Genetic diversity of fig accessions under atypical climatic conditions assessed by fruit quality and antioxidant activity

Abstract

During two consecutive years, we investigated main physical and chemical properties of 10 native fig accessions grown in situ under atypical i.e. moderate climate of Serbia. This study represents the first detailed research on the analysis of different types of fig accessions and evaluation of their main fruit quality attributes. Results showed that all evaluated traits significantly varied among accessions, whereas influence of year and interaction accession × year was minor. Fruit weight (FW) and fruit size were much higher in lighter accessions compared to dark colored ones. Three accessions (‘TMAF 5’, ‘TMAF 9’ and ‘TMAF 10’) had soluble solids content (SSC) higher than 20°Brix. ‘TMAF 8’ with brighter skin had the sweetest fruits compared to the rest. ‘TMAF 7’ accession with yellow-green skin had smaller values of SSC, pH juice, ripening index (RI) and ash and low to moderate titratable acidity (TA). This accession also had the lowest content of phenolic compounds. In contrast, dark skin fruits exhibited a higher total polyphenol content (TPC) compared to lighter fruits. The majority of significant correlation coefficients were found in the characteristics representing FW with fruit dimensions i.e. fruit size and fruit shape indexes. Also, strong correlations between the amounts of total phenolics, total flavonoids (TFC), antioxidant capacity (TAC), chlorophylls (a, b) and carotenoids were found. Principal component analysis (PCA) revealed that the first three components explained 82.20% of the total variation, where fruit physical and chemical traits contributed most of the total variation. Since the knowledge and experience about growing figs in Serbia is extremely modest, it is necessary to continue testing in the future.