Selection of grape genetic resources of Vitis labrusca L. growing in the büyükliman basin of Trabzon

In this study, scented grape (Vitis labrusca L.) genotypes naturally growing in the districts of Trabzon called the Büyükliman basin (Beşikdüzü, Çarşıbaşı, Şalpazarı, Tonya and Vakfıkebir) were examined in a two-year study (2021-2022) and promising genotypes were determined as a result of pomological and chemical analyzes. According to the two-year data obtained from the study, it was determined that the fruit weights of the genotypes varied between 1.97 g (TB-17) and 4.11 g (TB-10). It was determined that the fruit width varied between 14.21 mm (TB-17) and 18.96 mm (TB-10), and the fruit length varied between 15.53 mm (TB-17) and 19.95 mm (TB-10). Cluster weight was observed between 31.95 g (TB-17) and 173.66 g (TŞ-5), cluster width was between 41.09 mm (TB-17) and 79.11 mm (TB-10), cluster length was between 88.42 mm (TB-16) and 178.12 mm (TŞ-5), cluster stem length was between 32.03 mm (TŞ-14) and 58.03 mm (TB-25). The number of seeds was 2 in both years and no difference was detected. It was recorded that pH values of the examined genotypes varied between 2.82 (TV-23) and 3.94 (TÇ-5), water soluble solids (WSS) amounts varied between 12.20% (TÇ-15) and 19.15% (TÇ-7) and titratable acidity (TAA) amounts varied between %0.57 (TV-21) and %1.72 (TB-22). Maturity index varied between 40.13 (TÇ-15) and 59.09 (TB-14), fruit shape index was 0.92 on average in both years and no difference was observed. Peel thickness varied between 0.20 mm (TÇ-14) and 0.38 mm (TB-17). As a result of biochemical analyses carried out on the genotypes of the Vitis labrusca species determined in the study; total antioxidant content varied between 17.10% (TŞ-1) and 76.35% (TT-3), total phenolic substance amount varied between 3.30 mg/g (TV-12) and 63.80 mg/g (TB-15), total monomeric anthocyanin content varied between 10.69 mg/L (TŞ-16) and 170.34 mg/L (TŞ-2), total protein amount varied between 5.20 mg/g (TB-24) and 9.57 mg/g (TT-4), polymeric color varied between 0.25 (TB-13) and 1.09 (TB-14), polymeric color intensity varied between 0.11 (TB-20) and 1.43 (TB-16) and polymeric color percentage varied between 28.72% (TB-20) and 295.87% (TB-16). As a result of the Modified Weighed Ranking method, the 13 genotypes with the highest scores (TB-11, TÇ-7, TT-3, TÇ-5, TÇ-10, TŞ-5, TV-8, TB-19, TÇ-15, TŞ-2, TŞ-3, TŞ-4 and TV-4) were determined as promising.