Increasing phosphorus removal in willow and poplar vegetation filters using arbuscular mycorrhizal fungi

Fast growing woody species are increasingly used in vegetation filters for wastewater treatment. Their efficiency in phosphorus (P) removal notably depends on plant uptake and storage in aboveground tissues. In this study, Populus NM5 (P. nigra × P. maximowiczii), Salix miyabeana (SX64) and Salix viminalis (5027) were planted in pots to evaluate the influence of colonization by arbuscular mycorrhizal fungi (AMF) Glomus intraradices on P uptake using two different P concentrations in irrigation water. Based on analysis of the foliar and woody components, our results show that the two treatments (inoculation with G. intaradices and P-irrigation) interact differently with total P content. Foliar P content is principally enhanced by the P-irrigation concentration, whereas the mycorrhizal colonization increases stem P content. In the presence of G. intraradices, both S. miyabeana and S. viminalis showed a 33% increase in stem P content. The latter finding is mainly due to an increase in biomass production, without modification of the P concentration, indicating that AMF associations affect P use efficiency. Thus, using arbuscular mycorrhizal fungi for phytoremediation strategies may increase biomass productivity and hence improve pollutant uptake.