Plants grow and reproduce within a highly dynamic environment that can see abrupt changes in conditions such as light intensity, temperature, humidity, or the presence of different pathogens and insects. To achieve maximal yield, each leaf of the plant, and the plant as a whole, needs to rapidly adjust to these conditions, and the response of each of the different leaves within the same plant must be coordinated with each other. Such coordination is mediated by rapid signals that are transmitted between the different leaves and coordinate their individual responses, resulting in a synchronized overall response. This project aims to decipher the code used by plants to coordinate their response to different stresses, by studying how different leaves within the same plant send and receive signals to orchestrate the overall response of the plant. Unraveling these mechanisms would enable us to breed better plants with heightened tolerance to different environmental conditions. These could mitigate some of the multi-billion dollar losses to agricultural production, inflicted by environmental stresses, insects and pathogens, each year. The project provides training to 1 postdoctoral fellow, 2 graduate students, 16 undergraduates and 12 high school students including minorities. Outreach-based learning opportunities will be offered to thousands of K-12 students, as well as the general public, through programs such as Wheels of Science, Partnership for Research and Education, and the Elm Fork Education Center. In addition, educational videos focusing on the importance of science to our society will be developed and posted online.
Stress-induced systemic signaling and systemic acquired acclimation (SAA) play a key role in the acclimation of plants to different environmental conditions. To date, numerous studies have shown that in response to a particular abiotic stress applied to a single leaf (local tissue), plants mount a stress-specific SAA that includes the accumulation of many different stress-specific transcripts and metabolites, as well as more recently shown, a coordinated stress-specific canopy-wide stomatal response. In nature and under field conditions, however, plants are simultaneously subjected to a combination of different abiotic stresses that could have opposing effects on plant physiology, metabolism and acclimation, raising a new fundamental question in plant biology: How are different stress-specific systemic signals integrated in plants during stress combination? The overall hypothesis of this project is that different stress-specific systemic signals, generated at the same or different sites/tissues of the plant during stress combination, converge to induce a SAA response that is unique to the stress combination. Different omics tools in combination with computational methods, mutants, physiological measurements, acclimation studies and novel imaging techniques to detect systemic reactive oxygen species (ROS) waves in whole plants will be used to identify the site(s) and mode of integration of different stress-specific systemic signals in plants during stress combination. In addition, the different plant tissues involved in propagating systemic ROS signals during stress combination, transcriptional regulators and transcriptional networks, as well as plant hormones involved in the SAA response of plants to stress combination, will be identified and studied.
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.
