Phenotypic analysis of fruit quality traits and effect of climate in an apple (Malus × domestica Borkh) germplasm bank of Aragón, Spain

Apples are among the most widely consumed fresh fruits in the world. They are appreciated in terms of flavor, nutritional and health-promoting compounds. molecules are associated with a reduced risk to develop diseases. In this , a total of 155 accessions of Malus × domestica Borkh from an apple Germplasm established at the Experimental Station of Aula Dei, located in the Ebro Valley (Northeastern Spain, Zaragoza) were studied. Basic fruit quality traits as soluble solids (SSC), titratable acidity (TA) and the ratio SSC/TA (ripening index – RI), were . Biochemical traits as total phenolics content (TPC), flavonoids, vitamin C and antioxidant capacity (RAC) were also determined for five consecutive years. R software, an ANOVA analysis, Pearson’s correlations and a principal analysis (PCA) were constructed. In addition, a mixed-effects model was . Trait values differed significantly among accessions and years. Each trait was used as dependent variable in the model (only TPC is discussed), the features as independent variables or fixed effects, and the variety as random . Using the Akaike Information Criterion (AIC) statistic, the best significant model selected. It included precipitation (although non-significant), minimum daily and solar radiation. The R2 of the model was 0.85, and the mean absolute (MAE) was 5.75. A cluster analysis was performed on the model coefficients space classify the 155 accessions, using the Ward’s D method based on the Euclidean . A solution with 5 groups was selected as optimum. The foreign accessions concentrated in two groups. In general, the bioactive compounds values tended to with highest temperatures meanwhile to increase with higher solar radiation. analyses highlighted accessions and climate as main factors affecting profile and fruit characteristics.