caa a22 4500 39755270X CHVBK 20180308164754.0 cr unu---uuuuu 161202e199603 xx s 000 0 eng 10.1111/j.1574-6941.1996.tb00210.x doi (NATIONALLICENCE)oxford-10.1111/j.1574-6941.1996.tb00210.x Dynamics of phosphorus translocation in intact ectomycorrhizal systems: non-destructive monitoring using a β-scanner [Elektronische Daten] [Sari Timonen, Roger D. Finlay, Stefan Olsson, Bengt Söderström] Phosphorus uptake and translocation through intact mycelial systems of Paxillus involutus and Suillus variegatus infecting Pinus contorta seedlings was monitored non-destructively using a β-scanner. Mycorrhizal plants were grown in flat perspex chambers (20 × 6 cm2) and root growth was restricted to the upper portion of each chamber enabling mycelial translocation to be studied over distances of up to 15 cm. 32P was supplied, either directly to distal parts of the extending mycelium, or to single, cut mycelial strands in feeding dishes. Two-dimensional patterns of activity were accumulated as scans with a lateral resolution of 5 mm and a longitudinal resolution of 3-4 mm. No distinct translocation front could be detected but patterns of accumulation of label in the mycorrhizal roots were not consistent with movement by simple diffusion. Activity in translocating hyphae became visible only after the activity in mycorrhizal root tips had been visible for a few days. In all cases there was a lag period of 20-50 hours before 32P could be detected in mycorrhizal root tips. Pre-feeding with unlabelled phosphate had no effect on this lag period. This implies continuous translocation of phosphate at low concentrations and a lag period due to the time needed for detectable levels of phosphate to accumulate in mycorrhizal roots. Thus the minimum velocity of phosphate movement in the hyphae would be 7.5 mm/h, if the first molecules of 32P arriving at the roots could be detected and the transport distance is 15 cm. Accumulation of phosphate to the roots was fairly constant, but not linear. The phosphorus uptake rate by intact mycelial margins was nearly four orders of magnitude higher than the uptake rate of cut mycorrhizal strands. The results indicate that the fine, foraging hyphae are better suited for nutrient uptake than mycelial strands and that phosphorus translocation in the hyphae occurs by active translocation of small amounts rather than by mass flow. © 1996 Federation of European Microbiological Societies. All rights reserved Ectomycorrhiza nationallicence Mycelium nationallicence Nutrient uptake nationallicence Phosphorus translocation nationallicence Pinus contorta nationallicence Timonen Sari Department of Biosciences, Division of General Microbiology, P.O. Box 56 (Viikinkaari 9), FIN-00014 University of Helsinki, Finland aut Finlay Roger D. Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut Olsson Stefan Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut Söderström Bengt Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut FEMS Microbiology Ecology Blackwell Publishing Ltd 19/3(1996-03), 171-180 19:3<171 1996 19 femsec https://doi.org/10.1111/j.1574-6941.1996.tb00210.x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1111/j.1574-6941.1996.tb00210.x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Timonen Sari Department of Biosciences, Division of General Microbiology, P.O. Box 56 (Viikinkaari 9), FIN-00014 University of Helsinki, Finland aut NATIONALLICENCE 700 1- Finlay Roger D. Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut NATIONALLICENCE 700 1- Olsson Stefan Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut NATIONALLICENCE 700 1- Söderström Bengt Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden aut NATIONALLICENCE 773 0- FEMS Microbiology Ecology Blackwell Publishing Ltd 19/3(1996-03), 171-180 19:3<171 1996 19 femsec Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford