RESEARCH-PGR TRACK: Genetic basis of developmentally regulated heat stress response in rice

Plant reproduction is highly sensitive to environmental factors such as water and temperature. About seventy percent of human caloric needs are fulfilled directly or indirectly by grains/seed, which are a product of plant reproduction. Hence improving the environmental stress tolerance of staple crops (such as corn, wheat, rice, soybeans) during grain development is important for ensuring food sufficiency and nutritional value. This project will make genetic discoveries to enhance productivity and quality of rice grains during heat stress. The recent development of high-resolution imaging platform by this research team will lead to novel insights on how, when, and where plants respond to stress. Beyond genetic discoveries, this project will enable technological advancement in modeling and imaging techniques that have a broader impact on multiple scientific fields. Findings from rice will be applicable to other cereals such as wheat and corn because of how similar their grains develop. Outreach and training of K-12 students and high school teachers on combining biology with imaging technologies and data analysis will generate interest in science and technology thus advancing the nation’s goals of fostering a technology ready workforce. Even a transient heat stress occurring after fertilization can impact the grain size and quality in rice. Grain development on rice inflorescence (panicle) is asynchronous due to spatial variability in timing of fertilization. Heat stress differentially impacts the grains based on their spatial position. Using recent advancements in spatiotemporal imaging of rice panicles, this project will study the genetic basis of this spatial gradient under stress. Specifically, the project will test the hypothesis that the genetic variants that regulate this transient heat stress response in a developmental context along the panicle length contribute towards heat tolerance. A multidisciplinary research team will combine imaging, statistical modeling, quantitative genetics, and functional genomics for this research. This research will lead to the discovery of novel genes and pathways regulating the spatial variability in grain size and nutritional value. High school students will gain experience in using imaging to study plants through planned activities. Our outreach program for students and broader community will aim to increase awareness about impact of environment on nutritional quality of food. 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.