COMPTES RENDUS DE L ACADEMIE BULGARE DES SCIENCES, vol.69, no.4, pp.539-548, 2016 (SCI-Expanded)
Lichens produce characteristic secondary metabolites, called lichen substances, which seldom occur in other organisms. Recent studies showed that they contain significant quantity of organic acid, amino acid, hormones and nutrients. The objectives of this study were to evaluate some chemical properties of ten lichen species (Dermatcarpon miniatum, Parmelia saxatilis, Ramalina farinacea, Letharia vulpine, Cladonia foliaceae, Hypogymnia physodes, Umbilicaria vellea, Usnea longissima, Cladonia rangiformis, Umbilicaria nylanderiana) for possible use as plant nutrient source in sustainable and organic agriculture. Current findings revealed that lichen species, especially Dermatcarpon miniatum, had quite high amino acid (histidine, alanine, cysteine, glutamate, aspartate, asparagine, glutamine, glycine), organic acid (butyric, propionic, malic, malonic, citric, maleic, and succinic acid) and hormone (gibberellic acid, salicylic acid, indole acetic acid and abscisic acid) contents. On the other hand, Dermatcarpon miniatum and Parmelia saxatilis lichen species had sufficient macro (N, P, K Ca, Mg and S) and micro (Fe, Cu, Mn, Zn and B) nutrient contents for cultivated plants throughout the growing season. It was concluded that the lichen species of Dermatcarpon miniatum, Parmelia saxatilis had significant potential to be used as an organic fertilizer source for plant growth in sustainable and organic farming.