Les champignons entomopathogènes

Cissé Ousmane. 2001. Les champignons entomopathogènes. In : Les insectes ravageurs du sorgho en Afrique de l'Ouest et du Centre : actes = Insects pests of sorghum in West and Central Africa : proceedings. Ratnadass Alain (ed.), Ajayi Olupomi (ed.), Marley Paul S. (ed.), Akintayo Inussa (ed.). CIRAD, ROCARS, ICRISAT. Montpellier : CIRAD, 139-141. ISBN 2-87614-446-8 Atelier de formation sur les insectes ravageurs du sorgho, Samanko, Mali, 14 Octobre 1996/23 Octobre 1996.

Titre anglais : Insect pathogenic fungi

Résumé : More than 530 species of entomopathogenic fungi have been known, for more than a century for some of them. They are more abundant and diverse in the tropics than in other areas of the globe. The most important insect mycoses are myscardiniosis, cephalosporiosis, aspergillosis, and entomophtorosis. The first symptoms generally appear 4 days after the infection. Infection is either internal, through the guts, or by penetration through the external cuticle. In the latter case, first symptoms are gray or yellow stains on the body. Mycelium of the parasite invades the whole of the insect body, which gradually hardens, eventually resulting in the insect death. The mycelium develops then quickly, eventually forming white, ash-gray or green conidia, depending on the fungus species. The cases of Beauveria (=Botrytis) bassiana (Deuteromycetes, Botrytidae) and Metarrhizium (=Entomophtora) anisopliae (Siphomycetes, Entomophthorales) are taken as examples. Bio-pesticides based on entomopathogenic inocula include Boverine (a whitish powder containing 2-6 billion spores of B. bassiana per g), and Metarrhizium (a light green powder containing 1.5-3 billion spores of M. anisopliae per g), which cause respectively white and green myscardinioses in insects. The reasons which have hampered the use of entomopathogenic fungi as biological control agents are discussed.

Mots-clés Agrovoc : champignon entomopathogène, agent de lutte biologique, biopesticide

Classification Agris : H10 - Ravageurs des plantes

Auteurs et affiliations

• Cissé Ousmane, IER (MLI)

Source : Cirad - Agritrop (https://agritrop.cirad.fr/478743/)

Métriques

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