Pomological and Biochemical Characterization of Autochthonous Grape Varieties Grown in Türkiye

Grapevine (Vitis vinifera L.) is an important fruit crop with considerable morphological and biochemical diversity, and autochthonous genotypes represent valuable genetic resources for breeding and conservation programs. Many local varieties remain underexplored in terms of pomological and antioxidant traits. Eighteen indigenous grape genotypes collected from Muş province (Eastern Anatolia, Türkiye) were evaluated using morphological and biochemical parameters, including berry traits, phenolic composition, vitamin C, and antioxidant activity. Multivariate analyses including PCA, HCA, and Pearson correlation were performed to classify genotypes and determine trait relationships. The first two PCA components explained 51.9% of the total variation. Antioxidant-related traits mainly contributed to PC1, whereas berry size and anthocyanin content influenced PC2. HCA grouped the genotypes into distinct clusters according to antioxidant capacity and pomological characteristics. Correlation analysis showed significant positive relationships among antioxidant-related parameters. Berry size traits were positively correlated with each other, but negatively associated with seed number and skin thickness. The combined use of pomological, biochemical, and multivariate analyses proved useful for genotype classification. The identification of antioxidant-rich genotypes may support future breeding and conservation studies. The results highlight the importance of indigenous grape germplasm for sustainable viticulture.