p-Anisaldehyde, a common flower volatile component, was found to be a potent attractant to adults of the varied carpet beetle, Anthrenus verbasci, irrespective of sex. The male catch with p-anisaldehyde (1 g) was almost the same as that with the female sex pheromone (1 mg), but the female catch was significantly larger. The catch with the combined attractant (p-anisaldehyde+the sex pheromone) was almost the same as the sum of the catches with each single attractant. Among 22 related compounds, two positional isomers and 20 functional-group-substituted compounds, p-anisaldehyde dimethylacetal, p-methoxyphenylacetone and p-ethoxybenzaldehyde were almost as attractive as p-anisaldehyde.

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A total of 71 fecal samples, collected from 56 animal species (47 mammals, four reptiles, and five avians), were examined for the occurrence of Bacillus thuringiensis. Most of the animals were residents of the Fukuoka Municipal Zoo, Fukuoka, Japan. The organism was detected in 32 (45%) samples. Among 2, 955 colonies of the Bacillus cereus/B. thuringiensis group examined, 531 (18%) were assigned to B. thuringiensis on the basis of the formation of parasporal inclusions. Fecal samples from animals feeding on vegetable matter contained B. thuringiensis at high frequencies. Examples included feces from the chimpanzee, gorilla, Japanese black bear, polar bear, green iguana, and ostrich. In contrast, only a few isolates were recovered from feces of carnivorous animals, in particular, feline mammalians including the lion, tiger, leopard, and jaguar. The results suggest that a daily food intake of plant origin yields the feces containing B. thuringiensis at high levels.

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During observations from September to November, flight activity of Lyonetia prunifoliella malinella occurred in the morning and in the evening outside the crowns of apple and shelter trees. The morning flight started about half an hour before sunrise. About 15 min later, the number of flying moths increased rapidly and swarms formed. The swarms lasted for about half an hour. Although females were present in the tree crown, they did not participate in the swarms, which were composed only of males. Mating began during the time when the males were swarming, and most of the mating pairs separated by noon. The evening flight started around sunset. It did not develop into swarms and finished in about half an hour. The evening flights were composed of both males and females, with the latter including both virgin and fertilized females. During the evening flight, it was noted that some moths were flying out of view. Simultaneously it was found that the moths flying into view alighted on the shelter trees. Thus, flight in the morning was considered to be associated with mating, while that in the evening with dispersal.

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The induction and termination of pupal diapause of Helicoverpa armigera were examined in three local populations from Kagoshima, Okayama and Ishikawa in Japan. Pupae in diapause retained eyespots for much longer than non-diapause pupae, and for markedly diverse durations. Once eyespots disappeared at the end of diapause, the period required for development until eclosion was more or less constant at 18°C. In all experiments repeated twice under the same conditions, male pupae generally showed a high tendency to enter diapause while female pupae showed a slight and rather population-specific tendency towards diapause. This trait as well as the higher intensity of male pupal diapause and the shorter post-diapause period of females suggest that females emerge first in the field in spring. This feature was regarded to be potentially important for considering the life-history strategy of this cosmopolitan pest.

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The responses of two insect predators of spider mites, Scolothrips takahashii (Thysanoptera: Thripidae) and Oligota kashmirica benefica (Coleoptera: Staphylinidae), to volatile compounds from leaves treated with aqueous jasmonic acid (JA) and/or gaseous methyl salicylate (MeSA) in an olfactometer were examined. Adult females of O. kashmirica benefica exhibited a significant preference for JA+MeSA-treated leaves when compared with uninfested leaves. In contrast, adult females of S. takahashii significantly preferred MeSA- and JA+MeSA-treated leaves to uninfested leaves. Neither predator showed any preference for JA-treated leaves when compared with uninfested leaves. The results argue in favor of manipulating the behavior of natural enemies of herbivores as a method of biological control against herbivorous pests in agroecosystems. This is the first report to suggest that MeSA can be a useful tool for enhancing the effectiveness of carnivorous natural enemies of spider mites.

