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Sex pheromone of the African armyworm Spodoptera exempta (Lepidoptera: Noctuidae): identification of components of the Okinawan population and formulation for population monitoring

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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 (9Z)-9-tetradecenyl acetate (Z9-14:Ac) and (9Z,12E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac) in ca. 90:10 ratio by subsequent GC-MS analyses. (11Z)-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.

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  • Ando T (2010) Sex pheromones of moths (PDF file). Assessed 15 March 2011

  • Beevor PS, Hall DR, Lester R, Poppi RG, Read JS, Nesbitt BF (1975) Sex pheromones of the armyworm moth, Spodoptera exempta (Wlk.). Experientia 31:22–23

    Article  PubMed  CAS  Google Scholar 

  • Brown ES, Betts E, Rainey RC (1969) Seasonal changes in distribution of the African armyworm, Spodoptera exempta (Wlk.) (Lep., Noctuidae), with special reference to eastern Africa. Bull Entomol Res 58:661–728

    Article  Google Scholar 

  • Campion DG, Odiyo PO, Mushi AM, Hall DR, Lester R, Nesbitt BF (1976) Field tests with the synthetic sex pheromone of the African armyworm, Spodoptera exempta (Wlk). COPR Misc Rep 25:1–4 (cited in Cork et al. 1989)

  • Cork A, Murlis J, Megenasa T (1989) Identification and field testing of additional components of female sex pheromone of African armyworm, Spodoptera exempta (Lepidoptera: Noctuidae). J Chem Ecol 15:1349–1364

    Article  CAS  Google Scholar 

  • Haggis MJ (1986) Distribution of the African armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae), and the frequency of larval outbreaks in Africa and Arabia. Bull Entomol Res 76:151–170

    Article  Google Scholar 

  • Khasimuddin S (1978) Courtship and mating behaviour of the African armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae). Bull Entomol Res 68:195–202

    Article  Google Scholar 

  • Kováts E (1965) Gas chromatographic characterization of organic substances in the retention index system. Adv Chromatogr 1:229–247

    Google Scholar 

  • Oyama M (1972) Duration and frequency of mating of the tobacco cutworm moth, Spodoptera litura F. (Lepidoptera: Noctuidae), and trapping of the mating-ascertained males with the virgin females. Proc Assoc Pl Prot Shikoku 7:63–68 (in Japanese)

    Google Scholar 

  • Rose DJW, Dewhurst CF, Page WW (2000) The African armyworm handbook, the status, biology, ecology, epidemiology and management of Spodoptera exempta (Lepidoptera: Noctuidae), 2nd edn. Natural Resources Institute, Chatham, UK

    Google Scholar 

  • Struble DL, Arn H (1984) Combined gas chromatography and electroantennogram recording of insect olfactory Responses. In: Hummel HE, Miller TA (eds) Techniques in pheromone research. Springer, New York, pp 161–178

    Google Scholar 

  • Sugi H (1970) The Noctuidae of the Ryukyu Islands. Part I. Trifidae (Lepidoptera). Tinea 8:224–225 (in Japanese)

    Google Scholar 

  • Sugi H (1976) An example of Spodoptera exempta (Walker) (Lepidoptera, Noctuidae) found in Japan. Kontyû, Tokyo 44:385 (in Japanese)

    Google Scholar 

  • Sugi H (1982) Noctuidae. In: Inoue H et al (eds) Moth of Japan, vol 1. Kodansha, Tokyo, pp 669–913 (in Japanese)

  • Tucker MR (1984) Possible sources of outbreaks of the armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae), in East Africa at the beginning of the season. Bull Entomol Res 74:599–607

    Article  Google Scholar 

  • Uesato T, Zukeyama H, Shimatani M, Yamaguchi A, Kodama H, Tokashiki T, Wakamura S (2011) Outbreak of the African armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae), in Ryukyu Islands, Okinawa. Shokubutsu-boeki (Plant Protection) 65:365–370 (in Japanese)

  • Wakamura S (1988) Mating behavior of the beet armyworm moth, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae). Jpn J Appl Entomol Zool 33:31–33 (in Japanese with English summary)

    Article  Google Scholar 

  • Yoshimatsu S, Uesato T, Ibusuki H, Yuda T (2011) First recognition of the damage of crops by Spodoptera exempta (Walker) (Noctuidae) and the records of the adult moth until now in Japan. Jpn Heterocerists’ J 260:243–245 (in Japanese with English summary)

    Google Scholar 

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We thank Ayako Yamaguchi of the Miyako Substation of OPPPC and Naoki Haneji of the Tarama Village Office for cooperation in the collection of insects and operation of field experiments. Thanks are also due to Masahiro Taniguchi of Okinawa Prefectural Government, Keiji Yasuda of OPPPC for encouragement throughout the investigations and Serge Glushkoff for editing the manuscript.

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Correspondence to Sadao Wakamura.

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S. Wakamura, H. Yasui and M. Shimatani contributed equally to this article.

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Wakamura, S., Yasui, H., Shimatani, M. et al. Sex pheromone of the African armyworm Spodoptera exempta (Lepidoptera: Noctuidae): identification of components of the Okinawan population and formulation for population monitoring. Appl Entomol Zool 46, 415–420 (2011).

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