Recovery of Verticillium dahliae from certified seed potatoes and characterization of strains by vegetative compability and aggressiveness

Potato (Solanum tuberosum L.) is a very important agricultural crop in Turkey and throughout the world. It is one of the four major vegetable sources such as wheat (Triticum spp), corn (Zea mays L.), rice (Oryza spp.) and is especially used for the food industry and many different fields. There are lots of factors that affect the production of potato crops; bacteria, fungi, viruses, mycoplasmas, viroids, and nematodes. Verticillium wilt is a very important disease of the potato (Solanum tuberosum L.) that is caused by the potato early dying by the soilborne fungus Verticillium dahliae. In this thesis, we worked on 110 Verticillium dahliae isolates, 63 of these VCGs have belonged to VCG4A, 24 are VCG4B, 19 are VCG2A and one isolate belonges to VCG2B that was applied pathogenicity test. In this study, we performed to the aggressiveness of V. dahliae, and to test the resistance of widely cultivated potato varieties against vegetative compatibility groups of V. dahliae.