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The effects of food availability and age on the reproductive traits of Pomacea canaliculata were determined in snails fed at three food levels under laboratory conditions (14L:10D; 25°C). In males, copulation frequency tended to increase with age, while food availability did not affect copulation frequency. In females, spawn production was lower in food-limited conditions, but current or weight-specific reproductive effort (RE) did not differ among food levels. The weight-specific RE and spawn frequency of the well-fed females decreased with age, but their current RE increased with age.

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The host plant suitability of the solanaceous wild herb Solanum japonense as an alternative larval food for the three non-pest species of the Epilachna vigintioctomaculata complex, namely E. niponica, E. pustulosa, and E. yasutomii, was investigated under laboratory conditions. Three larval developmental traits (eclosion rate, developmental duration, and body size) were recorded together with the leaf area consumed throughout the developmental stages. All three ladybird species showed sufficient performance on S. japonense, although the suitability of S. japonense for larval development appeared to be highest for E. pustulosa and lowest for E. yasutomii. The measurements of leaf consumption revealed that E. niponica and E. pustulosa consumed a significantly larger leaf area of S. japonense than did E. yasutomii during the developmental stages. However, when the influence of interspecific body size difference was removed, leaf consumption was significantly smaller in E. niponica than it was in the other two species, suggesting a higher feeding efficiency of E. niponica upon digesting S. japonense leaves.

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A temporally structured model that enables simulation of the development of the west Japan type yellow-spotted longicorn beetle, Psacothea hilaris (Pascoe), at different locations was developed. Life history parameter values incorporated into the model were estimated by laboratory rearing experiments. To validate the present model, the development of eggs laid monthly from June 1 through November 1 was simulated under dynamic temperature and photoperiod conditions at Ayabe City. The individuals laid on June 1 did not enter diapause but emerged in early August of the same year. On the other hand, about 2/3 of the individuals laid on July 1, and all those laid on August 1 and September 1 entered diapause (or quiescence), and started to emerge in late May of the following year. Individuals laid on October 1 and November 1 overwintered as young larvae (1st–3rd stadia) and eggs, respectively, and the majority of these emerged in late July–early August. Interestingly, the remaining individuals entered diapause in the 2nd year and emerged in June of the 3rd year. Analyses of these simulation results suggested that concentrated emergence of P. hilaris can occur twice in one year (in late May–early June and in late July–early August) at Ayabe, and this is fairly concordant with known adult prevalence at this location considering the long life-span of adults. It was also suggested that although P. hilaris at Ayabe has basically a univoltine life cycle with a facultative diapause, varying proportions of the population appear to have a bivoltine life cycle or a semivoltine life cycle depending on the meteorological conditions of that year. The life cycle of P. hilaris is suggested to be very flexible and adaptive to environmental fluctuations.

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Members of the genus Termitaria are entomogenous exoparasitic deuteromycetes growing on the exoskeleton of various species of termites. Distinguished by sporodochial surface color, three types of Termitaria were found from six termite species of four genera from various localities in Japan: Black-type, White-type and Intermediate-type. Molecular phylogenetic analysis focusing on the genetic lineage of Termitaria, using sequences of the nucleotide 18S rRNA gene, suggested that these three types were actually different species. The resultant phylogenetic tree of Termitaria did not show any contradiction to the topology known in the host phylogeny. This suggests that there is a parallel cladogenesis between the hosts and fungi, and that there has been scarcely any detectable horizontal transmission of fungi between the host species. The only exception was found in Yakushima Is., where Black-type may have changed its host from Hodotermopsis japonica to Reticulitermes speratus.

