AbstractThe effect of cuticular waxes on the infection rate of pathogenic fungi. 1. Lophodermium pinastri and Botrytis cinerea. Spore germination and growth rate of germ‐hyphae ofLophodermium pinastriandBotrytis cinereaare influenced by low concentrations of cuticular waxes, added to the germination medium. The stimulating effect increases with decreasing resistance of the species or race used for wax sampling. Generally the separately tested alcohol‐, aldehyde‐, ester‐, fatty acid‐ and hydrocarbon fractions induce similiar but less pronounced reactions than total waxes. Exceptions occur. They led to suggestions in direction to single chemical components causing resistance. – Finally alcohol and hydrocarbon chromatOgrams of cuticular waxes forPinus montana, P. nigraandPicea abiesare presented for the