RT Journal Article SR Electronic T1 The bacterial community structure dynamics in Meloidogyne incognita infected roots and its role in worm-microbiome interactions JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.03.25.007294 DO 10.1101/2020.03.25.007294 A1 Timur Yergaliyev A1 Rivka Alexander-Shani A1 Hanna Dimeretz A1 Shimon Pivonia A1 David McK. Bird A1 Shimon Rachmilevitch A1 Amir Szitenberg YR 2020 UL http://biorxiv.org/content/early/2020/03/25/2020.03.25.007294.abstract AB Background Plant parasitic nematodes such as Meloidogyne incognita have a complex life cycle, occurring sequentially in various niches of the root and rhizosphere. They are known to form a range of interactions with bacteria and other microorganisms, that can affect their densities and virulence. High throughput sequencing can reveal these interactions in high temporal, and geographic resolutions, although thus far we have only scratched the surface. We have carried out a longitudinal sampling scheme, repeatedly collecting rhizosphere soil, roots, galls and second stage juveniles from 20 plants to provide a high resolution view of bacterial succession in these niches, using 16S rRNA metabarcoding.Results We find that a structured community develops in the root, in which gall communities diverge from root segments lacking a gall, and that this structure is maintained throughout the crop season. We detail the successional process leading toward this structure, which is driven by interactions with the nematode and later by an increase in bacteria often found in hypoxic and anaerobic environments. We show evidence that this structure may play a role in the nematode’s chemotaxis towards uninfected root segments. Finally, we describe the J2 epibiotic microenvironment as ecologically deterministic, in part, due to active bacterial attraction of second stage juveniles.Conclusions High density sampling, both temporally and across adjacent microniches, coupled with the power and relative low cost of metabarcoding, has provided us with a high resolution description of our study system. Such an approach can advance our understanding of holobiont ecology. Meloidogyne spp., with their relatively low genetic diversity, large geographic range and the simplified agricultural ecosystems they occupy, can serve as a model organism. Additionally, the perspective this approach provides could promote the efforts toward biological control efficacy.