A quantitative evaluation of the influences of weather and moonlight conditions on the light trap catches of moths was needed to compare samples of different stands and time.Multiple regression analysis was employed to establish which factors were important in determining the collected number of species and individuals and other characteristics of a moth sample. Data of seventeen August samplings taken from 20 : 00-21 : 00 and the weather and moonlihgt conditions prevailing at that same time were used. Regression analyses showed that most of the variation in the number of collected species could be described by an equation involving wind velocity, fog density, change in temperature from the previous night and lightness of the sky during the night. Standard partial regression coefficient showed that fog density was the most important positive effect component and wind velocity the main negative effect component. The equation for estimating the number of collected individuals described a smaller portion of the variability than the number of species. Air temperature did not significantly affect either the number of species or individuals.

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Hybrid F₁ progenies were produced from matings between Cletus punctiger and C. rusticus in the laboratory. Seventy-eight and three-tenths percent of C. punctiger females which mated with C. rusticus males produced fertile eggs, while 45.0% of C. rusticus females mated with C. punctiger males produced fertile eggs. Several characters of the hybrid F₁ were compared with those of the parent. Considering these characters overall, F₁ hybrids seemed to be intermediate between the parent species. These hybrids were able to copulate and to produce eggs, but they were thought to have no fertility from several selfed and back-crossed tests.Of 253 mating pairs observed in a field cage in whcih 50 males and 50 females of the two species were released, 11.5% were interspecific and most of the intraspecific matings were observed on the preferred host plant of each species. It was suggested that bugs of the two species do not mate at random but that they have some mechanism(s) to recognize conspecific mates.

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The effects of L-glutamic acid, quisqualic acid, L-aspartic acid, acetylcholine, curare, atropine, chlordimeform, nereistoxin, fenitrothion and fenitroxon on EPSP at the neuromuscular junction of the larval mealworm, Tenebrio molitor, were studied using a microelectrode technique. Applications of L-glutamic acid, quisqualic acid and L-aspartic acid suppressed 50% of EPSP at concentrations of 4.2×10^-5 M, 2.3×10^-5 M and 1.2×10^-3 M and evoked a depolarization of muscle membrane with this EPSP reduction. However, acetylcholine at 2×10^-3 M did not suppress EPSP but evoked a depolarization of the muscle membrane. Atropine, curare, nereistoxin and chlordimeform at a concentration of about 2×10^-3 M suppressed 50% of EPSP. From a pharmacological aspect these results suggest that L-glutamic acid is an excitatory transmitter at the insect neuromuscular junction, because L-glutamic acid and quisqualic acid, its agonist, revealed the effect at forty and eight-fold lower concentrations than other drugs, respectively.

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The contents of S-propenylcysteine sulfoxide (PCSO) in roots and exudates of aseptic onion seedlings, and the total root bacteria counts in septic seedlings were all higher in cultivars that are susceptible to the onion maggot, Hylemya antiqua MEIGEN, than in the resistant ones. In addition, more propylthio oviposition attractants were generated in the susceptible cultivars. In aseptic soil where bacterial metabolism was impossible, PCSO accumulated.In vitro metabolism of the PCSO extract of onion by bacteria produced more methylthio compounds than propylthio compounds, which was in contrast to allinase metabolism in chopped onions. Since intact septic onion seedlings generated these compounds in intermediate proportions, it is suggested that both bacterial metabolism of exudates in soil and activation of alliinase by bacterial decompartmentalization are simultaneously taking place in the onion rhizosphere.

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Overwintering adults of the Bombay locust, Patanga succincta (L.), were collected in the outbreak year (1980) from two adjacent areas in the southern part of Okinawa Is. and their morphometric characters were examined. The number of eye stripes was either 7 (6-instar type) or 8 (7-instar type). The proportion of the 7-instar type in the females (70.7%) was significantly higher than in the males (18.6%). The head width (C), lengths of hind femur (F) and elytron (E) in each sex were all significantly greater in the 7-instar type than in the 6-instar type. However, these differences were much smaller than the sexual differences.The means of F/C (4.31-4.40) and E/F (1.61-1.65) were not significantly different between the two instar types in each sex.These results are discussed in relation to moulting polymorphism in locusts and grass-hoppers.

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An outbreak of Crypticerya jacobsoni (GREEN) was encountered on Rakata Besar, one of the Krakatau Islands, which are situated in the Sunda Strait between Java and Sumatra and are known to have been totally sterilized in 1883 by the world-famous big eruption. A huge number of leaves and twigs of various plant species were found to be infested by many adult females and larvae of the insect. They were most abundant on Ficus fistulosa and followed by Pipturus argenteus. Nearly 100% of their leaves were infested. Such a scene was encountered in almost every place on Rakata Besar, but scale insect was relatively few on the three other neighbouring islands.

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The tick Ixodes asanumai parasitic on the lizard Eumeces okadae, showed a selective parasitism in respect of the size and sex of hosts and the attachment site for blood-sucking. In Miyake-jima, 21.0% of lizards were on the average infested by female ticks. Mature male lizards received the most intensive infestation, probably because of their high activity in the mating season. On the average, 67, 9%and 22.4% of lizards were infested by larval and nymphal ticks, respectively. In all stages of ticks, the infestation level increased with the lizard size. Almost all female ticks selectively attacheced on the knee of lizard's forelegs. In contrast, the larval ticks generally attached on the toe of legs and nymphs on the trunk. This stage specific selection of attrachment sites was reconfirmed by the feeding experiment under the laboratory conditions. The histological observation revealed that the female tick parasitism caused the atrophy of muscle fibers of the lizard's foreleg.

