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bioRxiv · 10.1101/2020.03.11.988014

Testing the two-step model of plant root microbiome acquisition under multiple plant species and soil sources

Barajas, H. R.·Martinez-Sanchez, S.·Romero, M. F.·Hernandez-Alvarez, C.·Servin-Gonzalez, L.·Peimbert, M.·Cruz-Ortega, R.·Garcia-Oliva, F.·Alcaraz, L. D.
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Abstract

The two-step model for plant root microbiomes considers soil as the primary microbial source. Active selection of the plants bacterial inhabitants results in a biodiversity decrease towards roots. We collected in situ ruderal plant roots and their soils and used these soils as the main microbial input for single genotype tomatoes grown in a greenhouse. We massively sequenced the 16S rRNA and shotgun metagenomes of the soils, in situ plants, and tomato roots. Tomato roots did follow the two-step model, while ruderal plants did not. Ruderal plants and their soils are closer than tomato and its soil, based on protein comparisons. We calculated a metagenomic tomato root core of 51 bacterial genera and 2,762 proteins, which could be the basis for microbiome-oriented plant breeding programs. The tomato and ruderal metagenomic differences are probably due to plant domestication trade-offs, impacting plant-microbe interactions.

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Barajas, H. R., Martinez-Sanchez, S., Romero, M. F., Hernandez-Alvarez, C., Servin-Gonzalez, L., Peimbert, M., Cruz-Ortega, R., Garcia-Oliva, F., Alcaraz, L. D.. 2020-03-12. Testing the two-step model of plant root microbiome acquisition under multiple plant species and soil sources. https://doi.org/10.1101/2020.03.11.988014

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