CAREER:Contaminants of Emerging Concern in Treated Wastewater Impact Plant-Associated Microbes and Plant Stress Responses

The proposed study will investigate how chemicals of emerging concern (CECs) affect soybean associations with soil bacteria and consequently soybean yield. Soybeans are a major crop in the USA, generating more than $46 billion annual farm revenue. Soybeans are a popular rotation crop because they increase soil nitrogen through a mutualistic relationship with Bradyrhizobium, a genus of soil bacteria. Planting soybeans reduces chemical fertilizers application without compromising the yield of grain crops planted in rotation with soybeans. Understanding the effects of CECs on factors that directly impact yield, such as establishment of the soybean-Bradyrhizobium interaction, nodulation, and plant growth, will inform recycled wastewater quality decisions by water districts and growers in efforts to ensure sustainable agricultural productivity. The proposed research will also provide mentored research experience and training for students. The 10-week summer research module is designed to teach the students about plant-microbe interactions and provide them with lab experience needed in the workforce. One student will be recruited from this group to join the PI’s lab as paid student assistants and to help in training the next year's Summer Research Training students. Students and teachers from University Heights Middle School, in Riverside CA, will get hands-on training on the benefits of plant-microbe interactions and on how CECs can disrupt them. Despite overwhelming evidence that chemicals of emerging concern (CECs) alter microbial diversity, research regarding the impacts of CECs on plant-microbe interactions that are critical to plant health and productivity is lacking. For the first time, the proposed study will show the impacts of CECs on symbiotic interactions of great economic value using the soybean-Bradyrhizobium interaction. Using four CECs that are frequently found in southern Califormia the PI will investigate how CECs affect the soybean nodule, root and rhizosphere microbiome. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.