%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Ranoarisoa, M. P.
%A Trap, Jean
%A Pablo, Anne-Laure
%A Dezette, D.
%A Plassard, C.
%T Micro-food web interactions involving bacteria, nematodes, and mycorrhiza enhance tree P nutrition in a high P-sorbing soil amended with phytate
%D 2020
%L fdi:010078924
%G ENG
%J Soil Biology and Biochemistry
%@ 0038-0717
%K Phosphorus cycling ; Microbial loop ; Bacillus subtilis ; Pinus pinaster ; Hebeloma cylindrosporum ; Rhabditis sp
%M ISI:000523634500011
%P 107728 [10 ]
%R 10.1016/j.soilbio.2020.107728
%U https://www.documentation.ird.fr/hor/fdi:010078924
%> https://www.documentation.ird.fr/intranet/publi/2020/04/010078924.pdf
%V 143
%W Horizon (IRD)
%X Phytate is considered a poorly available plant P source but proved to be useful for particular soil bacteria strains. In soil-free conditions, it has been shown that bacteria locked up the mineralized phosphorus from phytate whereas bacterial grazers like nematodes were able to deliver P to plants. Here, we aimed to determine if the interactions between phytate-mineralizing bacteria, bacterial grazer nematodes, and mycorrhizal fungi could increase plant P acquisition from phytate in high P-adsorbing soils. Pinus pinaster was grown in a Cambisol supplemented with phytate. Plants, whether associated or not associated with the ectomycorrhizal fungus Hebeloma cylindrosporum, were either inoculated or not inoculated with the phytase-releasing bacteria Bacillus subtilis and the bacterial-feeding nematode Rhabditis sp. After 100 days, the dual inoculation of bacteria and nematodes significantly increased net plant P accumulation. We observed that, on average, mycorrhizal plants accumulated more P in their shoots than non-mycorrhizal plants. However, the highest plant P acquisition efficiency was found when the three soil organisms were present in the P. pinaster rhizosphere. We conclude that, in a highly inorganic P-fixing soil, plant P acquisition from phytate strongly depends on the grazing of phytate-mineralizing bacteria. Our results confirm the importance of the soil microbial loop to improve plant P nutrition from phytate, which should be considered a route to improve the utilization of this source of poorly available P by plants.
%$ 068 ; 074 ; 076