The determination of reactions of some sunflower varieties and lines to downy mildew (Plasmopara halstedii (Farl.) Berl. & De Toni.) of sunflower

The aims of this thesis were that confirmation of resistance durability of PR64G46, Sanbro MR sunflower varieties and HA-460 line against the 703 and 710 races of downy mildew of sunflower compared to that of HA-89 line that was sensitive to all the downy mildew races of sunflower. This study was conducted under controlled conditions at Ege University. PR64G46, Sanbro MR sunflower varieties and HA-460 line sent by the Directorate of Seed Registration and Certification Center and Directorate of Trakya Agricultural Research Institute were used. After artificially inoculation tests, disease severities was calculated according to the scale, individually. HA-89 line was determined as sensitive to race of downy mildew of 703 and 710 with 47,57% and 51,06%, respectively. HA-460 line was calculated as high resistant to race of downy mildew of 703 with 73,06% while it was high resistant to race of downy mildew of 710 with 78,02%. PR64G46 variety was confirmed as high resistant to the races of downy mildew of 703 and 710 with 92,15% and 88,35%, respectively. Sanbro MR variety was also found as high resistant to the races of downy mildew of 703 and 710 with 98,04% and 92,15%, respectively.