Fungal metabolite extracts active against phytopathogens.
The effectiveness of some genetically engineered microorganisms in the control of plant disease pathogens is widely acknowledged. These biopesticides, so far, pose less danger to the environment. However, little attention has been paid to the potential benefit of the use of exometabolites of some microorganisms in spite of their known activity and high biodegradability. A total of 1108 fungal metabolite extracts obtained from different strains of micromycetes cultured in two different liquid media (malt extract and yeast saccharose) were tested for antifungal activity. The target organisms were Collectotrichum musae, Drechslera spicifera, Fusarium oxysporum, Geotrichum candidum, Pyricularia oryzae, Drechslera oryzae and Gerlachia oryzae. Percentage mycelial growth inhibition activities varied widely with the different taxonomic groups. Extracts from Aspergillus and Penicillium spp. consistently showed the highest activity. A greater number of micromycetes produced active extracts in a liquid yeast extract saccharose medium than in a liquid malt extract medium. Mycelial growth inhibition diameters were also greater in assays with extracts from the yeast extract saccharose medium. The results generally demonstrated fungal metabolite extracts as potential sources of agricultural chemical input.
Okeke
B
B
Laboratoire de Botanique, Université Joseph Fourier, Meylan, France.
Seigle-Murandi
F
F
Steiman
R
R
Buarque De Gusmão
N
N
D000898:Antibiosis; D005658:Fungi / Q000378:metabolism*; D010572:Pest Control, Biological; D010944:Plants / Q000382:microbiology*