tailieunhanh - Báo cáo lâm nghiệp: " Release of oxalate and protons by ectomycorrhizal fungi in response to P-deficiency and calcium carbonate in nutrient solution"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài: Release of oxalate and protons by ectomycorrhizal fungi in response to P-deficiency and calcium carbonate in nutrient solution. | Ann. For. Sci. 60 2003 815-821 815 INRA EDP Sciences 2004 DOI forest 2003076 Original article Release of oxalate and protons by ectomycorrhizal fungi in response to P-deficiency and calcium carbonate in nutrient solution Jean-Claude Arvieu Franck Leprince Claude Plassard UMR1222 INRA-ENSAM Rhizosphère et Symbiose 2 place Pierre Viala 34060 Montpellier Cedex 1 France Received 26 June 2002 accepted 10 October 2002 Abstract - The release of oxalate and H by six ectomycorrhizal isolates Hebeloma cylindrosporum 1 and 9 Paxillus involutus Suillus collinitus 2 and 22 Rhizopogon roseolus able to grow in vitro with NO- as the sole source of N was measured in response to orthophosphate Pi concentration 20 100 and 500 pM Pi and CaCO3 500 pM Pi in the solution. Without CaCO3 all isolates excepted H. cylindrosporum ones released oxalate. For each isolate oxalate production was not related to P-deficiency but was strongly enhanced by CaCO3. Whatever the medium composition H. cylindrosporum alkalinised the solution. Among oxalate-producing fungi S. collinitus 22 and R. roseolus exhibited an important proton efflux that could be related to transport phenomena for oxalate excretion. CaCO3 enhanced both oxalate and proton efflux increasing the chemical action exerted by the fungi on the mineral. oxalate production pH ectomycorrhizal fungi growth mineral nutrition Résumé - Liberation d oxalate et de protons par les champignons mycorhiziens en réponse à une carence en P et en carbonate de calcium dans la solution nutritive. La liberation d oxalate et de protons par six isolats fongiques ectomycorhiziens Hebeloma cylindrosporum 1 et 9 Paxillus involutus Suillus collinitus 2 et 22 Rhizopogon roseolus capables de se développer sur NO- comme seule source d azote a été mesurée en presence de differentes concentrations en orthophosphate Pi 20 100 et 500 pM et de CaCO3 500 pM de Pi dans le milieu de culture. En absence de CaCO3 tous les isolats libèrent de l oxalate excepté ceux de .