University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Carolina Escobar Rodriguez
(2021):
The Seed Microbiome – Ecology and relevance of bacterial seed endophytes of the model plant Setaria viridis L. for plant performance and development.
Doctoral Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 221.
UB BOKU
obvsg
- Abstract:
- Plants are associated with diverse microorganisms which contribute to plant growth by enabling nutrient acquisition and conferring resistances against stressors and disease. In contrast to the plant-microbe interactions of roots, the microbial ecology of disseminative organs remains comparatively unexplored. Seed microbial communities act as the initial inoculum for the emerging seedling with profound impacts on plant ecology, health, and productivity. In this work, the bacterial communities of the model plant Setaria viridis L. were investigated, with a special focus on the diversity, drivers, heritability, and functional importance of the bacteria within seeds. The methodology relied on a cultivation-independent approach, namely the metabarcoding of the bacterial 16S rRNA gene with subsequent Illumina sequencing. The soil environment with its microbial complexity was the main contributor in the bacterial communities within all plant compartments, including the developing seeds. Indeed, depleting the microbial complexity of the substrate resulted in seeds with reduced bacterial diversities that showed impaired germination rates and high mortality incidences of the emerging seedlings. Moreover, the bacterial communities of aerial plant compartments (e.g. stems and panicles) were highly variable compared to those in the root environment, reflecting the arbitrary nature of the alternative sources employed by the colonizers within these niches. In contrast to the soil environment, the contribution of the seeds in the bacterial communities of the adult plants was less evident. However, the seed microbiota may have a vital role in the assembly of early communities of seedlings laying the foundation to assemblages that ultimately establish within the adult plant. Members of the bacterial orders Burkholderiales, Rhizobiales, and Micrococcales were found consistently throughout this work, hinting towards an evolved form of mutualism with S. viridis.
- Betreuer:
- 1. Berater: