title: The spatial distribution of acid phosphatase activity in ectomycorrhizal tissues depends on soil fertility and morphotype, and relates to host plant phosphorus uptake.
abstract: Acid phosphatase (ACP) enzymes are involved in the mobilization of soil phosphorus (P) and polyphosphate accumulated in the fungal tissues of ectomycorrhizal roots, thereby influencing the amounts of P that are stored in the fungus and transferred to the host plant. This study evaluated the effects of ectomycorrhizal morphotype and soil fertility on ACP activity in the extraradical mycelium (ACP(myc)), the mantle (ACP(mantle)) and the Hartig net region (ACP(Hartig)) of ectomycorrhizal Nothofagus obliqua seedlings. ACP activity was quantified in vivo using enzyme-labelled fluorescence-97 (ELF-97) substrate, confocal laser microscopy and digital image processing routines. There was a significant effect of ectomycorrhizal morphotype on ACP(myc), ACP(mantle) and ACP(Hartig), while soil fertility had a significant effect on ACP(myc) and ACP(Hartig). The relative contribution of the mantle and the Hartig net region to the ACP activity on the ectomycorrhizal root was significantly affected by ectomycorrhizal morphotype and soil fertility. A positive correlation between ACP(Hartig) and the shoot P concentration was found, providing evidence that ACP activity at the fungus:root interface is involved in P transfer from the fungus to the host. It is concluded that the spatial distribution of ACP in ectomycorrhizas varies as a function of soil fertility and colonizing fungus.
authors: Instituto de Ciencias de la Tierra y Evolución, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile. malvarez@uni-bremen.de
authors: Maricel
authors: M
authors: Alvarez
authors: Dries
authors: D
authors: Huygens
authors: Leila Milena
authors: LM
authors: Díaz
authors: Claudia Añazco
authors: CA
authors: Villanueva
authors: Wolfgang
authors: W
authors: Heyser
authors: Pascal
authors: P
authors: Boeckx
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism*; D001203:Ascomycota / Q000201:enzymology* / Q000502:physiology; D001487:Basidiomycota / Q000201:enzymology* / Q000502:physiology; D001692:Biological Transport; D016014:Linear Models; D019684:Magnoliopsida / Q000201:enzymology* / Q000382:microbiology / Q000502:physiology; D025282:Mycelium / Q000201:enzymology / Q000502:physiology; D038821:Mycorrhizae / Q000201:enzymology* / Q000502:physiology; D010758:Phosphorus / Q000378:metabolism*; D018517:Plant Roots / Q000201:enzymology / Q000382:microbiology / Q000502:physiology; D018520:Plant Shoots / Q000378:metabolism; D036226:Seedlings / Q000201:enzymology / Q000382:microbiology / Q000502:physiology; D012987:Soil / Q000737:chemistry; D013559:Symbiosis
chemical_list: D012987:Soil; D010758:Phosphorus; D000135:Acid Phosphatase