Abstract of Susan Stieve's proposed work, presented to the Department of Horticulture and Crop Science colloquium on 27 April 2011
Characterization of Rudbeckia Germplasm for use in the Ornamentals Industry
ABSTRACT: Rudbeckia (commonly called coneflower or black-eyed Susan) is a genus of 23 species of annual, biennial, and perennial plants indigenous to North America that are known for their colorful yellow ray flowers and prominent disk flowers. Several species are important crops in the floriculture and nursery industry and are valued for their ornamental characteristics and low maintenance requirements. The Ornamental Plant Germplasm Center (OPGC) at The Ohio State University conserves 180 accessions of Rudbeckia, consisting of 18 species from three sections. All accessions are freely available to researchers, including floriculture breeders, worldwide; the more information that is known about these accessions the more valuable they are to the researchers using them. The proposed research will focus on identifying botanical and horticultural characteristics important for germplasm assessment such as vegetative and reproductive morphology, ploidy, molecular “fingerprinting” (microsatellites), as well as tolerance to biotic and abiotic stresses. Based on these characteristics a Rudbeckia germplasm descriptor list will be developed and used to describe accessions conserved at the OPGC. Genotyping and ploidy information will be used to direct interspecific hybridization efforts as part of a germplasm enhancement program. Through interspecific crosses it may be possible to improve current cultivars by introducing traits desired by the ornamentals industry from other species. Results will facilitate germplasm management decisions for Rudbeckia including taxonomic identification of accessions, identification of genetic gaps and duplications within the collection, and may be useful in determining whether genetic drift occurs from one generation to the next during seed regeneration grow-outs. Results will be made available to researchers via the USDA/ARS National Plant Germplasm System’s Germplasm Resources Information Network (GRIN) website.