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Sex ratio and female sexual status of the coconut pest, Oryctes monoceros (Coleoptera: Dynastidae), differ in feeding galleries and pheromone-baited traps

Published online by Cambridge University Press:  29 July 2008

K. Allou ,
J.-P. Morin ,
P. Kouassi ,
F. Hala N'klo  and
D. Rochat
K. Allou
Affiliation:
CNRA, Station Cocotier Marc Delorme, Laboratoire de Défense des cultures, 07 BP 13 Abidjan 07, Ivory Coast
J.-P. Morin*
Affiliation:
CIRAD-CP, UR 31, TA 80/02 Avenue Agropolis, F-34398 Montpellier Cedex 5, France
P. Kouassi
Affiliation:
Université de Cocody – Laboratoire de Zoologie et de Biologie Animale de l'UFR Biosciences - 22 BP 582 Abidjan 22, Ivory Coast
F. Hala N'klo
Affiliation:
CNRA, Station Cocotier Marc Delorme, Laboratoire de Défense des cultures, 07 BP 13 Abidjan 07, Ivory Coast
D. Rochat
Affiliation:
UMR1272, Physiologie de l'Insecte, Signalisation et Communication, INRA, R.D. 10, F-78026 Versailles cedex, France
*
*Author for correspondence Fax: +33-1.30.83.31.19 Email: [email protected]
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Abstract

Oryctes monoceros is a serious coconut pest, causing up to 40% damage in tropical Africa. Synthetic aggregation pheromone, ethyl 4-methyloctanoate, has been used to lure adults to traps. Traps with pheromone plus decaying palm material captured a high proportion of males. This raises the question whether individuals, which damage palms are receptive to the pheromone. We studied the sex ratio of the insects feeding on coconuts and those attracted to pheromone traps. Sixty two percent of adults from feeding galleries on living coconut palms were females. Pheromone with rotting palm material lured 43% females. To investigate the reasons for this difference, we compared the reproductive system of females lured to the odour traps or feeding in coconut galleries, or present in old rotting stems. Ninety six percent of the females trapped by pheromone had mated, and were sexually mature. In the galleries on living palms, 46% of females were immature, and 24% had not mated. In old rotting stems where eggs are laid and larvae develop, a mixture of 52% mated and 48% virgin females was found. Therefore, the pheromone together with the odour of rotting coconut stems signals a reproduction site to beetles, particularly mature females. In practice, the pheromone-baited traps will help in reducing the dissemination of gravid females, but will not affect directly the numbers of immature ones attacking palms. Our results show that when using pheromones for monitoring or controlling insects, the physiological status of the insects may have unexpected effects on the outcome.

Keywords

Oryctes monoceroscoconutpheromone trappingfemale reproductive systemsex ratio
Type
Research Paper
Information
Bulletin of Entomological Research , Volume 98 , Issue 6 , December 2008 , pp. 581 - 586
Copyright
Copyright © 2008 Cambridge University Press

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References

Allou, K., Morin, J.-P., Kouassi, P., Hala N'klo, F. & Rochat, D. (2006) Trapping of Oryctes monoceros (Coleoptera, Dynastidae) with synthetic pheromone and palm material in Ivory Coast. Journal of Chemical Ecology 32, 1743–1757.Google Scholar
Bedford, G.O. (1980) Biology, ecology and control of palm Rhinoceros beetle. Annual Review of Entomology 25, 309–339.Google Scholar
Gries, G., Gries, R., Perez, A.L., Oehlschlager, A.C., Gonzalez, L.M., Pierce, H.D. Jr,, Zebeyou, M. & Kouame, B. (1994) Aggregation Pheromone of the African Rhinoceros Beetles, Oryctes monoceros (Olivier) (Coleoptera: Scarabaeidae). Zeitschrift für Naturforschung 49C, 363–366.Google Scholar
Hinckley, A.D. (1973) Ecology of the Coconut Rhinoceros Beetle, Oryctes rhinoceros (L.) (Coleoptera: Dynastidae). Biotropica 5, 111–116.Google Scholar
Hurpin, B. & Fresneau, M. (1970) Etude en laboratoire du développement larvaire de Oryctes monoceros et O. rhinoceros. Annales de la Société Entomologique de France Hors Série 6, 193–214.Google Scholar
Lepesme, P. (1947) Les Insectes des Palmiers. 903 pp. Paris, Lechevalier.Google Scholar
Mariau, D. (1967) Les fluctuations des populations d'Oryctes en Côte d'Ivoire. Oléagineux 22, 451–454.Google Scholar
Mariau, D. (1968) Biologie du comportement alimentaire de l'Oryctes. Oléagineux 23, 377–380.Google Scholar
Morin, J.-P. (2002) New technology of pest management against insect pests of oil palm and coconut crops: Research on and development of selective trapping using synthetic attractants. INCO project ERB 18 CT 970199. Final report. Cirad Cp-sic N°1459. Montpellier, France, CIRAD-CP.Google Scholar
Morin, J.-P., Prawirosukarto, S., Purba, R., Beaudoin-Ollivier, L., Kakul, T., Aldana, R., Philippe, R., Dery, S., Desmier de Chenon, R. & Rochat, D. (2001) Protecting young oil palm and coconut plantings. A promising method: selective mass trapping of pest Coleoptera. International Conference on the future of perennial crops: Investment and sustainability in the humid tropics. pp. 95–96, November 5–9, 2001, Yamoussoukro, Ivory Coast.Google Scholar
Norman, K. & Basri, M.W. (2004) Factors affecting development of Oryctes rhinoceros in some substrates commonly found in the oil palm environment. Journal of Oil Palm Research 16, 64–77.Google Scholar
Prior, R.N.B., Morin, J.-P., Rochat, D., Beaudoin-Ollivier, L., Staters, T., Kakul, S. & Embuba, R.N. (2000) New aspects of the biology of the Melanesian Rhinoceros Beetle Scapanes australis (Col., Dynastidae) and evidence for field attraction to males. Journal of Applied Entomology 124, 41–50.Google Scholar
Rochat, D., Mohammadpoor, K., Malosse, C., Avand-Faghih, A., Lettere, M., Beauhaire, J., Morin, J.-P., Pézier, A., Renou, M. & Abdollahi, G.A. (2004) Male aggregation pheromone of date palm stalk borer Oryctes elegans. Journal of Chemical Ecology 30, 387–407.Google Scholar
Zelazny, B. & Alfiler, A.R. (1987) Ecological methods for adult populations of Oryctes rhinoceros (Coleoptera: Scarabaeidae). Ecological Entomology 12, 227–238.Google Scholar