NSF Award
2217714
Plant interactions with soil microbes, including pathogens and mutualists, are critical for plant health, diversity, distribution, and abundance. Missing from much of this research is the link between evolutionary history and physiological mechanisms. This work explores the hypothesis that disease tolerance has been shaped in part by physiological adaptations to water, which balance fundamental tradeoffs between water retention and carbon acquisition. Because diseases like root rot limit access to water, physiological adaptations to water stress may be essential to understanding disease tolerance. Similarly, the presence of belowground mutualists may also mediate disease tolerance through physiological mechanisms. To explore these issues, the investigator will integrate physiological and microbial approaches across diverse Rhododendron taxa. Rhododendron provide an ideal system to conduct this research because of the variation among species in disease susceptibility to an invasive plant pathogen (Phytophthora cinnamomi). Phytophthora cinnamomi causes root rot disease and can infect over 5000 plant species. Understanding the mechanisms governing this interaction can improve selection for stress and disease tolerant crops. Characterizing the beneficial effects of mycorrhizal fungal mutualists also will enhance horticultural outcomes, including leading to healthier plants for the nursery industry. The project will give a mid-career scientist the opportunity to learn new physiological and microbiological tools to be applied to this and future projects. This work will enhance the PI’s career goals of developing a physiological and mechanistic program of study, deepening the understanding of plant-soil interactions, progressing toward promotion to Professor, and training a diverse lab in ecology and physiology. The PI and collaborators will provide training for diverse graduate and undergraduate researchers. Recruitment efforts will leverage existing programs such as the McNair Scholars and the North Star Consortium at Case Western Reserve University.<br/><br/>This investigator will conduct common garden and greenhouse experiments to explore the physiological and phylogenetic determinants of disease susceptibility. Growing 20 Rhododendron species across an experimental water gradient will provide a test of whether responses to water stress are shaped by evolutionary history. A greenhouse experiment will test how physiological mechanisms influence pathogen tolerance. Another experiment will explore how mycorrhizal mutualists modify physiological traits and disease susceptibility. This mid-career advancement award will also train the PI in cutting edge plant physiological techniques, including the measurement of turgor loss point, will train a graduate student in plant physiology and ecology, and will provide training opportunities for undergraduate researchers. This work will also include the development of an open access database, RA-LEAFY, to tap into the considerable community of enthusiastic Rhododendron and Azalea hobbyists and generate opportunities for scientific engagement for diverse students and community members. By providing an accessible entry point into scientific research, this work will enhance recruitment of diverse talent to the scientific workforce.<br/><br/>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.
