The Dynamic Assembly and Resilience of Panicum Root-associated Microbiota

University Of Texas At Austin, Austin TX

Investigators

Abstract

A series of pivotal scientific discovies over the past decade has shed light on the diversity of bacteria, termed the microbiome, that exist in the environment, particularly in soils. Plants cohabitate soil with these diverse bacterial communities, a subset of which are recruited to plant roots via a myriad of processes and can provide beneficial services to the host. For example, root associated bacteria can help the host plant acquire critical nutrients, thwart pathogen attack, and promote growth and yield. Therefore, there is widespread interest in harnessing the plant microbiome to increase yield and environmental resilience of agricultural commodities. A roadblock, however, is the complexity of the soil microbiome and the environment from which the host plants recruit root-associated bacteria. This makes dissection of the microbiome assembly process difficult under natural settings. A promising avenue to overcome this hurdle is by using controlled synthetic microbial communities, where previously isolated and characterized bacterial strains are inoculated into a controlled system. This research investigates the spatiotemporal dynamics of the switchgrass root microbiome by implementing synthetic microbial communities which are tractable, reproducible, and ecologically relevant. Switchgrass is native to the North America and is used as both a biofuel feedstock and in soil restoration. Previous efforts by the researchers undertook a comprehensive effort to cultivate members of the switchgrass microbiome across diverse locations. Here, the researchers will use these previously isolated bacterial strains to form reduced complexity communities to examine how bacteria assemble both across time and space on plant roots. This information will be used to form a network to infer microbe-microbe interactions which can be further tested by dropping out select microbial modules. These results will bring the field closer to fully understanding the root microbiome assembly process, will provide a resource in the form of a universal switchgrass synthetic microbiome which will be shared with other switchgrass / plant microbial ecologists, and may provide new avenues for beneficial microbe delivery into agronomic systems. 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.