TECHNIQUES FOR CONTROLLED SYNTHESIS OF THE DOUGLAS-FIR - LACCARIA-LACCATA ECTOMYCORRHIZAL SYMBIOSIS

Laccaria laccata (Scop ex Fr) Cke is an ectomycorrhizal basidiomycete which is very efficient for the controlled mycorrhization of Douglas-fir (Pseudotsuga taxifolia Poir Britt). Studying the biology of this symbiosis led to the development of a number of experimental techniques for aseptic and non-aseptic synthesis. This paper describes seed treatments, fungal inoculum preparation, substrates, nutrient solutions, aseptic experimental systems (test tubes and Petri dishes) and non-aseptic systems (pot experiments in the glasshouse) and bare-root nursery techniques. The specificity of each technique is discussed according to the experimental purpose.