Horizon 1 1 17 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES Pedobiologia 150685 [4 ] Arbuscular mycorrhizal fungi Rhizobia Dual inoculation Native strains Low-fertility tropical soil MADAGASCAR 2020 fdi:010080439 ENG Pedobiologia 0031-4056 ISI:000591875500003 https://www.documentation.ird.fr/hor/fdi:010080439 https://www.documentation.ird.fr/intranet/publi/2020/12/010080439.pdf 83 Horizon (IRD) The growth response of Phaseolus vulgaris to dual inoculation with arbuscular mycorrhizal (AM) fungi and rhizobia was studied in a low-fertility tropical soil in Madagascar. Two isolates of AM fungi identified as Acaulospora sp. and Glomus sp., respectively, along with a cocktail of ten Rhizobium spp. strains were used to conduct a greenhouse experiment in a fully randomized block design with two factors. The Phaseolus vulgaris seedlings received one of the following inoculation treatments: no inoculation, separate inoculation with each of the three microbial symbionts (the two AM fungal isolates and the rhizobia), and co-inoculation with each of the two AM fungal isolates and the mix of rhizobium strains. The results showed an additive effect of co-infection by AM fungi and rhizobia on plant growth and on the total N content of the plants, along with a synergistic effect on the total P content, the number of nodules and the mycorrhizal rate of the plants. Dual symbiosis with native strains contributes to the success of legumes, especially in harsh environments and low-fertility tropical soils. 084 ; 076 ; 068 UR210 / UR040 Madagascar