Effect of Fusarium, Paecilomyces and Trichoderma formulations against aphid Schizaphis graminum

Fungal strains belonging to the genera Fusarium Paecilomyces and Trichoderm a were tested in vitro in order to study their effects against Schizaphis g raminum one of the major pests of cereal crops around the world. Biological assays were performed using a solid formulation that was obtained from fun gal cultures grown on rice and then finely ground (less than or equal to0.2 mm). The occurrence of toxic secondary metabolites (fumonisin B-1 and beau vericin) produced by these fungi was also investigated. In each experiment, three groups of aphids: 15-hour old larvae, 5-day old nymphs with wing bud s and wingless morphs were treated with a suspension of a fungal formulatio n. Some strains belonging to the genera Fusarium and Trichoderma significan tly controlled the specimens of the three groups of S. graminum. The F. pro liferatum strain ITEM 1407, producing a high level of fumonisin B-1 in the culture (1250 mug/g), and F. larvarum strain ITEM 2139 had high insecticida l activity (> 60%) within 10 minutes after application. As F. larvarum ITEM 2139 did not produce metabolites toxic to mammals, it might be a good cand idate as a biocontrol agent of S. graminum in the field.