Adaptability of peach cultivars [Prunus persica (L.) Batsch] to the climatic conditions of the Ebro Valley, with special focus on fruit quality

Adaptability of 89 peach cultivars of distinct origin to climatic conditions of the Ebro Valley at the IRTA-Experimental Station of Lleida (Lleida, northern Spain) over three consecutive years (2009–2011) was studied. For this purpose, several agronomic, morphological and internal quality traits of the fruits were evaluated. Agronomic traits included bloom and harvest dates, yield, and yield efficiency, while morphological traits encompassed fruit shape and size, percentage of red skin, and an appearance quality index. The latter was established to facilitate the assessment of each cultivar on the basis of fruit appearance. Internal quality parameters included flesh firmness, soluble solids content, titratable acidity, sensory attributes, and relative antioxidant capacity. Under the climatic conditions of the Ebro Valley, extensive variability was observed for most quantitative and qualitative (breeding program, fruit type and flesh color) traits. In terms of agronomic performance and fruit quality (fruit appearance included), we considered that a well-adapted cultivar for a given area should achieve the following characteristics: high yield efficiency, high appearance index quality, high relative antioxidant capacity, strong flavor, and medium to high ripening index. However, according to the different breeding programs, fruit types, and flesh colors evaluated in this study, none of them simultaneously showed these characteristics. However, some achieved a number of the desired traits. A principal component analysis for melting peach, nectarine, non-melting peach and flat peach cultivars revealed the best ones for each fruit type. The results showed that cultivars do not combine all the desired traits. Nevertheless, these findings are valuable for breeding strategies aiming to achieve cultivars with better adaptation to the climatic conditions of the Ebro Valley.