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Azuki bean beetle, Callosobruchus chinensis (L.) (Coleoptera: Bruchidae), is a field-to-storage pest of legumes and its females produce sex pheromone components with two isomers: (2 Z ,6 E)-7-ethyl-3,11-dimethyl-2,6,10-dodecatrienal (2 Z -homofarnesal) and (2 E ,6 E)-7-ethyl-3,11-dimethyl-2,6,10-dodecatrienal (2 E -homofarnesal). Two-day-old virgin adults were treated with different doses (0, 200, 300, 400, 500, and 600 Gy) of gamma radiation and the effects on adult survivorship, fecundity, sterility, and pheromone production were studied. The longevity of both sexes and female fecundity were dose dependently affected by the gamma irradiation revealing that the fecundity was more reduced when the female adults were irradiated. Adults of both sexes were totally sterilized by the doses of gamma radiation tested in this study as depicted by the null hatchability of the laid eggs. The results from analyses by gas chromatography–mass spectrometry for solid phase micro-extraction revealed that both of the female sex pheromone components were significantly reduced by 300 Gy. Though significantly less, there was release of some amount of pheromone components by the irradiated female azuki bean beetles revealing the possibility of pheromonal attraction of males to the irradiated females. It is a pre-requisite for the successful sterile insect technology that the sterility of azuki bean beetle is induced without the total disruption of the calling behavior. [ABSTRACT FROM AUTHOR]

The winter cherry bug, Acanthocoris sordidus Thunberg (Hemiptera: Coreidae), widely spread in South Korea, Japan and Taiwan, is becoming an economic pest in these regions. Its elevated pest status in pepper plant, Capsicum annuum, is a trigger for eco-friendly management tactics. In order to use its pheromone for pest management, the cuticular components of adult A. sordidus were identified and a behavioral bioassay on the functions of the components was conducted. From the whole-body extracts of male and female A. sordidus, 13 compounds (hexanal, 1-hexanol, 2-hexanol, 3-hexanol, hexanoic acid, hexyl acetate, heptyl acetate, octyl acetate, tetradecane, 2-butyl-2-octenal, hexyl hexanoate and (2α,4α,6β)-2,4,6-tripentyl-1,3,5-trioxane (hexanal trimer, cis- and trans-forms) were identified. In addition to these, two unidentified compounds, a male-specific and a male-rich compound, were also found. Hexanal provoked clear escaping behavior. 1-Hexanol, hexyl acetate and hexanoic acid evoked weaker behavior than hexanal. We concluded that hexanal worked as an alarm pheromone and could be used as a pushing signal for a control program for A. sordidus. [ABSTRACT FROM AUTHOR]

BACKGROUND The spotted-wing drosophila ( SWD), Drosophila suzukii (Matsumura), is a globally invasive and serious pest of numerous soft-skinned fruit crops. Assessments were made of fumigant and contact toxicities of 12 Myrtaceae plant essential oils ( EOs) and their components. For determining the mode of action of major components of active EOs, their activities against acetylcholinesterase ( AChE) and Glutathione S-transferase ( GST) were also assessed. RESULTS Strong fumigant and contact toxicities were observed from EOs of Eucalyptus citriodora and Melaleuca teretifolia. The main components of E. citriodora were citronellal and isopulegol, whereas those of M. teretifolia were neral and geranial. Geranial showed the strongest fumigant activity, followed by citronellal or neral, M. teretifolia EO, isopulegol and E. citriodora EO. In contact toxicity assays, geranial also exhibited the strongest insecticidal activity, followed by neral or M. teretifolia EO, citronellol, citronellal, isopulegol and E. citriodora EO. Among the major components, all compounds showed low AChE inhibitory activity, while neral and geranial showed GST inhibitory activity against SWD. CONCLUSION Myrtaceae plant EOs and their components have an excellent potential for being used in the control of SWD adults and could be useful in the development of more effective natural compounds as alternatives to synthetic pesticides. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

ABSTRACT The bean bug, Riptortus pedestris is a major pest of bean pods and some tree fruits in north-east Asian countries. Scanning electron microscopy was conducted to investigate the morphology and distribution of antennal sensilla of R. pedestris to help in understanding the sensory mechanisms of the bug. Average antennal lengths of male and female R. pedestris were 11.00 mm and 9.84 mm, respectively, consisting of four distinct segments, scape, pedicel, basiflagellum, and distiflagellum. Based on the gross appearance, the antennal sensilla were classified into four major types (trichodea, basiconica, chaetica, and coeloconica), which could be further classified into four trichoid, three basiconic, four chaotic, and two coeloconic subtypes, based on their size, tip shape, presence of socket, and surface structure. Among them, two subtypes of trichoid sensilla, all three subtypes of basiconic sensilla, four subtypes of chaetic sensilla and two subtypes of coeloconic sensilla had numerous pores along the surface, suggesting their olfactory function. Nine subtypes (2 trichoid, 1 basiconic, 4 chaetic, and 2 coeloconic subtypes) showed a distinct socket structure at the base. Among the four antennal segments, the distiflagellum possessed highest number of sensilla. Trichoid sensilla were most abundant, followed by basiconic, chaetic, and coeloconic sensilla. Each subtype of sensilla exhibited distinct distribution profile along the four antennal segments. Two subtypes of trichoid sensilla, one subtype of basiconic sensilla and one subtype of chaetica sensilla were distributed on scape, pedicel, and basiflagellum, whereas distribution of other subtypes of sensilla was confined to basiflagellum and distiflagellum. Microsc. Res. Tech. 79:501-511, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

To develop an optimal attractant for M onochamus saltuarius ( Gebler) ( Coleoptera: Cerambycidae), the synergistic effects of a few potential attractants (ethanol and α-pinene as host-plant volatiles, and ipsenol and ipsdienol as bark beetle pheromones) were tested in a pine forest combined with 2-(1-undecyloxy)-1-ethanol (monochamol), the aggregation pheromone of M onochamus species, for two consecutive years, 2014 and 2015. Total number of catches was 65 and 33 in 2014 and 2015, respectively. Ethanol or ethanol + monochamol (a base blend) were not attractive to M . saltuarius with no difference from the control. Addition of α-pinene and ipsdienol to the base blend did not significantly increase catches. However, ipsenol was significantly synergistic to the base blend in attracting M . saltuarius in 2014, and the blend (ipsenol + base blend) attracted meaningfully higher numbers of M . saltuarius in 2015. Our study illustrates the potential for monochamol and ipsenol baits for monitoring and trapping of M . saltuarius in the field. [ABSTRACT FROM AUTHOR]