Plant species within Streptanthoid Complex associate with distinct microbial communities that shift to be more similar and related under drought

Previous research has shown that drought can shift the rhizosphere microbial communities of related species such that the distinction is diminished. Still, how drought impacts the rhizosphere microbial communities of closely related species with differing affinity to serpentine soil remains to be explored. To explore this question, eight members of the Streptanthus clade with varying affinity to serpentine were grown in a lathhouse and subject to low, medium, and high watering regimes to simulate drought. DNA was extracted from rhizosphere soil and the 16S rRNA gene region was amplified and sequenced. DADA2 was used to identify and assign taxonomy to amplicon sequence variants (ASVs). Then analysis was used to determine the impact of watering treatment, species, and soil affinity on alpha diversity, differential abundances, beta diversity, and microbial features.