Saprotrophic basidiomycete mycelia and their interspecific interactions affect the spatial distribution of extracellular enzymes in soil

• Published in: FEMS microbiology ecology 2011-10, Vol.78 (1), p.80-90
• Main Authors: Šnajdr, Jaroslav, Dobiášová, Petra, Vetrovský, Tomáš, Valášková, Vendula, Alawi, Alaa, Boddy, Lynne, Baldrian, Petr
• Format: Article
• Language: English
• Subjects: Abundance; alpha-Glucosidases - analysis; alpha-Glucosidases - metabolism; Bacteria; Bacteria - growth & development; Basidiomycetes; Basidiomycota - growth & development; Basidiomycota - metabolism; Basidiomycota - physiology; Biomass; Cellulose 1,4-beta-Cellobiosidase - analysis; Cellulose 1,4-beta-Cellobiosidase - metabolism; decomposition; Ecology; Enzymes; forest soil; fungal ecology; Fungi; Fungi - growth & development; Fungi - physiology; Hyphae - growth & development; Hypholoma fasciculare; microbial biomass; Microbiology; Mycelium - physiology; Nutrient release; Phanerochaete velutina; Soil - chemistry; Soil Microbiology; Soil surfaces; Soils; Spatial distribution; Xylosidases - analysis; Xylosidases - metabolism
• ISSN: 0168-6496; 1574-6941
• DOI: 10.1111/j.1574-6941.2011.01123.x

Abstract Saprotrophic cord-forming basidiomycetes are important decomposers of lignocellulosic substrates in soil. The production of extracellular hydrolytic enzymes was studied during the growth of two saprotrophic basidiomycetes,Hypholoma fasciculare andPhanerochaete velutina, across the surface of nonsterile soil microcosms, along with the effects of these basidiomycetes on fungi and bacteria within the soil. Higher activities of a-glucosidase, ß-glucosidase, cellobiohydrolase, ß-xylosidase, phosphomonoesterase and phosphodiesterase, but not of arylsulphatase, were recorded beneath the mycelia. Despite the fact thatH. fasciculare, with exploitative hyphal growth, produced much denser hyphal cover on the soil surface thanP. velutina, with explorative growth, both fungi produced similar amounts of extracellular enzymes. In the areas where the mycelia ofH. fasciculare andP. velutina interacted, the activities ofN-acetylglucosaminidase, a-glucosidase and phosphomonoesterase, the enzymes potentially involved in hyphal cell wall damage, and the utilization of compounds released from damaged hyphae of interacting fungi, were particularly increased. No significant differences in fungal biomass were observed between basidiomycete-colonized and noncolonized soil, but bacterial biomass was reduced in soil withH. fasciculare. The increases in the activities of ß-xylosidase, ß-glucosidase, phosphomonoesterase and cellobiohydrolase with increasing fungal : bacterial biomass ratio indicate the positive effects of fungal enzymes on nutrient release and bacterial abundance, which is reflected in the positive correlation of bacterial and fungal biomass content.