Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Canada → Potential of Smicronyx spp. (Coleoptera:Curculionidae) as biological control agents of Striga hermonthica (Del) Benth and Alectra vogelii Benth (Scrophulariaceae) in Burkina Faso (West Africa)

McGill University Montreal (1997)

Potential of Smicronyx spp. (Coleoptera:Curculionidae) as biological control agents of Striga hermonthica (Del) Benth and Alectra vogelii Benth (Scrophulariaceae) in Burkina Faso (West Africa)

Otoidobiga, Lenli Claude

Titre : Potential of Smicronyx spp. (Coleoptera:Curculionidae) as biological control agents of Striga hermonthica (Del) Benth and Alectra vogelii Benth (Scrophulariaceae) in Burkina Faso (West Africa)

Auteur : Otoidobiga, Lenli Claude

Université de soutenance : McGill University Montreal, Quebec, Canada

Grade : Master of Science (MS) 1997

Résumé
The potential of Smicronyx umbrinus Hustache and Smicronyx guineanus Voss (Coleoptera : Curculionidae) as biocontrol agents of Striga hermonthica (Del) Benth was investigated at both population levels of Striga and Smicronyx spp. in the field in Burkina Faso. High population levels of Smicronyx spp. resulted in higher percentages of seed-pod galls although the weevils’ adult populations decreased during S. hermonthica seed capsule production. Smicronyx spp. were observed galling Striga aspera (Willd) Benth capsules ca. 60 days before S. hermonthica emerged in sorghum fields. The weevils also galled S. hermonthica stems at soil level and Sm. umbrinus was found to be the main species causing this symptom. Smicronyx spp. also galled Alectra vogelii Benth stems, Smicronyx dorsomaculatus Cox being the main species attacking this parasitic weed. Another Smicronyx species not yet described was collected on A. vogelii. Stem galls appeared to be more effective nutrient sinks than fruit galls. The weevils alone did not have sufficient impact to be considered successful biocontrol agents for S. hermonthica but they could contribute to an integrated control strategy against Striga. Smicronyx spp. have a good potential as biocontrol agents for A. vogelii.

Présentation

Version intégrale

Page publiée le 21 mars 2010, mise à jour le 1er décembre 2018