Improvement of Postharvest Quality of Asian Pear Fruits by Foliar Application of Boron and Calcium

The aim of this study was to evaluate the effects of foliar application of boron and calcium on postharvest storage characteristics of Asian pear (Pyrus pyrifolia) fruit. This experiment was carried out in the experimental orchard of Asian pear at Tarbiat Modares University, Tehran, Iran. The treatments were two concentrations of boric acid (0% and 0.5%) and three concentrations of calcium chloride (0%, 0.5%, and 0.7%) which were sprayed on trees during the growing season. The data showed that foliar application of these two elements resulted in improvement in physicochemical characteristics of the pear fruit, particularly fruit firmness and polyphenol oxidase activity. At harvest, fruit firmness and total soluble solids (TSS) were significantly improved by B and Ca application, compared to control fruit. Although fruit firmness decreased during 3 months of cold storage, fruit which received higher rates of Ca and B retained more firmness. During the storage period, total phenolic content was significantly reduced in control fruit compared to fruit which were sprayed with Ca and/or B. The highest level of polyphenol oxidase activity was in B and Ca sprayed fruit and the lowest was in control fruit. In general, foliar application of Ca and B resulted in improvement of postharvest characteristics of Asian pear fruit and reduced internal browning symptoms. Thus, application of Ca and B could be recommended as treatments for increasing postharvest life of Asian pear in similar semi-arid climates.