NSF Postdoctoral Fellowship in Biology FY 2019: The Genetic Architecture of Hydraulic and Whole-plant Performance Under Cold Temperatures in Sunflower

Stewart Jared J, Boulder CO

Investigators

Abstract

This action funds an NSF National Plant Genome Initiative Postdoctoral Research Fellowship in Biology for FY 2019. The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Dr. Jared J. Stewart is "The Genetic Architecture of Hydraulic and Whole-plant Performance Under Cold Temperature in Sunflower". The host institutions for the fellowship are USDA-ARS Water Management and Systems Research Unit (Fort Collins, CO), the University of Colorado-Boulder, and USDA-ARS Sunflower and Plant Biology Research Unit (Fargo, ND) and the sponsoring scientists are Drs. Sean M. Gleason, Nolan C. Kane, and Brent S. Hulke, respectively. Sunflower is one of the most widely produced oil crops across the globe. In the United States, many of the top sunflower-producing states experience episodic late-spring freezing temperatures. These freeze-thaw events pose a considerable threat to agricultural productivity through their dramatic impact on the water-transporting system of plants. This project aims to address this issue through identifying traits and genetics that confer superior performance under cold conditions in the common sunflower. Since this integrative project will occur at two USDA-ARS institutions with complementary missions as well as a public university, the results of this work should benefit ongoing efforts across multiple applied and fundamental disciplines. Furthermore, this experimental model could be adapted for other crops that are grown in locations with regularly occurring freeze-thaw events during the desired growing season. Training objectives for this project include characterizing hydraulic traits, identifying genetics underlying relevant traits, and developing high-throughput methods for efficient identification of superior crop lines. Broader impact activities during this project will include training and mentoring of undergraduate and graduate students as well as educational outreach at K-12 public schools and universities across northern Colorado. To meet agricultural demand in the face of climate change, plant functional traits and underlying genetics that allow superior plant performance under suboptimal environmental conditions must be identified. This project will contribute to this goal by characterizing the genetic architecture of hydraulic functioning in relation to high photosynthetic and whole-plant productivity under cold temperatures in sunflower. Relevant anatomical and functional traits will be characterized in plants grown under contrasting temperatures in climate-controlled growth chambers as well as plants grown in large-scale field trials. These results will be used to identify adaptive loci through both targeted and genome-wide association-mapping techniques. This project will feature over 300 accessions of the common sunflower, including the Sunflower Association Mapping (SAM) population, which encompasses 90% of the allelic diversity of cultivated sunflowers, as well as wild accessions that originate from a diversity of climates across its native range. Phenotypic and genotypic data from the wild accessions will be compared with climatic data from their respective sites of origin to provide ecological and evolutionary relevance, which could guide future breeding efforts for locations with exceptionally challenging climates. Phenotypic data from these investigations will be made available through the Sunflower Genome Database (https://www.sunflowergenome.org}, and genotypic data will be made available through the NCBI Short Read Archive database (https://www.ncbi.nlm.nih.gov/sra). Keywords: sunflower, hydraulic trait, abiotic stress, ecophysiology, association mapping, genomics, high throughput field-based phenotyping 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.