6533b7d8fe1ef96bd1269640

RESEARCH PRODUCT

Effect of Arbuscular Mycorrhiza establishment on the genetic structure and functionality of bacterial communities in the rhizosphere of Medicago truncatula

subject

description

Bacterial communities associated with (i) M. Truncatula J5 (Myc+/Nod+) and TRV48 (Myc+/Nod-), and with (ii) M. Truncatula TRV25 (Myc-/Nod-) were compared. The genetic structure of communities was characterized with an A-RISA DNA fingerprint. The genetic structures of communities associated with mycorrhizal and non-mycorrhizal roots were significantly different. Bacteria belonging to the Oxalobacteraceae and Comamonadaceae families were preferentially associated with mycorrhizal roots. The genetic diversity of cultured bacteria belonging to these groups was analysed by BOX-PCR. The diversity of isolates from mycorrhizal and non-mycorrhizal roots was significantly different. The functionality of communities was assessed by a proteomic approach. Proteins involved in structural stabilisation were more frequent in the metaproteome of communities associated with mycorrhizal roots suggesting bacteria colonising mycorrhizal roots might experience greater stress than those colonising non-mycorrhizal roots.