Impact of Rootstock and Tree Position on the Biochemical Quality and Nutritional Stability of Pears During Storage

The nutritional value of fruit is essential for human health; however, these attributes may be lost or degraded during storage. Fruit behavior during the storage period is strongly influenced by pre-harvest production factors. In this study, biochemical quality parameters were analyzed post-harvest, as well as during and after storage in ultra-low oxygen (ULO) conditions. Three pear varieties ('Williams', 'Abate Fetel', and 'Conference') were evaluated on two rootstocks (quince and wild pear seedling) across three plot positions (top, middle, and base) over two consecutive years. The analyses included total phenolic content (TPC), antioxidant capacity (AOC), soluble solids content (SSC), and individual sugar profiles (glucose, fructose, sucrose, and sorbitol). The results indicate that the root-stock significantly influenced the analyzed fruit characteristics in cultivars investigated. Rootstock had a highly statistically significant impact on SSC of 'Abate Fetel' and 'Conference', whereas the difference was not significant for 'Williams'. All cultivars showed lower TPC and AOC on seedling rootstock. Conversely, the effect of tree position on the studied parameters and the stability of nutritional traits during storage was not statistically significant. It was concluded that the cultivars exhibited distinct behaviors under the storage regime depending on the factors observed. During storage, 'Williams' maintained a high nutritional value, particularly regarding phenolic and sugar content and strong antioxidant capacity. In contrast, 'Abate Fetel' and 'Conference' showed a decline in nutritional properties, which adversely affected overall fruit quality.