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.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.20276 |
| Date | January 1997 |
| Creators | Otoidobiga, Lenli Claude. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Natural Resource Sciences.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001608901, proquestno: MQ44238, Theses scanned by UMI/ProQuest. |
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