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In order to know whether the "active space model" for male orientation to a pheromone source, which was developed by NAKAMURA and KAWASAKI (1977), can be applied to a situation of fluctuating wind conditions during short periods Spodoptera litura male catches in a pheromone trap during 10 min periods were analyzed. Males did not come continuously to the trap but did come intermittently, the longest period when none were attracted being during 5 or 6 min. The wind velocity changed from a high to a low level during these periods.The active space model was modified to apply to a situation of fluctuating wind velocity, and catches obtained experimentally from different release points from the trap were compared with those obtained from a computer simulation using this model. In more than half the cases experimental results differed significantly from the simulated results. Thus, the active space model, which does not describe instantaneous pheromone behaviour, is not really applicable to fluctuating wind conditions during short periods. However, the distance within which released males were captured in the trap was not greatly different between experimental and simulated results except at the time of weak wind. These facts led to the conclusion that this model is valuable in representing the "time-average" active space (or pheromone plumes) during a certain period.

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The life history of the azuki bean weevil, Callosobruchus chinensis LINNE in the field, especially the process of weevil emigration from store to field has not been made clear. The mechanism of the emigration process was analyzed with specially designed apparatus in the laboratory. The presence of beans firmly suppressed emigratory activity in the first five days of adult life. The supplied diet (saccharose solution and yeast) moderately suppressed the emigratory activity, especially of older weevils. Males emigrated density-independently throughout their longevity, while females emigrated density-dependently until the fifth day and thereafter density-independently. Supply of the diet after different periods of starvation resulted in elongation of longevity and recovery of fecundity. When the diet was supplied on the first to third day after emergence, the total number of eggs and mean longevity were two and three times, respectively, as many as the control for whom no diet was supplied for adults. When diet was started on the fifth day, the fecundity in two days increased to the same level as when the diet was started just after emergence. The diet supplied adults nine days after emergence did not result in an increase of either fecundity or longevity.

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Some biological effects of anti-juvenile hormone active compound, 1-citronellyl-5-phenyl-imidazole (KK-22), on the 3rd instar silkworm, Bombyx mori L., were investigated by feeding treatment with artificial diet for successive days of the 3rd instar period. Drastic precocious metamorphosis was induced in response to doses of KK-22 : 100% at 50-200 ppm, 95% at 25 ppm, and 45% at 12.5 ppm in the diet. Some 3rd instart larvae ingesting diet containing 50 to 200 ppm of KK-22 were metamorphosed to pupae within the same instar stage; they spun to make cocoons and pupate, but failed in adult emergence. The larval development of the treated 3rd instar silkworms was prolonged for 1 to 5 days, accompanied by a gain of body weight exceeding the controls. The induction of precocious metamorphosis seems to correlate with prolongation of the larval developmental period in the 3rd instar.

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Peroral administration of toxic crystals of Bacillus thuringiensis to larvae of the silkworm, Bombyx mori, resulted in the inhibition of rhythmic contractile movements of the midgut.The paralysis began in the second-fourth of the midgut. The affected region was extended to the entire midgut except for the posterior end. Recovery from the midgut paralysis occurred in larvae which survived the exposure to the toxin. The time interval intervening between the administration of the toxin and the midgut paralysis became shorter as the dose increased. The interval varied depending on the subspecies of B. thuringiensis which produced the toxic crystal. The administration of activated toxin resulted in an earlier manifestation of paralysis in a wider portion of the midgut. The optimum condition for activating the toxin differed with the different subspecies of B. thuringiensis. The toxin caused midgut paralysis in the presence of tetrodotoxin.

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Some biological and chemical nature of the dispersion-inducing substances of Blattella germanica was studied by preference tests for the first instar nymphs of the same species and by gel filtration chromatographies.As the results, either the saliva collected from the mouth parts and the salivary reservoir or the crop content and its turbid counterflow from the mouth parts showed repellency.The sex, stage, and species specificities of the substances were lax when examined with the saliva of B. germanica, Periplaneta americana, and P. fuliginosa.The dispersion-inducing substances were soluble in water and heat stable but not extractable with organic solvent. The substances were partially purified on Sephadex G-25 and G-100 gel filtration column chromatographies; they were cluted into at least two different molecular weight fractions. Their molecular weights were estimated to be about 70, 000-100, 000 and less than 5, 000; they were supposed to have proteinaceous nature.

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Six species of scale insects and three species of aphids as well as their parasitoids were recorded from citrus orchards in Brasilia D.F. in the Cerrados region in January-February 1982. The parasitoids recorded from scale insects are as follows : Five species from Chrysomphalus fucus, one species from Lepidosaphes beckii, four species from Pinnaspis aspidistrae, and one species from Coccus viridis. Effective control of Ch. ficus can not be achieved by any parasitoids found in the Cerrados area. It is suggested that Aphytis holoxanthus be introduced into citrus orchards in the Cerrados area from areas in Brazil where the parasitoid has been established after importation in 1962. Since effective parasitoids of C. viridis have not been found, effort should be directed toward discovery of a beneficial species in Brazil, which is presumably the source country of the pest. No parasitoids of Toxoptera citricidus were found in the Cerrados area. It is suggested that the parasitoid, Lysiphlebia japanica be introduced into Brazil from Japan, where the parasitoid has been reported as the most effective natural enemy of the aphid.

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Biological activities of 26 analogues of 10-methyldodecyl acetate, a sex-pheromonal component of the smaller tea tortrix moth, were evaluated under field conditions. 9-Methylundecyl acetate and other several analogues were good substitutes for 10-methyldodecyl acetate indicating a relatively low structural specificity of particular pheromonal component in the multi-component pheromone system.

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