Occurrence of Verticillium wilt on globe artichoke and screening artichoke genotypes for resistance to Verticillium dahliae in Turkey

Globe artichoke ( Cynara scolymus ) is an economically important plant that is cultivated in more than 30 countries. The main biotic constraint to globe artichoke cultivation is Verticillium wilt caused by Verticillium dahliae . In 2017, V . dahliae was found on globe artichoke in three locations (Manavgat-Cevizler, Kumluca-Hasyurt and Kumluca-Salur) of the Western Mediterranean Region of Turkey. V . dahliae was previously reported on globe artichoke in France, Chile, Greece, Italy, U.S.A., Spain and Tunisia. To our knowledge, this is the first report of V . dahliae causing Verticillium wilt on globe artichoke in Turkey. In addition, in the present study, three isolates of V . dahliae were characterized in vitro and in vivo . Pathogenicity, virulence and host specificity of the isolates were tested in five plant species. In the study, reactions of 18 globe artichoke genotypes to V . dahliae were also established by comparing disease severity (DS) of external and internal symptoms and AUDPC (area under disease progress curve). As a result, there was no significant ( P < 0.01) difference in virulence among the isolates. All three isolates of V . dahliae were pathogenic to globe artichoke, pepper and eggplant, whereas they were nonpathogenic to cucumber and tomato, indicating host specificity of the isolates. There were strong positive correlations (r= 0.93, 0.94 and 0.98) among DS of external and internal symptoms and AUDPC. Of globe artichoke genotypes tested, 10 and 4 were very susceptible and susceptible respectively, whereas 2 cultivars (Green globe and Romanesco) and 2 lines (M1 and M7) were moderately resistant to V . dahliae .