ORCC: Uniting long-term field experiments and modern genomics to prepare sustainable crops for the future

As climate warms globally, flowering time, animal migrations, insect emergence, and other harbingers of spring occur earlier on average than in centuries past. However, the genetic and environmental drivers behind these changes is not always clear, nor are the consequences of shifts in timing. Analyzing decades of sunflower field trials across dozens of sites, we will evaluate how particular plant genotypes grow, flower, and set seed under varying field conditions, and how the timing of their flowering interacts with environment to affect yield. We will then use detailed genomic information to characterize the specific genes underlying flowering time and performance under a diversity of climate conditions. This research will facilitate breeding for improved climate resilience critical for food security and for reducing environmental costs of agricultural production. Phenological shifts are the most well-documented organismal trait response to climate change. However, the genetic underpinnings of these changes and their adaptive significance are largely unknown outside of model systems. We aim to quantify the importance of phenology to plant performance in sunflower (Helianthus annuus L.) grown in diverse field environments including examining the plasticity in timing of flowering associated with key climate variables; identifying the genetic variation underlying flowering time and plasticity; and incorporating that information into sunflower breeding programs. Flowering timing (phenology) is regulated by a well-characterized network of genes that respond to known environmental and developmental signals in controlled conditions in sunflowers and other species. Our research builds on this foundational work to investigate the genetics of climate adaptation and translate functional genetic information into predictive models of plant performance under heterogeneous field conditions. Using yield, timing, genomic, and trait data for thousands of genotypes planted in dozens of field sites over 5 decades, we will evaluate hypotheses about how an entire network of genes affects phenology and fitness across broad spatial and temporal scales. 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.