Peach-nectarine is one of the widely cultivated cultivars in the world. As a result of breeding programs, new cultivars with different colors, textures, shapes, sizes , tastes have been developed. The cultivation of flat peach and nectarines from these cultivars has become important in recent years. The study was carried out between 2016-2018 to evaluate the performances of some flat peach and nectarine cultivars in Bursa ecology, which has an important position in the peach industry. In the study, Plane Ring, Plane Summer, Plane Gem, Plane Sun, Plane Delicious, Plane Silver, Plane Gold, Plane Super, Plane Star, Plane 222, Plane Top flat peach cultivars; Platerina 110 and Platerina 264 flat nectarine cultivars grafted on GF 677 rootstock were used. Phenological developmental stages, leaf curl prevalence rate and pomological characteristics of the cultivars were investigated. In the study Plane Ring and Plane Summer (June) cultivars were the earliest , Plane Top and Platerina 264 (August) were the last harvested. Leaf curl prevalence rate ranged from 25.0% (Plane Gold) to 76.7% (Platerina 264). Plane Sun gave higher values in fruit weight, fruit size and flesh/stone ratio, while Platerina 110 gave lower. Soluble solid content (SSC) of the cultivars were 13.3-18.1%; titratable acid content ranged between 0.20 , 0.68 (g 100ml-1); the ripening index varied from 23.0 to 82.2. When yield, fruit quality and disease prevalence were evaluated together in the study, Plane Silver cultivar came into prominence. In addition, although Plane Gold cultivar had lower yield, it gave positive results in terms of other quality criteria.
