[Degradation of pine needles by Stereum hirsutum]

Pine-needle degradation by Stereum hirsutum was studied under conditions of solid state fermentation with the aim of accelerating its decomposition, avoiding the accumulation in situ and in view of the possible utilization of the residual organic matter. Three experimental systems were tested: pine needles alone and with the addition of either a nitrogen source or barley grain. Determinations were made at 14 and 28 days of incubation. All treatments showed substrate degradation. The addition of a nitrogen source raised enzymatic activities measured but not the degree of degradation. Grain addition resulted in higher biomass, enzyme activities, sugar accumulation and degradation of the substrate. Fungal biomass estimated as N-acetyl glucosamine allowed calculation of the actual degradation of the substrate, that reached 19% at 28 d of culture without additions and 44% at 14 d in pine-needles with grain.