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An emerging invader, the red-necked longicorn beetle Aromia bungii (Faldermann) (Coleoptera: Cerambycidae), has become a major pest of cherry blossom, peach, prune, and Japanese apricot in Japan. The synthetic aggregation-sex pheromone, (E)-2-cis-6,7-epoxynonenal, has been used as a chemical for their monitoring. The longevity of the current lure is, however, only one week. Unlike most Lepidopteran lures, it needs to be emitted in large amount of the pheromone emission for effective attraction. In this study, we surveyed chemical retention materials to determine which improving its longevity. The weights of 7 types of lures were measured for 2 or 3 weeks to determine the weight-loss. The pheromone emission from each lure tended to be correlated to the weight-loss. We analyzed the pheromone emissions from candidate lures for three weeks and compared them to the current lures. The current lure continued pheromone emission for 7 d, whereas the candidate lure continued for 14 d. In field trials, the candidate and current lures were both significantly attractive during the first week compared to the control. However, the candidate lure attracted the beetle to the same extent for over 14 d; its longevity was double that of the current lure, therefore, it could be useful for extended monitoring of this beetle. [ABSTRACT FROM AUTHOR]

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. malasiaca to 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. malasiaca larvae 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. malasiaca adults were found on the pine bonsais and no pine bonsais exhibited frass ejection. Statistical analyses of these results suggested that the risk of A. malasiaca infestation in pine bonsais could be ruled out as a negligible level by confirming an absence from the trunk of frass ejection. [ABSTRACT FROM AUTHOR]

Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae) is a serious pest that affects various crop trees and landscapes in Japan. We collected and analyzed volatiles from male and female A. malasiaca. 4-(n-Heptyloxy)butan-1-ol and its aldehyde, pheromone components in A. glabripennis and A. chinensis, were detected in the male volatile extracts and nonanal both in the male and female volatile extracts. Nonanal was absent from the extracts of twigs of the willow host plant. Gas chromatograph-electroantennographic responses showed that nonanal and 4-(n-heptyloxy)butan-1-ol elicited responses from both male and female antennae, but 4-(n-heptyloxy)butanal did not. Volatiles of eight artificially reared males, analyzed every 3 or 4 days for 60 days from adult emergence showed that they all produced nonanal and 4-(n-heptyloxy)butan-1-ol. The two compounds produced no short-range female attraction but in males, the short-range attraction to nonanal was dose dependent and significant in a higher dose, but did not depend on 4-(n-heptyloxy)butan-1-ol. When wounded willow twigs were added to nonanal and 4-(n-heptyloxy)butan-1-ol, the frequency of male responses was higher than in all other treatments, but the same as wounded willow twigs alone. The wounded host plant willow twigs might thus be enough for male attraction. The identified volatiles from the beetles in the present study might have a weaker function for attraction from the distance compared to their host plant volatiles. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The white grub beetle Dasylepida ishigakiensis Niijima 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. [ABSTRACT FROM AUTHOR]

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 ishigakiensis Niijima 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. [ABSTRACT FROM AUTHOR]

The feasibility of mating disruption with synthetic sex pheromone for the control of the white grub beetle Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) was examined by permeating sugarcane fields with a racemic mixture of 2-butanol ( rac-2B) released from polyethylene-tube dispensers on Miyako Island, Japan in 2011. An application of rac-2B released from 10,000 tube dispensers into 3,200 m sugarcane fields significantly reduced the mating rate of feral females and catches of feral males with R2B-baited traps compared with the results from untreated sugarcane fields. The larval density for the treated fields was found to be nearly zero in the following winter when the corresponding figure for untreated fields was high (1.73 and 2.33/40 × 40 cm quadrat). These results clearly show that the mating disruption technique using rac-2B could be highly promising for the control of D. ishigakiensis in sugarcane fields. [ABSTRACT FROM AUTHOR]

The use of magnetic resonance imaging (MRI) as a tool for in vivo detection of eggs in living Dasylepida ishigakiensis Niijima et Kinoshita, a major pest of sugarcane, was explored using females with an ovary at different developmental stages. MRI measurements of beetles were performed at 13 °C to avoid motion artifacts on the MR images. Spin-lattice relaxation time-weighted images allowed the observation of eggs at short acquisition times (2 min, 8 s). By comparing MR images with dissection data, criteria for determining mature eggs in MR images were a clear circular or ellipsoidal shape surrounded by a relatively bright rim and a size typically larger than 1.3 mm in the minor axis. Although small oocytes could not be detected, females with a developed or undeveloped ovary could be clearly distinguished based on MR images. The possibility of confusing the digestive tract as eggs in a female with a less developed ovary can be eliminated using a proton density weighted image. [ABSTRACT FROM AUTHOR]

