Effect of different nitrogen and carbon sources and concentrations on the mycelial growth of ectomycorrhizal fungi under in-vitro conditions

Abstract

Effect of different nitrogen and carbon sources and their concentrations in liquid media on the mycelial growth of six different ectomycorrhizal (ECM) fungal species was studied. Differences were found in the utilization of the different nitrogen and carbon sources between the fungal species. All the species showed better mycelial growth in the medium containing ammonium as nitrogen source. Growth was low in all species in medium in which nitrogen was supplied in nitrate form. All the ECM isolates investigated showed reduced growth in the medium containing maleic acid as the carbon source. The effect of glucose and di-ammonium hydrogen orthophosphate concentrations on mycelia growth of all the six fungal species was studied with ranges for glucose of 2–40 g/l, and for di-ammonium hydrogen orthophosphate of 2–20 g/l. Cortinarius fulvoconicus and Cortinarius flexipes showed maximal mycelial growth at a glucose concentration greater than 20 g/l. Suillus luteus, Scleroderma citrinum, Laccaria laccata, and Tricholoma aurantium showed maximal growth at a glucose concentration of 20 g/l. All six species showed maximal mycelial growth at 5–10 g/l of di-ammonium hydrogen orthophosphate concentration and with increased concentration mycelial growth in all species decreased.