Löhr Bernhard, Kfir R..
2004. Diamondback moth Plutella xylostella (L.) in Africa. A review with emphasis on biological control.
In : Improving biocontrol of Plutella xylostella : Proceedings of the International Symposium, Montpellier, France, 21-24 October 2002. Kirk Alan A. (ed.), Bordat Dominique (ed.). CIRAD, USDA-ARS
Résumé : Past research on the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Africa is reviewed, including "gray literature" in the form of unpublished research reports of national research programmes and undergraduate research reports at universities in several countries: Benin, Ethiopia, Kenya, Malawi, Mozambique, Senegal, South Africa, Tanzania, Uganda and Zambia. Diamondback moth is ranked as the most destructive crucifer pest in all these countries yet yield loss information is not available. Research on P. xylostella control has concentrated on evaluation of pesticides and many of the older chemicals were rated ineffective. The use of botanicals and biological products has been studied in recent years and extracts from the Neem tree, the Syringa tree, a granulosis virus (P/xyGV) and Bt-based products were found effective in several countries. Forty four species of parasitoids associated with P. xylostella were listed in sub-Saharan Africa with great differences in species distribution. Highest parasitoid diversity was recorded in South Africa where parasitism rates often reach > 90%. It was suggested that in view of parasitoid diversity, DBM may originate in South Africa, where parasitoids appear to be able to maintain the pest below damage thresholds. Parasitoid abundance and effectiveness is much lower in other parts of Africa. In tropical West Africa, the most abundant parasitoid was Cotesia plutellae while Oomyzus sokolowskii was predominant in Sahelian countries. In large surveys in East Africa, parasitism rates were below 15% and the most frequent parasitoids were Diadegma mollipla and O. sokolowskii. Six attempts at classical biological control of P. xylostella are listed in Africa: South Africa in 1936 with the introduction of Diadegma semiclausum from England; Zambia in 1977 with introductions of C. plutellae and Diadromus. collaris; Cape Verde Islands in 1981-1982 with imports of C. plutellae and O. sokolowskii from Pakistan; Togo in 1991 with C. plutellae and D. semiclausum from Taiwan; St. Helena island in 1999-2000 with C. plutellae and D. collaris from South Africa, and in Kenya in 2001 with D. semiclausum from Taiwan. The African parasitoids D. mollipla, O. sokolowskii and four minor species were exported to Hawaii in 1953. Current efforts on biological control in East Africa are discussed and a strategy for biological control in Africa and elsewhere is developed.
Mots-clés Agrovoc : Plutella xylostella, lutte biologique, agent de lutte biologique, lutte chimique, pesticide d'origine végétale, parasitoïde, histoire, recherche, tendance
Mots-clés géographiques Agrovoc : Bénin, Éthiopie, Kenya, Malawi, Mozambique, Sénégal, Afrique du Sud, République-Unie de Tanzanie, Ouganda, Zambie
Classification Agris : H10 - Ravageurs des plantes
Auteurs et affiliations
- Löhr Bernhard, ICIPE (KEN)
- Kfir R., Plant Protection Research Institute (ZAF)
Autres liens de la publication
Source : Cirad - Agritrop (https://agritrop.cirad.fr/519637/)
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