African Journal of Agricultural Research Vol. 2(9), pp. 412-417, September, 2007

ISSN 1991- 637X­© 2007 Academic Journals

Full Length Research Paper

Bioecology of broad bean bruchid Bruchus rufimanus Boh. (Coleoptera : Bruchidae) in a  region of Kabylia in Algeria

F. Medjdoub-Bensaad^1, M. A. Khelil² and J. Huignard³

¹Laboratoire d’entomologie. Département de Biologie, Faculté des Sciences Biologiques et des Sciences Agronomiques. Université Mouloud Mammeri Tizi-Ouzou 15000, Algérie.

²Laboratoire de valorisation des actions de l’homme pour la protection de l’environnement et application en santé publique. Faculté des sciences  Université de Tlemcen 13000, Algérie

³Institut de Recherche sur la biologie de l’Insecte, Avenue Monge, 37200 Tours

*Corresponding author. E-mail: medjdoubferroudja@yahoo.fr

Tel: +213 71 94 72 91, fax: +213 21 68 19

Accepted 26 Aug, 2007

In this study, the conditions of colonisation of the broad bean Vicia faba L. by the adults of the Coleoptera Bruchidae Bruchus rufimanus Boh. were analysed in the region of Kabylia in Algeria. B. rufimanus adults began to colonise the V. faba cultures in February after termination of a larval and a reproductive diapause. Males appeared in February and had terminated their reproductive diapause. Females began to colonise the broad bean culture in March; they terminated their reproductive diapause after consumption of nectar and pollen of the host-plant flowers. The adult density depended on the abundance of the trophic resources at the beginning of adult colonisation phase. The females oviposited on the green pods as soon as they appeared on the plants and laid on these pods as long as they did not became mature. The first and the secondary larval instars developed in maturing seeds in the green pods. The last larval instars and the pupae developed in dry seeds after harvesting and storage in granaries. A high inter-individual variability in the duration of the post-embryonic development was observed in this study. The adaptive signification of this developmental heterogeneity was analysed in this study.

Key words: Vicia faba, Bruchus rufimanus, host plant colonisation, life cycle, larval and reproductive diapause, post-embryonic development.