The RemainGrape project investigates endangered traditional grapevine cultivars (Vitis vinifera L.) and wild grapevine populations (Vitis vinifera L. subsp. sylvestris Hegi Gmelin) in Croatia.

It applies an interdisciplinary approach to evaluating grapevine genetic resources, combining phenotypic and genomic methods based on next-generation DNA sequencing. The project involves collaboration with local biodiversity experts and field specialists to identify remaining hidden cultivars and sylvestris populations in the field.

Sampling will be conducted in the remaining old vineyards located at historical viticultural sites, particularly in the Adriatic region and a smaller part of continental Croatia. The phenotypic characteristics of collected samples will be analyzed using standard grapevine descriptors and high-throughput methods, while genetic diversity will be assessed using microsatellite markers and a targeted sequencing system based on the Single Primer Enrichment Technology (SPET) panel, which includes 50,000 probes covering gene space of the Vitis vinifera L. genome. The obtained data will be integrated with historical ampelographic literature and the international Vitis species database (Vitis International Variety Catalogue).

The RemainGrape project will contribute to the conservation of global grapevine genetic diversity and sylvestris populations, helping to protect endangered cultivars that are missing from the grapevine biodiversity mosaic. Additionally, it will enhance understanding of the genetic structure of Croatian grapevine cultivars and sylvestris, providing insights into the presence of resilience genes that may be beneficial for climate change adaptation and sustainable viticulture.