Genetic Diversity and Resistance Evaluation of Lithuanian Potato Varieties from the National Gene Bank

The research was conducted between 2014 and 2024 at the Vokė Branch of the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry. Experimental plots were established on sandy loam soil with carbonaceous fluvio-glacial gravel eluviated substrate (IDp), classified as Haplic Luvisols (LVh) according to the FAO-UNESCO system. The study involved a comprehensive evaluation of a potato (Solanum tuberosum L.) collection consisting of 287 varieties and hybrids originating from major potato-producing regions, as well as breeding material developed in Lithuania. The analysis revealed a high level of genetic diversity within the collection. Varieties exhibited significant variation in morphological, physiological, immunological, and agronomic traits, both within and across maturity groups. This genetic diversity has been directly applied in Lithuanian potato breeding programmes. Hybridisation methods were employed using the genetic resources preserved in the national collection, with the primary aim of developing disease-resistant varieties possessing superior agronomic performance and culinary quality. In addition, the study assessed the resistance of Lithuanian potato varieties to Phytophthora infestans (late blight) under diverse pathogen populations and climatic conditions in both Lithuania and Ukraine. The findings contribute valuable insights for the selection of resistant genotypes in the context of climate change and evolving pathogen pressures.