Current research interests 

I study nitrogen-fixing symbionts that associate with legume roots (a.k.a. rhizobia). Although microscopic, rhizobia play a major role in global nitrogen-cycles because both they and their plant hosts are so globally widespread. Rhizobia spend much of their time as free-living colonies in the soil so the goal of my DECRA is to understand how selective pressures from the soil environment impact how these symbiont associates with their hosts. For example, do more stressful soil environments lead to a stronger mutualistic relationship, or can it lead to a mutualism break down? How does the soil environment impact the dynamics of horizontally transferred genes, including genes that control symbiosis? I will be exploring these and other questions, moving towards the broader goal of understanding how we can leverage these mutualistic relationships for various applications, such as regenerative agriculture and habitat restoration in a changing climate.             

Challenges in my field 

Rhizobia, like all soil bacteria lead elusive lives in their natural and microscopic habitat. Because we cannot directly observe them, we have to use various indirect approaches, such as next generation sequencing, to gain a basic understanding of their ecology in the soil. The consequence of this approach is that, for each soil sample, we must shred the DNA of all organism into a fragmented, disorganized mess. Since a small soil sample can contain thousands to millions of species, a large part of my research will be implementing new bioinformatic approaches that enable us to infer the ecological and evolutionary dynamics of specific taxa, such as rhizobia. Overcoming these challenges will enable insight into how we can manipulate the soil microbe community and plant-microbe associations in complex soil environments.