A study was carried out to determine the diversity of the microflora associated with the cereal cyst nematode, Heterodera avenae, in four cereal production regions of Algeria. The isolation was mainly targeted toward fungi associated to cyst nematodes. The isolation resulted in the identification of six fungi: Fusarium sp., Penicillium spp., Verticillium spp., Rhizomucor spp., Rhizopus spp.and Ulocladium spp. In all the prospected regions, Fusarium sp. is most frequently associated with cysts. The highest diversity is observed at Dahmouni with the genera Aspergillus spp., Ulocladium spp., Rhizopus spp. and Rhizomucor spp. The in vitro test showed that the metabolites of Fusarium spp., Penicillium spp.and Aspergillus spp. parasitize the eggs at a high rate and thus constitute potential agents for the control of H. avenae.

Keywords: Antagonists, fungi, bacteria, metabolites, cyst nematode, biological control