Preharvest factors affecting quality during 'Rocha' pear long-term storage

The present work focuses on studying the effect of preharvest treatments, such as different watering rates and nitrogen supplementation, on the postharvest physiology and quality of 'Rocha' pear. After harvest, pears were stored up to 5 months in refrigerated chambers with dynamic controlled atmosphere (DCA). Besides physical properties such as size, firmness and peel color, several key compounds were analyzed, for instance, acids, carbohydrate rates (glucose, sucrose, fructose and sorbitol), phenolics, antioxidants and a-farnesene. Physiological disorders such as superficial scald and internal browning, which can cause important economic losses to producers, were also assessed during this period of conservation. The treatments, excess irrigation and normal nitrogen or excess irrigation and excess nitrogen, showed a lower level of total phenolics and antioxidant activity, when compared with the control, after 3 or 5 months of storage. Additionally, a higher incidence of internal browning was observed in the same treatments. In normal irrigation and excess nitrogen, fruit showed an increase in fructose, with nutraceutical properties, and sorbitol, considered an osmoprotectant under abiotic stress. Therefore, although good storability and fruit quality can be ensured by DCA, an excess of water and/or nitrogen affects biochemical parameters, affecting the long-term storage capacity and nutritional value of 'Rocha' pears. These findings suggest the need for consolidated guidelines to manage the pre- and postharvest of this cultivar.