The Dogwood Genome Project: A Model for Woody Ornamental Genomics

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

Dogwoods have long been cultivated for their showy flowers and fine-grained wood. Recently, the market value of dogwoods and related hydrangeas has increased as demand for woody ornamentals grows in the U.S. To advance the breeding potential of these economically and culturally important trees and shrubs, scientists can use genetics and advanced genomics to study critical agronomic traits such as flower characteristics, disease resistance and stress responses. New sequencing methods will be combined in this project to produce the first genome sequences for dogwoods and hydrangeas, allowing the research team to identify new markers and tools for breeding traits of interest. The team will study how some cultivars of flowering dogwood are resistant to damaging diseases such as powdery mildew. This information will be important to the nursery industry and will advance the broader understanding of how plant families have adapted and responded to diseases over time. The project will train students, teachers and breeders, and will reach out to the public by engaging citizen scientists to collect data on bud-break and flowering times for dogwoods in the U.S. This project will generate a high-­quality reference genome assembly and annotation for flowering dogwood (Cornus florida) cultivar Appalachian Spring. This resource, along with genome sequence and gene space assemblies for Asian kousa dogwood (C. kousa) and Hydrangea macrophylla, transcriptome atlases and high-density genetic markers, will provide a foundation for research and marker-assisted breeding for dogwoods, hydrangeas and other woody ornamentals. As members of the Cornales, dogwoods and hydrangea occupy a strategic position in the angiosperm phylogeny. Establishing sequences and analytical methods for the flowering dogwood genome will be an ideal catalyst for advancing comparative genomics across other angiosperm woody ornamentals, including members of the Asteraceae, Solanaceae and Convolvulaceae. In addition, the project will investigate the molecular basis of powdery mildew resistance through comparative analyses of mRNA and microRNA expression profiles in resistant and susceptible accessions of C. florida and C. kousa. All genome sequences and other data will be made available through the National Center of Biological Information (NCBI), the iPlant Collaborative http://www.iplantcollaborative.org and the Dryad Digital Repository http://datadryad.org.