ASHS 2025 Conference

With an economic value exceeding $68 billion USD, grapes are third in global horticultural crop production, with production across 93 countries. Recurring incidents of extreme weather conditions are forcing growers to alter conventional production practices. Reduced production areas, shifts in pest management, decreased water availability, increased temperature stress, and extreme weather events have all negatively impacted global grape production. There is a need to develop resilient grape cultivars that can survive the vagaries of nature. In the late 1800s, American horticulture scientist Thomas Volney Munson utilized 10 of the 13 Vitis spp. native to Texas and SW USA to develop cultivars that were adapted to the North American environment and resistant to the pests and pathogens of this area. Munson introduced 300 cultivars, of which 87 remain today. These cultivars have the potential to offer improved fruit quality combined with pest and pathogen resistance, traits that are sought after in modern grape breeding programs. Due to the wide range of parental material used to improve these native grapes, Munson’s cultivars offer a largely untapped genetic resource. By performing whole genome sequencing on the remaining 87 cultivars and the parental lines, we aim to develop a pangenome encompassing the full range of genetic diversity within the remaining Munson cultivars. This study will help clarify the lineage and shed light on any discrepancies in the records. The genomic characterization of the Munson cultivars will also aid in identifying potential resistance genes in these cultivars. This work is expected to secure profitable and resilient production of grapes in the US.