LWV25019 Tackling TSWV disease in Chrysanthemum (TS-02-227-043)

Chrysanthemum is one of the most important ornamental crops worldwide with most of the breeding companies concentrated in NW-Europe (mainly in the Netherlands, but also in Belgium and Germany). This region also hosts a significant number of commercial growers, making it an important area for chrysanthemum breeding and production. While considerable progress is being made in breeding for resistance to important fungal diseases like fusarium and white rust, viral diseases are becoming an increasing problem that remains difficult for breeding companies to tackle. Tomato spotted wilt virus (TSWV) is a prominent example, with a very wide host range. Although simultaneous and efficient virus detection methods are available, there is an urgent need for a reliable TSWV disease test that can be employed in a consistent bio-assay to screen for variation in susceptibility to TSWV, thereby paving the possibility to breed for TSWV-resistant pot, garden and cut-flower chrysanthemums. Next to the bio-assay, we aim to develop a screening method to identify potential specific resistances based on HR response triggered by variation in viral (coat) proteins, and to obtain a comprehensive overview of the diversity of chrysanthemum-infecting TSWV isolates across different production regions (both for cuttings and flowers). Depending on the outcomes of the bio-assay and effectoromics studies, a forward or reverse genetics approach will be employed to genetically characterize the TSWV disease resistance presence in chrysanthemum breeding material.