Microbes are in almost all organisms on Earth. In humans, for example, scientists have presented evidence on the gut microbiome and its role in everything from behavior to health. Plants and trees also interact with a diverse microbial community in the soil that creates a working relationship for sustaining a healthy, functioning plant community.
Understanding the key functions of the microbiome plant world is what Associate Professor Michelle Afkhami studies in her biology lab at the University of Miami.
“An aspect of my research that has grown organically is understanding how microbes and plants are affected by climate change,” said Afkhami, who teaches courses on microbes, species interactions, ecology, and evolutionary biology in the College of Arts & Sciences.
“We also examine how microbes might be used to increase the resiliency of plant communities experiencing the effects of global change,” she adds. “For example, we look at how microbes in the leaves of mangroves mitigate effects like salinity changes due to sea-level rise and microbes in soils ameliorate stress from habitat fragmentation in plant communities due to urbanization.”
Afkhami’s research and knowledge of the microbial world earned her an invitation to write a thought-provoking, perspective article in the journal Science entitled, “Past microbial stress benefits tree resilience.” Her article is a commentary piece on a study that was simultaneously published in the journal by a team of scientists at the University of Wisconsin-Madison.
The researchers performed a microbe-inoculation project on tree seedlings grown in a greenhouse and then planted in forest areas around Wisconsin and Illinois. In essence, the study addresses how seedlings—or a new generation of trees—might have a chance to combat climate stressors (such as excessive cold or drought) if introduced to microbes that have previously encountered those stressors.
“Science is a great journal, and I was very excited to participate in this issue by writing the piece because it completely aligns with the research that I’m conducting in the lab,” said Afkhami. “It also gave me the chance to focus on a few emerging areas in the field, such as legacy effects, the longevity of microbiomes, and the possibility of multiple stressors interacting to disrupt the effects of microbiomes.”
According to Afkhami, the history (or legacy) of microbial soil can help predict the probability that the microbiome will ameliorate that climate change stressor. Experience with environmental stress means that the microbiome is better able to deal with that stress, and when it can deal with the stress, the microbes are able to fully function.
For example, if experiencing extreme drought conditions, the microbiome’s experience with drought could help it thrive in that environment and, in turn, benefit drought-stressed plant communities. But there could be major consequences moving microbes across different landscapes, she warns, such as displacing native plant and tree diversity in a way that is not beneficial to its growth and overall health.
“Ideally, we would need to figure out what a healthy, pristine plant community’s microbiome looks like, understand the functional role of the different microbes in the soil, and create an environment where that microbiome is thriving,” she said. “I’m an advocate for careful study of the microbiome when it comes to inoculation projects for tree restoration.”
“The interaction between microbiomes and plants is very important,” she adds, “and if we understand them well enough, we might be able to help improve the restoration of the plant community by understanding the hidden player in all of this.”
