Genetic variation in a radish (Raphanus sativus L.) geodiversity collection

Abstract A radish panel of 152 accessions with diverse root shapes was assembled from the National Plant Germplasm System (NPGS) collection based on weighted geographical sampling. Accessions represented 35 countries and were categorized into eight regions—North America, Europe, Africa, West Asia, Central South East Southeast Asia. Multiple plants per accession assayed using genotyping by sequencing (GBS), 8539 high-quality polymorphisms discovered. Average observed heterozygosity ( H o ) markers consistently ranged 5 to 7% in all regions. Asia most terms average expected e = 0.107), while least 0.050). Europe divergent each other (pairwise F ST 0.199), North America 0.022). The clustering genotypes principal components analysis (PCA) illustrated an east/west pattern. Large numbers private alleles a substantial proportion (3%) showing signals selection allele frequency differences indicate that allelic variation is available for cultivar development. European American gene pools could be expanded crossing Asian germplasm, vice-versa. Both potentially benefit sources, addition germplasm increase diversity. This resource molecular marker development combined understanding global genetic relationships will inform continued conservation improvement radish.