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To evaluate the infection risk of Anoplophora malasiaca(Thomson) (Coleoptera: Cerambycidae) in two species of Japanese pine bonsais (Japanese black pine and Japanese white pine), feeding and oviposition preferences of female A. malasiacato pine bonsai and mandarin orange were examined. A female was released into a net cage together with a pair of one pine bonsai and one mandarin orange. All mandarin oranges used in preference tests were damaged by feeding and deep biting scars from females, and larval frass ejection from the trunk was found in some mandarin oranges within 4 months of observation. However, these scars were found on only a few pine bonsais, and frass ejection was not found in any pine bonsais. No A. malasiacalarvae were detected in these pine bonsais. Therefore, frass ejection from trunks might be indicative of the presence of larvae. In field surveys at bonsai nurseries, no A. malasiacaadults were found on the pine bonsais and no pine bonsais exhibited frass ejection. Statistical analyses of these results suggested that the risk of A. malasiacainfestation in pine bonsais could be ruled out as a negligible level by confirming an absence from the trunk of frass ejection.

The red-necked longicorn beetle Aromia bungii(Faldermann) (Coleoptera: Cerambycidae) is an emerging invader in Japan and has become a major pest of cherry blossom trees, peaches, prunes and Japanese apricots. The male-produced aggregation-sex pheromone, recently identified as (E)-2-cis-6,7-epoxynonenal, has two enantiomers. Here, we determined which enantiomer the male produces and tested the responses of beetle antennae to the enantiomers using electroantennography. The male produced only the (6R,7S)-enantiomer, but both enantiomers elicited responses from the antennae of female beetles. Antennae of males also responded to both enantiomers. In field trials, the (6R,7S)-enantiomer and the racemic mixture were equally attractive to both sexes of the beetle, whereas the unnatural (6S,7R)-enantiomer did not attract any beetles.

The red-necked longicorn beetle, Aromia bungii(Faldermann) (Coleoptera: Cerambycidae), which has recently invaded Japan, is a serious pest species. The larvae kill cherry and orchard Rosaceae trees, such as peach, plum, and apricot. To clarify their features for mate location, male and female flight behaviors were observed in wind tunnels with caged males and females as lures. In a small wind tunnel (50 cm in diameter, 2 m in length), both sexes showed takeoff behavior according to increasing airflow. The rate of female takeoff against the male lure, a live male in a wire-netting cage, tended to be higher than for other combinations. In a large wind tunnel (ca. 1.6 m in diameter, 4 m in length), both sexes ascended and showed momentary hovering and astatic flight. When male lure cages were placed windward in the wind tunnel, females showed “upwind flight,” while males did not. It is assumed that females were induced to fly upwind by a factor derived from live males, likely to be an airborne pheromone component.

The white grub beetle Dasylepida ishigakiensisNiijima et Kinoshita (Coleoptera: Scarabaeidae) is a serious sugarcane pest on the Miyako Islands, Okinawa, Japan. Because this beetle stays underground for most of its lifetime, mating disruption using a synthetic sex pheromone has been suggested as a promising control measure. The amount of pheromone (2-butanol) released by the females is known to decrease drastically as they repeat calling each day. In this study, we determined the response of males to different concentrations of (R)-2-butanol, both in the laboratory and in the field. Males showed typical pre-mating behaviors and they were attracted to (R)-2-butanol even at a concentration 1/100 of the amount typically emitted by a female during the 1st period of calling. We examined whether female attractiveness to males was reduced with the frequency of calling, by counting the number of males attracted to females that had called during zero to five periods beforehand. Our results indicated that a high level of female attractiveness was maintained even after three periods of calling. Based on these findings, we propose that releasing synthetic sex pheromone shortly before the start of the mating season and into the late mating season may be optimal for disrupting the mating of this beetle.

The effect of mating disruption by the ground-surface application of 2-cm-long dispensers (mini-dispensers) of 2-butanol against the white grub beetle Dasylepida ishigakiensisNiijima et Kinoshita (Coleoptera: Scarabaeidae) was examined in sugarcane fields on the Miyako Island, Okinawa, Japan. Mating rates and male catches with sex pheromone traps were reduced to a low level comparable to that obtained from a conventional method in which rope dispensers (25 m) were hung at a height of ca. 30 cm along the sugarcane ridges. Both mating rates and male catches were reduced with increasing number of treated mini-dispensers. These results suggest that by using mini-dispensers the amounts of synthetic sex pheromone and plastic resin can be reduced to 1/10–1/5 and 1/6–1/3, respectively, of their conventional application with rope-type dispensers, without impairing the efficiency of mating disruption in this beetle. Furthermore, the amount of labor required for the application of this method is expected to be greatly reduced compared to the rope-type dispenser method.

We investigated physical and chemical cues involved in male mating behavior of the white grub beetle, Dasylepida ishigakiensis (Scarabaeidae). When presented with female attractant pheromone ( R)-2-butanol lures in a flight tunnel, nearly all males exhibited orientation and touching behaviors to freshly killed males and females and to intact glass models. Males landed and bent their abdomens on male and female bodies, but not on intact glass models. When treated with one female equivalent (FE) extract, washed immature male bodies and glass models both evoked stronger male responses than untreated equivalents, with the former eliciting a greater response than the treated glass models. Male responses to target male and female bodies decreased with increased numbers of washings of target bodies with organic solvents. These results suggest that the chemical factors that elicit male abdominal bending behavior are present on the body surface in both sexes. Washed immature male bodies treated with 1 FE or one male equivalent (ME) of extract induced strong male abdominal bending behavior. Washed mature female bodies treated with 1 ME extract also evoked male responses. Extracts of both sexes included factors eliciting male abdominal bending behavior. These results suggest that both physical and chemical cues derived from conspecifics cooperate to facilitate male mating recognition in D. ishigakiensis. The mating process of this species in the field is highly synchronized. Thus, after orienting to a female-like object, the only information males require by touching is whether the sex attractant pheromone that attracted them is indeed from a conspecific. [ABSTRACT FROM AUTHOR]