Traubenwachstum und biochemische Eigenschaften der Tafeltraubensorte ‘Trakya Ilkeren’ (V. vinifera L.) nach Vorernte-Behandlungen mit verschiedenen Konzentrationen von Wasserstoffperoxid und Phenylalanin

Uneven grape ripening, leading to decreases economic valued of grapes is one of the main problems faced by grape growers in early table grape growing. In recent years, there has been increasing concern about improving of fruit quality in fruit crops. Among the various quality improvement methods, different types of foliar compounds are used for this purpose and hydrogen peroxide (H2O2) and phenylalanine (Phe) can be given as examples to some of these chemicals. This research was carried out during the 2015 growing season by using early ripening table grape cv. Trakya Ilkeren. In the study, it was assessed that how different doses of hydrogen peroxide (0, 10, 20 and 40mM) and phenylalanine (0, 1, 2 and 4mM) affected physical and biochemical properties of cv. Trakya Ilkeren. In terms of physical properties, doses of hydrogen peroxide and phenylalanine had only significant effects on grape firmness and cluster length. The best results were obtained from 4mM Phe application (6.76N) in grape firmness and were obtained from applications of 10, 20 and 40mM H2O2 (23.66, 23.86 and 23.99cm) and applications of 1, 2, and 4mM Phe (23.95, 24.46 and 24.88cm) in cluster length. However, most of biochemical properties were considerably affected by doses of hydrogen peroxide and phenylalanine except for juice pH and p-value. It was recorded that the highest total phenolic compounds contents varied from 3571.28 (10mM H2O2) to 3871.22mg GAE kg(-1) fw (40mM H2O2) compared to 0mM application (2591.48mg GAE kg(-1) fw). In terms of total anthocyanin content, the highest mean was recorded for 4mM Phe application (330.56mg GAE kg(-1) fw) than 0mM application (168.79mg GAE kg(-1) fw). As aresult, 4mM Phe application particularly improved the most of biochemical properties in cv. Trakya Ilkeren

Pflanzenentwicklung und bioaktive Substanzen bei der kernlosen Tafeltraubensorte ‘Recel Uzümü’ (V. vinifera L.) in Abhängigkeit von Dosierung und Zeitpunkt der Applikation von Thidiazuron

The purpose of this research was to appreciate the impact of the synthetic cytokinin, well known as thidiazuron (TDZ) on seedless berry quality of cv. 'Recel Uzumu'. Three concentration levels including 0, 5 and 10 mg/L were applied on the grapevines during different phenological stages of grapevine such as Time 1: beginning of berry stetting, Time 2: berries pepper corn size and Time 3: berries pea size. While TDZ application times had no impacts on cultivar characteristics, it was determined that the application doses of TDZ had major impacts on yield and quality components of cv. 'Recel Uzumu'. Consequently, ascending TDZ doses increased berry and cluster size and led to decreases in total soluble solids content, total phenolic compound content, total anthocyanin content and p-value of grape juice regardless of TDZ application time. The most effective TDZ dose was 10 ppm for improving berry and cluster size in cv. 'Recel Uzumu'