The effects of changes in host plants on the mate-searching behavior and feeding preferences of the white-spotted longicorn beetle Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae) were examined. All individuals were raised on the same artificial diet until they became pupae. Analysis of the mate-searching behavior of the males showed that many more newly emerged males were attracted to the odor of the artificial diet than to an unbaited control. We prepared three groups of beetles and fed each group on different host plants for one week. The host plants used included the following: an artificial diet (containing Morus alba Linné), Citrus unshiu Marc. branches, and Vaccinium spp. branches. The mate-searching behavior of the males changed in relation to the plant supplied for feeding. Simultaneously, the preference among the three host plants was tested. The newly emerged males preferred the artificial diet. After a week of feeding on one of the three plants, however, the adult males selected and consumed significantly more of the plant that they had just experienced than the other plants. These results suggest that the male mate-location cue can be acquired after adult eclosion. In addition, the male beetles are capable of changing their host-plant preference. If they do so, they use different odor cues for mate location. Newly emerged A. malasiaca females showed no preference for their first choice of food among the three host plants presented, whereas the consumption was significantly larger on C. unshiu branches. After one week of feeding on different host plants, females chose their host plant after the adult stage as well as C. unshiu, but consumed mostly C. unshiu. These results suggest that the food preferences of females are different from those of males. The behavior of females may not be affected by chemical signals from their original host-plant species (as pupae) or from the host-plant species acquired when they emerge as adults. [ABSTRACT FROM AUTHOR]

Males of the white grub beetle, Dasylepida ishigakiensis Niijima et Kinoshita, transfer a large amount of a colloidal substance to females during mating. In this study we investigated the effect of the male substance on the reproductive performance of mated females and the significance of multiple mating of this beetle. Females artificially separated from the males 5 min after the start of mating produced fewer eggs than those separated after 30 min or those that were undisturbed and separated spontaneously, suggesting that the male substance is used as a nutrient for egg production by the females. When females were allowed to mate with 1-4 males, multiple mating had no clear effect on reproductive performance. The amount of male substance stored in the bursa copulatrix (BC) was not significantly increased by a second mating. The functions of multiple mating of this species may be to provide a chance for females to obtain sufficient amounts of male substance when the first male to mate has only small amounts of this substance, and to increase the genetic heterogeneity of the progeny. The presence of a serine proteinase and its possible involvement in the dynamics of the BC contents are reported. [ABSTRACT FROM AUTHOR]

Volatile chemicals from Citrus and Salix host plants evoke orientation behavior in males of the species Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae). These chemicals are emitted from wounded branches. We hypothesized that when released, these chemicals may indicate the presence of an individual to other conspecifics. Insects that originate from different host plants may use different plant chemicals from their own host to communicate with conspecifics. To further explore this theory, we investigated this communication system in a population of A. malasiaca from a third host plant, blueberry ( Vaccinium spp.). Males from a blueberry host ( Vaccinium population) were attracted to the odor of wounded Vaccinium branches when released near a female model in the laboratory, as has been observed in males found on Citrus and Salix host plants. The Vaccinium branch extract that was attractive to the males was separated into six fractions, of which two were active. Three active compounds were subsequently identified: β-caryophyllene and sulfur from the hexane fraction, and ( E)-phytol in the weakly polar fraction. The latter two active compounds of Vaccinium branches were different from those found in Citrus and Salix. [ABSTRACT FROM AUTHOR]

In 2010, abrupt outbreaks of the African armyworm, Spodoptera exempta (Walker), occured on the Tarama, Iriomote and Kikai Islands in southwestern Japan. Analysis by gas chromatography-electroantennographic detection (GC-EAD) revealed two EAG-active compounds on male antenna in crude extract of virgin females. These compounds were identified as (9 Z)-9-tetradecenyl acetate (Z9-14:Ac) and (9 Z,12 E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac) in ca. 90:10 ratio by subsequent GC-MS analyses. (11 Z)-11-Hexadecenyl acetate (Z11-16:Ac), which had previously been identified as a third component in the Kenyan population, was not detected. Binary blends of Z9-14:Ac and Z9E12-14:Ac at ratios between 99:1 and 90:10 showed a potent attractiveness in the field, superior to that of virgin females and comparable to that of the three-component formulation determined in Kenya. For the population survey, a 98:2 blend was used. In Tarama, only a few moths of S. exempta were captured with a light trap during the night when more than 600 males were captured with synthetic sex pheromone; more S. exempta captures with a light trap had been reported than with sex-pheromone traps in Kenya. This indicates that the Okinawan population has different properties from the Kenyan population in pheromone composition and behavioral response to light. [ABSTRACT FROM AUTHOR]

Genetic variation of the white-spotted longicorn beetle Anoplophora spp., distributed on the Japanese mainland and the Ryukyu Islands, was examined using nucleotide sequences of mitochondrial DNA. Two fragments, a 1.2-kb-long fragment containing portions of the cytochrome oxidase subunit I and II genes and a 1.4-kb-long fragment containing portions of 16S and 12S rDNAs, were sequenced. In phylogenetic analyses based on the sequences, 294 individuals collected at 75 localities were divided into two major groups (groups A and B) and then split into seven subgroups (A1-A4 and B1-B3). In group A, the closely related subgroups A1, A2, and A3 were mainly distributed on the Japanese mainland and were roughly separated among geographic areas, although the range of A3 spread significantly from Kyushu to the Central Ryukyu Islands. The sequence of A4, detected from one individual collected in eastern Honshu, was almost the same as that reported for A. chinensis (Forster) on the Chinese continent. In group B, subgroups B1 and B2 were restricted to the Central and Southern Ryukyu Islands, respectively, while B3 was distributed widely in both regions. Based on the results, we discuss the geographic origin of the haplotypes and movement of the insects between geographic areas. [ABSTRACT FROM AUTHOR]