[Influence of lipids and fatty acids of egg yolk over growth and sporulation of Entomophthorales (author's transl)].

Proteic and lipidic fractions of the egg yolk were chemically isolated and used in solid synthetic media to study sporulation of 4 species of Entomophthorales. Neutral lipids are as good for growth and sporulation as polar lipids; the proteic fraction is only utilized as a nitrogen source. No specific factor of the sporulation was shown. The effect of fatty acids is studied: caproic, lauric, myristic, palmitic and oleic acids are the best for growth and sporulation. The results are discussed in view of considering the role of the lipids of the egg yolk and aphids on the physiology of Entomophthora.