Phenotypic Variation in Leaf Morphology of the USDA, ARS Sweetpotato (Ipomoea batatas) Germplasm Collection

Abstract

During 2012–14, 737 sweetpotato, Ipomoea batatas (L.) Lam. (Convolvulaceae), plant introduction (PI) accessions from the U.S. Department of Agriculture, Agricultural Research Service (USDA, ARS) sweetpotato germplasm collection were evaluated for several phenotypic leaf and plant characteristics, and a photographic record of each accession was made. Data were prepared for placement in the USDA, ARS Germplasm Resources Information Network (GRIN) database and the sweetpotato ontology. The parameters recorded for each genotype were canopy coverage, vine length, general leaf outline, leaf lobing, shape of the central leaf lobe, number of leaf points, leaf petiole length, leaf width, leaf length, leaf width × length, and leaf width/length (aspect ratio). The data indicate that there is wide genetic diversity for vegetative phenotypic characteristics within the USDA, ARS sweetpotato germplasm collection. This study provides important phenotype information for the USDA, ARS sweetpotato collection that has been lacking and can be used for curation of the collection and by researchers and breeders working with this important global food crop.