UC Riverside

Maintaining efficient plant yields is critical to protect agricultural output levels that can support the global population. Unfortunately, crop yields can be devastated by drought conditions, pathogen attacks, and abnormal root growth due to stress. Recycled wastewater (RWW) can be employed to alleviate drought conditions, however, this source of water can deliver a set of chemicals referred to as chemicals of emerging concern (CECs). These compounds can have deleterious effects on the soil microbiome associated with the crop plants, thus reducing crop yields. Pathogens can be addressed with the application of fungicidal agents, but these often have off target effects that impact the soil microbiome. Plant growth promoting rhizobacteria (PGPR) can interact with plants through root development pathways and ensure that plant root development continues or is altered to cope with the stressful conditions. In our studies we examined how CECs and off target effects from fungicidal agents impact the soil microbiome associated with plants. We also examined how the PGPR Bradyrhizobium japonicum interacts with plants to facilitate root development. Overall the results suggest that CECs and off-target effects of fungicidal agents can impact the soil microbiome and alter their community functions. It was also observed that PGPRs were able to facilitate root development through auxin transport pathways.