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A soybean variety ‘Adams’ is known to be resistant to soybean dwarf disease. The number of nymphs and survival rate of Aulacorthum solani decreases remarkably on ‘Adams’. To understand the resistant mechanism of ‘Adams’, we compared the feeding behavior of A. solani adults on resistant ‘Adams’ and susceptible ‘Suzukari’ soybean varieties using an electronic monitoring system (EMS). On ‘Adams’, two ingestion waveforms, the Irss and the Is waveform were observed. The Irss waveform was recorded just after the S waveform, suggesting ingestion from non-phloem. This waveform was not observed on ‘Suzukari’. A. solani on ‘Adams’ probed frequently and repeated short-term phloem ingestion, while A. solani on ‘Suzukari’ ingested from phloem continuously for a long period. Consequently, the total phloem ingestion time was shorter on ‘Adams’ than on ‘Suzukari’. These results suggest that a decrease of ingestion from phloem on ‘Adams’ causes a reduction of nutrient uptake in quality and quantity, and eventually a decrease in survival rate, reproduction and development of A. solani.

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A cecidomyiid species found in 1989 in orchid greenhouses on Okinawa Island, Japan, is identified as Contarinia maculipennis, a polyphagous Southeast Asian pest. This species is distinguished from other congeners by the uneven circumfilar loops of the male flagellomere, the relatively long female first flagellomere, and the spiracles of the larval eighth abdominal segment at the end of the posteriorly directed lobes. C. maculipennis was intercepted at Narita Airport, Japan, in 2000 and 2001 with orchid flowers imported from Southeast Asian countries. We emphasize caution about recognizing the possibility that this polyphagous gall midge could infest cash crops other than orchids on Okinawa Island.

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A gall midge species producing circular blisters on mango leaves was found in 2000 at Tamagusuku Village on Okinawa Island, Japan. This gall midge is identified as Procontarinia mangicola (Shi), and was originally placed in the genus Erosomyia. Another species, Procontarinia schreineri Harris, described from Guam is newly synonymized with P. mangicola. By 2001, this gall midge was found on eight islands in Okinawa Prefecture. Heavily galled leaves fell to the ground much earlier than usual and mango trees with galled leaves had almost no inflorescences, resulting in low yields of mango fruit. We consider that the gall midge adults might be dispersed by wind or that the larvae could be transported with soil or other substrates covering the roots of mango plants in nurseries. We also provide some comments on control measures that may be used against this gall midge.

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The life history of the white grub Dasylepida sp. was surveyed in a sugarcane field in Miyako Is., Okinawa, Japan. Adult flights were observed from early February to mid-March in 2001. Adults commenced flight just after sunset (at around 18:30) and mated. Sampling from the pots placed in the field on 19 April yielded 41.8% eggs and 58.2% first stadium larvae. Larvae sampled on 20 June, 2000 were found to consist of 33.3% and 66.7% of the first and second stadium larvae, respectively. On 22 August, 87.5% of larvae were second stadium and the remainder (12.5%) were third stadium larvae. The proportion of third stadium larvae increased and attained 100% by 30 November. In an excavation survey on 26 November, 2001, 11 adults (three females and eight males) and five pupae were found in the soil at a depth of around 45 cm. Pupae were found in the tunnel cavities. We believe that adults remain in the tunnels until the next February. In the rearing experiments at 25°C in the laboratory, the egg period was 23.6 d and the larval periods of the first, second and third stadia were 80.9, 91.8 and 335.8 d, respectively. These facts indicated that Dasylepida sp. has a two-year life cycle.

