The drivers underlying biogeographical patterns of bacterial communities in soils under sugarcane cultivation

- There is biogeographical patterns at the bacterial community level.
- Soil characteristics explained much of the variation in the structuring of bacterial communities.
- Co-occurrence analysis indicates the importance of biological interactions.
- Members of Proteobacteria and Acidobacteria tended to co-occur.
- Results indicate that these bacterial assemblages are suitable for management.

The exploration of microbiomes has been posited as one of the pillars for innovative technologies to improve plant health and production. Agriculture is a promising area for this exploration as soils harbor vast and diverse microbial communities. A better understanding of the drivers influencing microbial biogeographical patterns is necessary to properly exploit this resource. Here, we aimed to describe biogeographical patterns of bacterial communities across a broad spatial scale by sampling soils in 10 distinct farms (a total of 285 soil samples) located at the most important region for sugarcane production in Brazil. Bacterial communities were analyzed in terms of community structure and composition and further correlated with soil characteristics, agricultural practices and geographical distances. Distance decay patterns were found either at the bacterial community level (as determined by T-RFLP and sequencing analyses) and at the distribution of most bacterial phyla. Partial redundancy analysis revealed that soil characteristics (i.e., pH, granulometry, potassium and phosphorus contents) and agricultural practices (i.e., amendments of vinasse, charcoal and mechanical harvesting) explained the differential structuring of bacterial communities to a higher extend than did geographical distance. The co-occurrence/mutual-exclusion analysis suggested a role of biological connections in these assemblages, such as the co-occurrence of Proteobacteria and Acidobacteria, both negatively correlated with Actinobacteria. Our data constitute the broadest assessment of biogeographical patterns of bacterial communities across agricultural soils. Collectively, it indicates that these bacterial assemblages are suitable for management, what support the development of microbiome-based strategies in agricultural settings.