Abstract

SALA, Valéria Marino Rodrigues; FREITAS, Sueli dos Santos  and  SILVEIRA, Adriana Parada Dias da. Interaction between arbuscular mycorrhizal fungi and diazotrophic bacteria in wheat plants. Pesq. agropec. bras. [online]. 2007, vol.42, n.11, pp. 1593-1600. ISSN 0100-204X.  http://dx.doi.org/10.1590/S0100-204X2007001100011.

The aim of this work was to evaluate the inoculation effect of two new endophytic diazotrophic bacteria and the interaction between arbuscular mycorrhizal fungi (AMF) and these bacteria on wheat plants. The experiment was carried out in a greenhouse with the two strains of diazotrophic bacteria, IAC11HT (Achromobacter insolitus) and IAC12HT (Zoogloea ramigera), and two AMF (Glomus sp. and Acaulospora sp.). There was synergistic effect of the co-inoculation on root colonization by diazotrophic bacteria with the AMF of the genus Acaulospora. The plants colonized by Glomus associated to bacterial strains showed higher growth, accumulation and exploitation of the nutrients than plants colonized by Acaulospora sp., however, this effect did not surpass the treatments in which bacteria and fungi were inoculated separately. Although there were non-beneficial effects of the AMF-diazotrophic bacteria co-inoculation, for the most parameters assessed, these news bacteria strains promoted doubled shoot dry matter, shoot N and P concentration and accumulation in wheat plants.

Keywords : Zoogloea ramigera; Achromobacter insolitus; arbuscular mycorrhiza; nitrogen; phosphorus.