to September.

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During the rearing on an artificial diet of Ostrinia furnacalis GUENÉE collected in Morioka (Iwate Prefecture), an abnormal sex ratio was found in some rearing containers which yielded predominantly or exclusively female moths. The population collected in Daiei (Tottori Prefecture) showed a similar phenomenon, whereas, the population of Koriyama (Fukushima Prefecture) and Kuroishi (Aomori Prefecture) showed a normal sex ratio. Some of the containers of the population of Sapporo (Hokkaido) 75 per cent of the population consisted of females, although there was no evidence of an abnormal sex ratio which is mainly induced by the death of male larvae at the early stage of development. However, a high percentage of eggs failed to hatch in the Daiei population, suggesting that a few males were killed during the embryonic stage. No significant differences in the period from hatching to 50 per cent moth emergence was found between the populations with a normal and abnormal sex ratio, respectively. The pupal weight of the populations with an abnormal sex ratio was somewhat smaller than that of the normal ones.

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Seasonal trends in population density and diapause attributes in Oligonychus ununguis (JACOBI) on chestnut tree, and in density of diapause eggs of this mite on deciduous oak were studied in Sapporo, Hokkaido. The mite population on chestnut occurred from late May to early October and was inferred to pass four or five generations per year. The number of mites infested on chestnut showed a bimodal seasonal fluctuation, but very few predators were observed. Photoperiodic response curve of this population was the long-day type, and the critical photoperiod was between 13.5 and 14.0hr at 18°C. Diapause was induced in mid-August, and this was 10 to 20 days earlier than the timing predicted by the critical photoperiod mentioned above. The reason for this was discussed in relation to the mode of life of O. ununguis on deciduous trees. Forty-six percent of diapause eggs deposited on deciduous oak twings died during the autumn (from late August to late October), and 14.2% of the remainder died and/or disappeared during the winter (from late October to mid-April). Termination time of diapause for the population on chestnut was late April, and hatchability of diapause eggs tested in early May was 85 to 90%.

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Resistance levels to fenitrothion and diazinon, or their oxons of organophosphorus-resistant strains of the green rice leafhopper were decreased to some extent by pre-application of piperonyl butoxide, sesamex, DEF (S, S, S-tributyl phosphorotrithioate) or IBP (Kitazin P^®). Among these substances the esterase inhibitor IBP exhibited the highest synergistic effect with fenitroxon, diazinon and diazoxon in the resistant strains. Aliesterase activity toward α-, β-naphthyl acetates was several times higher in the resistant strains than in the susceptible strain. Aliesterase activity was inhibited by IBP in the order of 10^-9M. There was no clear difference in glutathione S-transferase activity among the strains tested. Degradation activity of aliesterase partially purified from the resistant strain toward fenitrothion, diazinon and their oxons was not detected. Aliesterase activity was inhibited by fenitroxon and diazoxon in the order of 10^-9-10^-10M. Then, assuming that aliesterase protects AChE as binding protein, the effect of the addition of aliesterase on AChE inhibition by diazoxon was tested in vitro. The results obtained supported this assumption. From these results and previous studies on AChE, it was concluded that fenitrothion-resistance in this leafhopper was caused by the interaction of three factors; i.e., mutant AChE, aliesterase and mixed-function oxidases whereas diazinon-resistance was caused by the interaction of two factors, i.e., aliesterase and mixed-function oxidases.

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Dipping application of sublethal concentrations of methomyl to 4th instar larvae and pupae of the diamondback moth resulted in the increase of the fecundity of the adults produced. The concentrations employed were 10, 50, 100 and 500ppm. The adult females derived from the treated pupae laid more eggs with higher rates of fertilization as compared with the untreated check, irrespective of the concentration of methomyl. However, the adult females thus treated had a shorter life than the untreated ones. These effects of methomyl enhanced the intrinsic rate of natural increase (r) or the finite rate of increase per month (λ), and it is suggested that the application of methomyl might cause a resurgence of the moth population through the stimulation of the reproductive potential.

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The sex pheromone of the summer fruit tortrix moth (Adoxophyes orana fasciata) was extracted from 22, 000 virgin females and the attractiveness of fractionated samples was tested in a field cage. The two components, (Z)-9- and (Z)-11-tetradecenyl acetate, which were reported as the sex pheromone of this insect accounted for the whole attractiveness of the crude extract and no other compounds increased the attractiveness of the two-component mixture. In field tests, the two-component mixture (1mg in a plastic capsule) was as attractive as three virgin females. Moreover, the attractiveness of the two-component mixture was not improved by the addition of (E)-11-tetradecenyl acetate and (Z)-11-hexadecenyl acetate which were detected in the female extract. (Z)-9- and (Z)-11-tetradecenols, the reported sex pheromone components of the European subspecies (Adoxophyes orana), and 10-methyldodecyl acetate and (Z)-9-dodecenyl acetate which were present in the females of the smaller tea tortrix moth (Adoxophyes sp.) had no effect on male trapping. However the addition of more than 0.3% of (E)-9-teradecenyl acetate inhibited the attractiveness of the two-component mixture.

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During the initial stage of sex pheromone isolation in the smaller tea tortrix moth (Adoxophyes sp.), a particular fraction of Florisil column chromatography was found to be attractive for female moths of this species under field conditions. The active principle of this fraction was the acetic acid used as an ingredient of the chromatographic solvent. Subsequent field screening of 23 volatile acids revealed that acrylic, methacrylic, and propanoic acids are attractive for the female moths, though their potency was about one tenth of that of 20 virgin females attractive for males. Time of female trapping with acrylic acid traps coincided with the time of female trapping by a light trap. Almost all the female caught by the acrylic acid traps carried at least one spermatophore. EAG response of female moths to acrylic acid was weaker than that of males. No appreciable amounts of acetic, propanoic, acrylic, and methacrylic acids were detected in the volatile substances collected on Porapak R from fresh tea leaves.

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The larva of the Oriental moth, Monema (Cnidocampa) flavescens WALKER constructs a very hard cocoon shaped as a sparrow egg, and usually dark brown stripes run radially from the upper and/or bottom part on the surface of the cocoon. This characteristic pattern of stripes varies with the cocoons. The present experiments were undertaken to clarify the mechanism of appearance of the stripes on the surface of the cocoon under various conditions, and the results obtained were discussed in relation to the stripes occurring naturally in cocoons. A full-grown larva spins a thin silk cocoon surrounding the body. The silk cocoon is so small, about one half of the larva length, that the larva bends its body in the dorsal side in the cocoon during the construction of the cocoon. When the construction of the silk cocoon is completed, the larva excretes white muddy substances produced in the Malpighian tubes from the anus in the cocoon. These white muddy substances are plastered inside the wall of the silk cocoon by the pressure of the ventral side of the larva. In the larva, scoli are distributed on the subdorsal and the suprospiracular lines in a row respectively, and some of the scoli located in the 2, 3, 4, 10, and 11th segments are extremely large and tend to protrude. It seems likely that the dark brown stripes appearing on the surface of the cocoon were not plastered with the white muddy substances due to obstruction by the protruding scoli, or the scraping off of the white muddy substances by the scoli during the construction of the cocoon. The chemical nature of the white muddy substances will be reported in succeeding papers.

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Conditions to introduce volatile substances into a capillary column from a Tenax-GC cartridge after heat desorption were examined. The volatile substances from a virgin female of the peach leafminer moth, Carposina niponensis, could be collected using a Tenax-GC cartridge and analyzed. Also aerial pheromone concentration of pheromone-treated spaces could be calculated.

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