Effect of humic substances on in vitro rooting and acclimatization of Alder (Alnus glutinosa (L.) Gaertn).

Humic substances (HS) are organic compounds resulting from the physical, chemical and microbiological transformations of organic residues. Present every where in the nature; they are taking part in basic functionalities in any ecosystems involving soils, sediments, waterand landfills. They are heterogeneous and complex carbon macromolecules. Our study aims to compare the effect of HS on in vitro rooting and acclimatization of the Alder species (Alnus glutinosa (L.) Gaertn) as tree growing on river banks or wasted areas.