Esterase activity of the citrus red mite, Panonychus citri (MCGREGOR), on citrus and pear in different habitats was studied by thin layer electrophoresis. The esterases hydrolysing β-naphthylacetate in the citrus red mite were separated into 6 bands. E₁, E₂, E₃, E₄ and E₅ bands were detected in the mites of the non-diapausing strain, while in the diapausing strain only E₄, E₅ and E₆ bands were observed. In the mites of the non-diapausing strain, the activity of E₃ bands was high in group on citrus and low in that on pear. When the mites of the non-diapausing strain on pear were reared with citrus leaves for one generation, the activity of their E₃ band changed and became higher. It became low when the mites on citrus were reared with pear leaves for two generations.

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It is well known that the larva of the oriental moth, Monema (Cnidocampa) flavescens WALKER, constructs a very hard cocoon shaped as a sparrow-egg. The moth emerges from the hard cocoon by opening a hole at the upper part of the cocoon, and the mature larva makes preparations for the eclosion. A part of the inner wall of the cocoon corresponding to the opening's edge shows a circular area which is thinned presumably through the pressure of the scoli and setae located on the thorax of the larva. The cocoon is cracked along the circular and thinned area line by pressure at the time of eclosion.

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Although cross-infection of Spodoptera litura with the cytoplasmic-polyhedrosis virus (CPV) of Hyphantria cunea, is usually not lethal, a high mortality rate and a short period of lethal infection occur when the infected larvae are reared on food plants with low nutritive value, which delays larval growth.
Hyphantria cunea and Spodoptera litura subjected to cross-infection with the CPV of Bombyx mori recovered from the disease. In these insects, however, the susceptibility to cross-infection with the CPV of Bombyx mori and disease recovery were not always affected by feeding on different food plants and exposure of the infected larvae to stress agents such as cold (5°C), starvation and Na-EDTA administration.

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A rearing method for the production of successive generations of Anomala cuprea HOPE was tested in the laboratory. The third instar larvae were exposed to low temperatures (10 and 20°C), for four different periods of time (10, 20, 30 and 40 days). The duration of the developmental period from the egg stage to adult emergence was considerably shortened by the treatment at 20°C, and the shortest duration was observed when the larvae were exposed to 20°C for 30 days on the 30th day after the third instar. The mean number of days required for the completion of their life cycle was 181 days. These findings show that the adult was able to repeat a half-year cycle. Therefore, various artificial diets for rearing adults were studied in this experiment. The adults were reared on two artificial diets (A and B) containing dried powder of young leaves of Podocarpus macrophylla D. DON. With regard to the adult longevity, egg number and hatchability, the artificial diet A was superior to the other diets.

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A rice brown planthopper population (T population) collected in rice fields of Takamatsu City, Kagawa Prefecture in October 1979 was selected in the laboratory with carbaryl or propoxur for 12 successive generations. Compared with the initial LD₅₀ levels of the parent population (T population), the carbaryl-selected strain (Rc) developed a 4-fold resistance to carbaryl, 2 to 4-fold resistance to most of the carbamates tested and also to the organophosphorus insecticides, dimethylvinphos, tetrachlorvinphos, monocrotophos, propaphos, fenthion, pyridaphenthion, EPN, disulfoton, malathion, dimethoate, phenthoate and mecarbam while the susceptibility to diazinon, cyanofenphos and isoxathion remained unchanged. The propoxur-selected strain (Rp) acquired a 5-fold resistance to propoxur, 2- to 4-fold resistance to the other carbamates tested and 2- to 11-fold resistance to dimethylvinphos, propaphos, isoxathion, EPN, disulfoton, malathion, dimethoate, phenthoate and mecarbam while the LD₅₀ for monocrotophos, fenthion, fenitrothion remained practically unchanged. The two selected strains were slightly less susceptible to pyrethrins and organophosphorus fungicides such as IBP and edifenphos. Rc and Rp strains showed a resistance pattern relatively similar to that of the T population, indicating that resistance factor(s) did not vary during the 12 generations when the rice brown planthopper population which had acquired a certain level of organophosphorus and carbamate resistance was continuously selected with carbaryl or propoxur.

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The oriental chinch bug, Cavelerius saccharivorus OKAJIMA (Hemiptera: Lygaeidae) was reared on grasses of maize, Kentucky blue grass, sorghum and sugarcane. Among these four diets, blades of sugarcane were found to be most suitable for the easy and successive rearing of the bug. The bug was reared successively for more than two generations with a 40% emergence in the second generation. It was also observed that females laid fertile eggs on a wax paper surface as well as on sugarcanes.

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Beauveria amorpha was isolated from the larvae of Anomala cuprea and Anomala costata reared in the soil collected from Nagano Prefecture. Its cultural and morphological characters were investigated.

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A sex-attractant pheromone was found to be secreted by females of the soybean beetle. Anomala rufocuprea MOTSCHULSKY (Coleoptera: Scarabaeidae). The pheromone was collected on Tenax GC and Porapak Q and recovered with hexane. A laboratory bioassay method based on the orientation behavior of walking males in a glass tube was established.

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