Efficacité fongicide de trois biopesticides à base d'huiles essentielles sur les principaux champignons associés aux semences de niébé au Burkina Faso.

Antifungal efficacy of three biopesticides namely Chirane, Lirane and Ocirane, formulated respectively from essentials oils of Cymbopogon schoenanthus, Lippia multifliora and Ocimum americanum, was tested on cowpea seedborne fungi. Blotting paper (ISTA, 1999) and Mathur and Kongsdal (2003) methods has been used respectively for seeds health analysis and effect of biopesticides on emergence of young plants and their development. Two doses of 5g/kg and 10g/kg were applied for each formulation, in the presence of a benchmark fungicide and an untreated control. Chirane reduced contamination by C. dematium and Fusarium spp. (25% and 4% respectively against 52 and 13% for the witnesses), Lirane led to a significant decrease in M. phaseolina infection (0% against 6%) and Ocirane, decreased contamination of Cladosporium sp., C. dematium, M. phaseolina and Fusarium spp. (7%, 29%, 0.5% and 1.5% respectively, against 57.5%, 40, 10 and 6.5% for the control). The antifungal effect of the biopesticides was lower than that of the benchmark fungicide. [ABSTRACT FROM AUTHOR]