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The species composition and seasonal occurrence of spider mites and their natural enemies were compared in three Japanese pear orchards with different control pressures, from 1996 to 1999. The orchards were an agrochemical-free orchard, a pesticide-free orchard, and a conventionally controlled orchard. The differences in the dominant species of spider mites and phytoseiid mites among these three orchards were observed. Among the spider mites, Amphitetranychus viennensis was dominant throughout the four years in the agrochemical-free orchard whereas Panonychus citri was dominant in the pesticide-free orchard. In the conventionally controlled orchard, the dominant spider mite species was Tetranychus urticae, except for in the year 1998. The dominant phytoseiid mites were Amblyseius orientalis and Amblyseius sojaensis in the agrochemical-free orchard, Typhlodromus vulgaris in the pesticide-free orchard, and Amblyseius californicus in the conventionally controlled orchard. The predacious insects of spider mites which were abundant in the three orchards were Stethorus japonicus, Oligota spp., Scolothrips takahashii, and Feltiella sp. Unlike the spider mites and phytoseiid mites, the dominant species of predacious insect varied greatly from year to year within each orchard. This suggests that the species composition of the predatory insects may be less affected by agrochemicals than that of spider mites or phytoseiid mites. Differences among the peak densities of spider mites among the orchards seemed to be due to differences in the dominant spider mite species rather than to differences in control pressure with chemicals. The peak density in the orchards where P. citri was dominant was higher than in those where A. viennensis or T. urticae was dominant, nevertheless the predacious insects occurred in all orchards. This suggests that the predacious insects would be less effective in suppressing P. citri than in suppressing T. urticae and A. viennensis.

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We studied the seasonal occurrence of the eriophyid mites in the domatia of Cinnamomum camphora leaves and the predatory mite, Amblyseius sojaensis, near the domatia. The eriophyid mites increased in number in June, followed by an increase of A. sojaensis. The number of A. sojaensis near the domatia was significantly higher when the eriophyid mites were present in the domatia than when they were absent from it. When the domatia entrance was experimentally filled with glue to prevent the eriophyid mites from being preyed upon, the density of A. sojaensis was significantly reduced. These results showed that the density of the eriophyid mites that inhabit the domatia affect the density of the predatory mite, A. sojaensis, that do not inhabit the domatia.

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Six minor secretory compounds: phenol, p-cresol, guaiacol, methyl benzoate, benzaldehyde dimethyl acetal and creosol have been identified from a methanol extract of the millipede Chamberlinius hualienensis Wang at the 7th nymphal and adult stages of reproductive migration. These compounds, except for methyl benzoate, were detected for the first time from C. hualienensis. Almost all female nymphs contained greater amounts of the compounds than male nymphs. In females the amounts of methyl benzoate and guaiacol remarkably decreased with development of the nymphal stage. Although only a defensive role has been postulated for millipede secretions, such a quantitative change in secretory compounds at the reproductive migration stage suggests they may possibly have a significant physiological function related to reproduction and/or development.

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Embryonic development in relation to life cycle adaptation was studied in the northern (Aomori, 40.6°N) and southern (Osaka, 34.9°N) strains of Eobiana engelhardti subtropica (formerly Metrioptera hime) (Orthoptera: Tettigoniidae). Eggs of the 2 strains showed similar thermal responses. At 20, 22.5, and 25°C, they developed to the mature embryonic stage without delay and entered an obligatory embryonic diapause (final diapause). At 27.5 and 30°C, on the other hand, embryonic development was markedly delayed. This retardation was more striking in the southern strain. Especially, summer diapause occurred in half-grown embryos at 30°C. A shift of temperature from 30°C to 20 or 25°C terminated summer diapause and the eggs started to develop. The final diapause is never terminated if kept at high temperatures. Final diapause requires an exposure to a cold temperature of 15°C or lower and the intensity is higher in the southern strain. Adults of the southern strain emerged in mid June or earlier and those of the northern in early-mid July. In outdoor experiments, the developmental rate decreased more conspicuously in the eggs laid earlier in the southern population. As a result, the eggs reached the final-diapause stage in autumn more synchronously than expected from the long egg-laying period. The decreased developmental rate and summer diapause appear to secure survival in the hot season and ensure reaching the embryonic diapause stage synchronously in autumn. The local variation in the final-diapause intensity seems to be related to the heat units in autumn which might otherwise cause untimely hatching.

