Global climate change is projected to increase the spread of fungal infectious diseases due to persistent
stressful environmental conditions, such as record-breaking hot temperatures and droughts. Because
pathogenic fungi are good at tolerating stress, they may thrive under environmental stressful conditions
compared to other non-pathogenic fungi. The objective of this proposal is to investigate the relationship
between fungal pathogenicity and climate change. Specifically, if stress-tolerance brought by global climate
change triggers pathogenicity in soil fungi. The central hypothesis is that exposure to chronic environmental
stressors, such as heat and drought, favors the proliferation of pathogenic fungi in soil fungal communities and
enhances their stress-tolerance and pathogenicity. The rationale of this hypothesis is that upon completion of
this project, we will have identified mechanisms to better understand the relationship between climate change
and pathogenicity. Consequently, this will allow us to better plan for potential outbreaks of fungal infectious
diseases under global climate change, develop contingency plans, and potential treatments. The central
hypothesis will be tested by pursuing three specific aims: 1) Assess if stressful chronic conditions from climate
change, such as heat and drought, favor pathogenic fungi over non-pathogenic fungi in soils; 2) Determine if
heat and drought trigger saprotroph-to-pathogen transformations in fungi; 3) Evaluate if exposure to chronic
heat and drought cause persistent physiological changes in fungi including increased stress-tolerance and
pathogenicity. We will pursue these aims using an innovative and multi-scale approach which lies at the
intersection of microbiology, climate change, and public health. It includes the use of traditional microbiological
techniques coupled with recently developed high-throughput sequencing and bioinformatic tools. These will be
applied at the species and community level to assess short- and long-term responses. The proposed research
is significant because investigating how fungi are responding and adjusting to global climate change is vital for
understanding and predicting future fungal disease outbreaks. The expected outcome of this work is to obtain
comprehensive knowledge of the changes the soil fungal community undergoes when exposed to chronic heat
and drought. In addition, to better understand fungal resource investment under stressful environmental
conditions, including physiological responses underlying pathogenicity in wild fungal communities at multiple
scale. The results of this project will have a positive impact immediately because it will provide knowledge into
pathogenicity mechanisms that fungi undergo when exposed to stressful conditions. Therefore, my work will: 1)
provide foundational knowledge to model and predict future fungal disease outbreaks and 2) inform policy
makers on the public health threat potential that climate change has on soil fungal communities. Altogether,
fulfilling a long term-goal of my research program which is to help better plan to ensure the health of our
society under a changing climate.
