Downy mildew, caused by P. cubensis, is one of the most devastating diseases in cucumber (Cucumis sativus) worldwide. Due to the variation and mutation of the races of P. cubensis, host resistance in cucumber has been lost in recent years, so the identification of new sources of resistance is one of the most important targets in cucumber breeding programs. Moderate levels of resistance against downy mildew has been identified in different cucumber varieties. In this study, we identified new downy 2mildew resistance QTLs in cucumber using F2 mapping populations originated from the hybridization between breeding lines of cucumber. We used both classical QTL mapping based on SSR markers and GBS (gentyping based sequencing) based QTL mapping. In this presentation, detailed information about downy mildew resistance related QTL will be presented

• Sanghyeob Lee(Dept. of Bioresource engineering, Sejong University) Corresponding Author