Definition and scope of forestry microbiology. Role of microorganisms in nature: eukaryotes and prokaryotes (1 hour). The eukaryotic cell (1). The eubacterial cell (4). Microbial metabolism: energetic (3) and biosynthetic (2). Bacterial growth. Nutrition of microorganisms. Autotrophy and heterotrophy (1). Genetics of bacteria (2). Classification of micro-organisms (1). Forestry and Environmental Microbiology. Microorganisms in the natural environment. Role of microorganisms in the genesis and evolution of forest land. Evolution of microorganisms in soil. Litter effect (2). Microbial biofilms (1). Environmental and forest microbiota: Actinomycetales , Bacteroidales , Cyanobacteria, (2), Bacillales , Clostridiales, (2), Rhizobiales, Pseudomonadales, (3), sulfur bacteria, nitrifying bacteria, iron-oxidizing bacteria, Cytophaga, Archaea (2). The carbon cycle: the degradation of cellulose, hemicellulose, lignin and other plant constituents (3). The nitrogen cycle: atmospheric nitrogen fixing bacteria, proteolytic, ammonifying, nitrifying and denitrifying bacteria (2). The sulfur cycle: sulfur mineralization, oxidation and reduction of mineral sulfur. The cycle of phosphorus, iron and manganese (1).