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We previously reported that lipophorin, an insect lipoprotein, is essential for in vitro development of the larval endoparasitoid Venturia canescens from the 1st larval instar to the 2nd instar. In this study, we compared the effect of various lipoproteins from insects and vertebrates to clarify whether the growth promotion effect of lipophorin is caused by its lipid moiety. As well as the permissive host (the greater wax moth) lipophorin, lipoproteins from a nonpermissive host (the silkworm) and vertebrates (chicken and human) also promoted V. canescens development to the 2nd larval instar, suggesting that essential factors for the first larval ecdysis are ubiquitous in a wide range of animals. When total lipids from the permissive host were emulsified in a lipoprotein-free medium with multilaminar vesicles of phosphatidylcholine (liposome), V. canescens larvae underwent ecdysis in the medium. In contrast, lipophorin lipid-depleted by lipase treatment promoted larval growth less than intact lipophorin. These results indicated that the growth-promotion effect of lipophorin is mainly due to the lipid moiety of lipophorin.

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The polymorphic patterns of genomic DNA amplified by RAPD-PCR were detected in laboratory-cultured populations of sweet potato weevils, Cylas formicarius collected from the Southwest islands (Nansei-Shoto) of Japan. When three sets of primers, T13/T13, T05/T05 and T01/T07 were used for PCR, the polymorphic patterns of the amplified DNA were classified into nine types. Of these types, A₁B₁C₃ was common in all populations tested. The present study determined the useful primer sets that will enable the successful classification of sweet potato weevils based upon the polymorphic patterns of genomic DNA amplified by RAPD-PCR.

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A gregarine parasite of the flea beetles, Phyllotreta undulata and P. atra is reported and described as Gregarina phyllotretae Hoshide 1953. Gregarine infection was observed in all localities investigated during the study. Infection in the P. undulata population was always higher than that in the P. atra population. Maximum infections of both insects were recorded in August. Measurements of trophozoites, sporadins and syzygy forms of G. phyllotretae, new hosts, distribution, occurrence and prevalence in Turkey are reported in this paper.

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The effect of environmental factors on the overwintering success of Pomacea canaliculata in the northernmost population of Japan was examined to determine the location of overwintering habitats in the agricultural water system. The snail overwintered only in a portion of the water canals, and did not overwinter in dried paddy fields. In the canal, the density of the snail was not necessarily high at the overwintering site before winter. Overwintering success in the water canal was not explained by temperature and water velocity, but by pH, dissolved oxygen (DO) and depth of water among the sampling sites. To determine the location of a proper overwintering site, it is important to investigate various habitats including places where the snail density is low, and measure various environmental variables including pH, DO, and depth of water.

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We evaluated the viability of Sclerotium cepivorum Berk. (causal agent of of garlic and onion white rot) mycelial and sclerotial fragments transported through excreta of Rhizoglyphus robustus Nesbitt fed on S. cepivorum. Excreta were obtained from mites fed on 1) mature, hydrated and fragmented sclerotia (mhfS); 2) mature, dehydrated and fragmented sclerotia (mdhfS); 3) whole mature sclerotia (wmS); 4) mycelium (M) and 5) potato dextrose agar culture media (PDA). After feeding, mite excreta were examined under compound and scanning electron microscopes for the presence of mycelial and sclerotial fragments. S. cepivorum mycelium growth and sclerotia formation were observed in three out of 60 excreta pellets from mites fed on M and mhfS and only in one excreta pellet out of 60 from mites fed on mature, dehydrated and fragmented sclerotia (mdhfS). Numerous fragments of mycelia and sclerotia on the mites' bodies, mainly on the sense organs of the ambulacral appendages and the mouthparts were identified by compound and scanning electron microscope observations. R. robustus may also influence white rot epidemiology as a consumer of S. cepivorum and spread and/or transmit the pathogen by carrying fungal fragments on its body externally.

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