Genetic characterization of melon accessions in the U.S. National Plant Germplasm System and construction of a melon core collection

Abstract Melon ( C. melo L.) is an economically important vegetable crop cultivated worldwide. The melon collection in the U.S. National Plant Germplasm System (NPGS) a valuable resource to conserve natural genetic diversity and provide novel traits for breeding. Here we use genotyping-by-sequencing (GBS) technology characterize 2083 accessions NPGS collected from major production areas as well regions where primitive melons exist. Population structure analyses suggested that ssp. was firstly introduced centers of origin, Indian Pakistan, Central West Asia, then brought Europe Americas. East Asia likely derived agrestis India Pakistan displayed distinct background compared rest other geographic regions. We developed core 383 capturing more than 98% variation germplasm, providing publicly accessible future research genomics-assisted breeding melon. Thirty-five morphological characters investigated indicated high variability these across collection. Genome-wide association studies using panel identified potentially associated genome related fruit quality horticultural traits. This study provides insights into origin domestication, constructed loci with resources